| 1 | <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
|
|---|
| 2 | "http://www.w3.org/TR/html4/loose.dtd">
|
|---|
| 3 | <html >
|
|---|
| 4 | <head><title>Vorbis I specification</title>
|
|---|
| 5 | <meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
|
|---|
| 6 | <meta name="generator" content="TeX4ht (http://www.tug.org/tex4ht/)">
|
|---|
| 7 | <meta name="originator" content="TeX4ht (http://www.tug.org/tex4ht/)">
|
|---|
| 8 | <!-- html -->
|
|---|
| 9 | <meta name="src" content="Vorbis_I_spec.tex">
|
|---|
| 10 | <link rel="stylesheet" type="text/css" href="Vorbis_I_spec.css">
|
|---|
| 11 | </head><body
|
|---|
| 12 | >
|
|---|
| 13 | <div class="maketitle">
|
|---|
| 14 |
|
|---|
| 15 |
|
|---|
| 16 |
|
|---|
| 17 |
|
|---|
| 18 | <h2 class="titleHead">Vorbis I specification</h2>
|
|---|
| 19 | <div class="author" ><span
|
|---|
| 20 | class="cmr-17">Xiph.Org Foundation</span></div><br />
|
|---|
| 21 | <div class="date" ><span
|
|---|
| 22 | class="cmr-17">July 4, 2020</span></div>
|
|---|
| 23 | </div>
|
|---|
| 24 | <h3 class="likesectionHead"><a
|
|---|
| 25 | id="x1-1000"></a>Contents</h3>
|
|---|
| 26 | <div class="tableofcontents">
|
|---|
| 27 |  <span class="sectionToc" >1 <a
|
|---|
| 28 | href="#x1-20001" id="QQ2-1-2">Introduction and Description</a></span>
|
|---|
| 29 | <br />  <span class="subsectionToc" >1.1 <a
|
|---|
| 30 | href="#x1-30001.1" id="QQ2-1-3">Overview</a></span>
|
|---|
| 31 | <br />   <span class="subsubsectionToc" >1.1.1 <a
|
|---|
| 32 | href="#x1-40001.1.1" id="QQ2-1-4">Application</a></span>
|
|---|
| 33 | <br />   <span class="subsubsectionToc" >1.1.2 <a
|
|---|
| 34 | href="#x1-50001.1.2" id="QQ2-1-5">Classification</a></span>
|
|---|
| 35 | <br />   <span class="subsubsectionToc" >1.1.3 <a
|
|---|
| 36 | href="#x1-60001.1.3" id="QQ2-1-6">Assumptions</a></span>
|
|---|
| 37 | <br />   <span class="subsubsectionToc" >1.1.4 <a
|
|---|
| 38 | href="#x1-70001.1.4" id="QQ2-1-7">Codec Setup and Probability Model</a></span>
|
|---|
| 39 | <br />   <span class="subsubsectionToc" >1.1.5 <a
|
|---|
| 40 | href="#x1-90001.1.5" id="QQ2-1-9">Format Specification</a></span>
|
|---|
| 41 | <br />   <span class="subsubsectionToc" >1.1.6 <a
|
|---|
| 42 | href="#x1-100001.1.6" id="QQ2-1-10">Hardware Profile</a></span>
|
|---|
| 43 | <br />  <span class="subsectionToc" >1.2 <a
|
|---|
| 44 | href="#x1-110001.2" id="QQ2-1-11">Decoder Configuration</a></span>
|
|---|
| 45 | <br />   <span class="subsubsectionToc" >1.2.1 <a
|
|---|
| 46 | href="#x1-120001.2.1" id="QQ2-1-13">Global Config</a></span>
|
|---|
| 47 | <br />   <span class="subsubsectionToc" >1.2.2 <a
|
|---|
| 48 | href="#x1-130001.2.2" id="QQ2-1-14">Mode</a></span>
|
|---|
| 49 | <br />   <span class="subsubsectionToc" >1.2.3 <a
|
|---|
| 50 | href="#x1-140001.2.3" id="QQ2-1-15">Mapping</a></span>
|
|---|
| 51 |
|
|---|
| 52 |
|
|---|
| 53 |
|
|---|
| 54 | <br />   <span class="subsubsectionToc" >1.2.4 <a
|
|---|
| 55 | href="#x1-150001.2.4" id="QQ2-1-16">Floor</a></span>
|
|---|
| 56 | <br />   <span class="subsubsectionToc" >1.2.5 <a
|
|---|
| 57 | href="#x1-160001.2.5" id="QQ2-1-17">Residue</a></span>
|
|---|
| 58 | <br />   <span class="subsubsectionToc" >1.2.6 <a
|
|---|
| 59 | href="#x1-170001.2.6" id="QQ2-1-18">Codebooks</a></span>
|
|---|
| 60 | <br />  <span class="subsectionToc" >1.3 <a
|
|---|
| 61 | href="#x1-180001.3" id="QQ2-1-19">High-level Decode Process</a></span>
|
|---|
| 62 | <br />   <span class="subsubsectionToc" >1.3.1 <a
|
|---|
| 63 | href="#x1-190001.3.1" id="QQ2-1-20">Decode Setup</a></span>
|
|---|
| 64 | <br />   <span class="subsubsectionToc" >1.3.2 <a
|
|---|
| 65 | href="#x1-230001.3.2" id="QQ2-1-24">Decode Procedure</a></span>
|
|---|
| 66 | <br /> <span class="sectionToc" >2 <a
|
|---|
| 67 | href="#x1-360002" id="QQ2-1-39">Bitpacking Convention</a></span>
|
|---|
| 68 | <br />  <span class="subsectionToc" >2.1 <a
|
|---|
| 69 | href="#x1-370002.1" id="QQ2-1-40">Overview</a></span>
|
|---|
| 70 | <br />   <span class="subsubsectionToc" >2.1.1 <a
|
|---|
| 71 | href="#x1-380002.1.1" id="QQ2-1-41">octets, bytes and words</a></span>
|
|---|
| 72 | <br />   <span class="subsubsectionToc" >2.1.2 <a
|
|---|
| 73 | href="#x1-390002.1.2" id="QQ2-1-42">bit order</a></span>
|
|---|
| 74 | <br />   <span class="subsubsectionToc" >2.1.3 <a
|
|---|
| 75 | href="#x1-400002.1.3" id="QQ2-1-43">byte order</a></span>
|
|---|
| 76 | <br />   <span class="subsubsectionToc" >2.1.4 <a
|
|---|
| 77 | href="#x1-410002.1.4" id="QQ2-1-44">coding bits into byte sequences</a></span>
|
|---|
| 78 | <br />   <span class="subsubsectionToc" >2.1.5 <a
|
|---|
| 79 | href="#x1-420002.1.5" id="QQ2-1-45">signedness</a></span>
|
|---|
| 80 | <br />   <span class="subsubsectionToc" >2.1.6 <a
|
|---|
| 81 | href="#x1-430002.1.6" id="QQ2-1-46">coding example</a></span>
|
|---|
| 82 | <br />   <span class="subsubsectionToc" >2.1.7 <a
|
|---|
| 83 | href="#x1-440002.1.7" id="QQ2-1-47">decoding example</a></span>
|
|---|
| 84 | <br />   <span class="subsubsectionToc" >2.1.8 <a
|
|---|
| 85 | href="#x1-450002.1.8" id="QQ2-1-48">end-of-packet alignment</a></span>
|
|---|
| 86 | <br />   <span class="subsubsectionToc" >2.1.9 <a
|
|---|
| 87 | href="#x1-460002.1.9" id="QQ2-1-49">reading zero bits</a></span>
|
|---|
| 88 | <br /> <span class="sectionToc" >3 <a
|
|---|
| 89 | href="#x1-470003" id="QQ2-1-50">Probability Model and Codebooks</a></span>
|
|---|
| 90 | <br />  <span class="subsectionToc" >3.1 <a
|
|---|
| 91 | href="#x1-480003.1" id="QQ2-1-51">Overview</a></span>
|
|---|
| 92 | <br />   <span class="subsubsectionToc" >3.1.1 <a
|
|---|
| 93 | href="#x1-490003.1.1" id="QQ2-1-52">Bitwise operation</a></span>
|
|---|
| 94 | <br />  <span class="subsectionToc" >3.2 <a
|
|---|
| 95 | href="#x1-500003.2" id="QQ2-1-53">Packed codebook format</a></span>
|
|---|
| 96 | <br />   <span class="subsubsectionToc" >3.2.1 <a
|
|---|
| 97 | href="#x1-510003.2.1" id="QQ2-1-54">codebook decode</a></span>
|
|---|
| 98 | <br />  <span class="subsectionToc" >3.3 <a
|
|---|
| 99 | href="#x1-580003.3" id="QQ2-1-63">Use of the codebook abstraction</a></span>
|
|---|
| 100 | <br /> <span class="sectionToc" >4 <a
|
|---|
| 101 | href="#x1-590004" id="QQ2-1-64">Codec Setup and Packet Decode</a></span>
|
|---|
| 102 | <br />  <span class="subsectionToc" >4.1 <a
|
|---|
| 103 | href="#x1-600004.1" id="QQ2-1-65">Overview</a></span>
|
|---|
| 104 | <br />  <span class="subsectionToc" >4.2 <a
|
|---|
| 105 | href="#x1-610004.2" id="QQ2-1-66">Header decode and decode setup</a></span>
|
|---|
| 106 | <br />   <span class="subsubsectionToc" >4.2.1 <a
|
|---|
| 107 | href="#x1-620004.2.1" id="QQ2-1-67">Common header decode</a></span>
|
|---|
| 108 | <br />   <span class="subsubsectionToc" >4.2.2 <a
|
|---|
| 109 | href="#x1-630004.2.2" id="QQ2-1-68">Identification header</a></span>
|
|---|
| 110 | <br />   <span class="subsubsectionToc" >4.2.3 <a
|
|---|
| 111 | href="#x1-640004.2.3" id="QQ2-1-69">Comment header</a></span>
|
|---|
| 112 |
|
|---|
| 113 |
|
|---|
| 114 |
|
|---|
| 115 | <br />   <span class="subsubsectionToc" >4.2.4 <a
|
|---|
| 116 | href="#x1-650004.2.4" id="QQ2-1-70">Setup header</a></span>
|
|---|
| 117 | <br />  <span class="subsectionToc" >4.3 <a
|
|---|
| 118 | href="#x1-720004.3" id="QQ2-1-78">Audio packet decode and synthesis</a></span>
|
|---|
| 119 | <br />   <span class="subsubsectionToc" >4.3.1 <a
|
|---|
| 120 | href="#x1-730004.3.1" id="QQ2-1-79">packet type, mode and window decode</a></span>
|
|---|
| 121 | <br />   <span class="subsubsectionToc" >4.3.2 <a
|
|---|
| 122 | href="#x1-740004.3.2" id="QQ2-1-80">floor curve decode</a></span>
|
|---|
| 123 | <br />   <span class="subsubsectionToc" >4.3.3 <a
|
|---|
| 124 | href="#x1-750004.3.3" id="QQ2-1-81">nonzero vector propagate</a></span>
|
|---|
| 125 | <br />   <span class="subsubsectionToc" >4.3.4 <a
|
|---|
| 126 | href="#x1-760004.3.4" id="QQ2-1-82">residue decode</a></span>
|
|---|
| 127 | <br />   <span class="subsubsectionToc" >4.3.5 <a
|
|---|
| 128 | href="#x1-770004.3.5" id="QQ2-1-83">inverse coupling</a></span>
|
|---|
| 129 | <br />   <span class="subsubsectionToc" >4.3.6 <a
|
|---|
| 130 | href="#x1-780004.3.6" id="QQ2-1-84">dot product</a></span>
|
|---|
| 131 | <br />   <span class="subsubsectionToc" >4.3.7 <a
|
|---|
| 132 | href="#x1-790004.3.7" id="QQ2-1-85">inverse MDCT</a></span>
|
|---|
| 133 | <br />   <span class="subsubsectionToc" >4.3.8 <a
|
|---|
| 134 | href="#x1-800004.3.8" id="QQ2-1-86">overlap_add</a></span>
|
|---|
| 135 | <br />   <span class="subsubsectionToc" >4.3.9 <a
|
|---|
| 136 | href="#x1-810004.3.9" id="QQ2-1-87">output channel order</a></span>
|
|---|
| 137 | <br /> <span class="sectionToc" >5 <a
|
|---|
| 138 | href="#x1-820005" id="QQ2-1-88">comment field and header specification</a></span>
|
|---|
| 139 | <br />  <span class="subsectionToc" >5.1 <a
|
|---|
| 140 | href="#x1-830005.1" id="QQ2-1-89">Overview</a></span>
|
|---|
| 141 | <br />  <span class="subsectionToc" >5.2 <a
|
|---|
| 142 | href="#x1-840005.2" id="QQ2-1-90">Comment encoding</a></span>
|
|---|
| 143 | <br />   <span class="subsubsectionToc" >5.2.1 <a
|
|---|
| 144 | href="#x1-850005.2.1" id="QQ2-1-91">Structure</a></span>
|
|---|
| 145 | <br />   <span class="subsubsectionToc" >5.2.2 <a
|
|---|
| 146 | href="#x1-860005.2.2" id="QQ2-1-92">Content vector format</a></span>
|
|---|
| 147 | <br />   <span class="subsubsectionToc" >5.2.3 <a
|
|---|
| 148 | href="#x1-890005.2.3" id="QQ2-1-95">Encoding</a></span>
|
|---|
| 149 | <br /> <span class="sectionToc" >6 <a
|
|---|
| 150 | href="#x1-900006" id="QQ2-1-96">Floor type 0 setup and decode</a></span>
|
|---|
| 151 | <br />  <span class="subsectionToc" >6.1 <a
|
|---|
| 152 | href="#x1-910006.1" id="QQ2-1-97">Overview</a></span>
|
|---|
| 153 | <br />  <span class="subsectionToc" >6.2 <a
|
|---|
| 154 | href="#x1-920006.2" id="QQ2-1-98">Floor 0 format</a></span>
|
|---|
| 155 | <br />   <span class="subsubsectionToc" >6.2.1 <a
|
|---|
| 156 | href="#x1-930006.2.1" id="QQ2-1-99">header decode</a></span>
|
|---|
| 157 | <br />   <span class="subsubsectionToc" >6.2.2 <a
|
|---|
| 158 | href="#x1-940006.2.2" id="QQ2-1-100">packet decode</a></span>
|
|---|
| 159 | <br />   <span class="subsubsectionToc" >6.2.3 <a
|
|---|
| 160 | href="#x1-950006.2.3" id="QQ2-1-101">curve computation</a></span>
|
|---|
| 161 | <br /> <span class="sectionToc" >7 <a
|
|---|
| 162 | href="#x1-970007" id="QQ2-1-103">Floor type 1 setup and decode</a></span>
|
|---|
| 163 | <br />  <span class="subsectionToc" >7.1 <a
|
|---|
| 164 | href="#x1-980007.1" id="QQ2-1-104">Overview</a></span>
|
|---|
| 165 | <br />  <span class="subsectionToc" >7.2 <a
|
|---|
| 166 | href="#x1-990007.2" id="QQ2-1-105">Floor 1 format</a></span>
|
|---|
| 167 | <br />   <span class="subsubsectionToc" >7.2.1 <a
|
|---|
| 168 | href="#x1-1000007.2.1" id="QQ2-1-106">model</a></span>
|
|---|
| 169 | <br />   <span class="subsubsectionToc" >7.2.2 <a
|
|---|
| 170 | href="#x1-1010007.2.2" id="QQ2-1-111">header decode</a></span>
|
|---|
| 171 | <br />   <span class="subsubsectionToc" >7.2.3 <a
|
|---|
| 172 | href="#x1-1020007.2.3" id="QQ2-1-112">packet decode</a></span>
|
|---|
| 173 |
|
|---|
| 174 |
|
|---|
| 175 |
|
|---|
| 176 | <br />   <span class="subsubsectionToc" >7.2.4 <a
|
|---|
| 177 | href="#x1-1030007.2.4" id="QQ2-1-113">curve computation</a></span>
|
|---|
| 178 | <br /> <span class="sectionToc" >8 <a
|
|---|
| 179 | href="#x1-1040008" id="QQ2-1-114">Residue setup and decode</a></span>
|
|---|
| 180 | <br />  <span class="subsectionToc" >8.1 <a
|
|---|
| 181 | href="#x1-1050008.1" id="QQ2-1-115">Overview</a></span>
|
|---|
| 182 | <br />  <span class="subsectionToc" >8.2 <a
|
|---|
| 183 | href="#x1-1060008.2" id="QQ2-1-116">Residue format</a></span>
|
|---|
| 184 | <br />  <span class="subsectionToc" >8.3 <a
|
|---|
| 185 | href="#x1-1070008.3" id="QQ2-1-118">residue 0</a></span>
|
|---|
| 186 | <br />  <span class="subsectionToc" >8.4 <a
|
|---|
| 187 | href="#x1-1080008.4" id="QQ2-1-119">residue 1</a></span>
|
|---|
| 188 | <br />  <span class="subsectionToc" >8.5 <a
|
|---|
| 189 | href="#x1-1090008.5" id="QQ2-1-120">residue 2</a></span>
|
|---|
| 190 | <br />  <span class="subsectionToc" >8.6 <a
|
|---|
| 191 | href="#x1-1100008.6" id="QQ2-1-122">Residue decode</a></span>
|
|---|
| 192 | <br />   <span class="subsubsectionToc" >8.6.1 <a
|
|---|
| 193 | href="#x1-1110008.6.1" id="QQ2-1-123">header decode</a></span>
|
|---|
| 194 | <br />   <span class="subsubsectionToc" >8.6.2 <a
|
|---|
| 195 | href="#x1-1120008.6.2" id="QQ2-1-124">packet decode</a></span>
|
|---|
| 196 | <br />   <span class="subsubsectionToc" >8.6.3 <a
|
|---|
| 197 | href="#x1-1130008.6.3" id="QQ2-1-125">format 0 specifics</a></span>
|
|---|
| 198 | <br />   <span class="subsubsectionToc" >8.6.4 <a
|
|---|
| 199 | href="#x1-1140008.6.4" id="QQ2-1-126">format 1 specifics</a></span>
|
|---|
| 200 | <br />   <span class="subsubsectionToc" >8.6.5 <a
|
|---|
| 201 | href="#x1-1150008.6.5" id="QQ2-1-127">format 2 specifics</a></span>
|
|---|
| 202 | <br /> <span class="sectionToc" >9 <a
|
|---|
| 203 | href="#x1-1160009" id="QQ2-1-128">Helper equations</a></span>
|
|---|
| 204 | <br />  <span class="subsectionToc" >9.1 <a
|
|---|
| 205 | href="#x1-1170009.1" id="QQ2-1-129">Overview</a></span>
|
|---|
| 206 | <br />  <span class="subsectionToc" >9.2 <a
|
|---|
| 207 | href="#x1-1180009.2" id="QQ2-1-130">Functions</a></span>
|
|---|
| 208 | <br />   <span class="subsubsectionToc" >9.2.1 <a
|
|---|
| 209 | href="#x1-1190009.2.1" id="QQ2-1-131">ilog</a></span>
|
|---|
| 210 | <br />   <span class="subsubsectionToc" >9.2.2 <a
|
|---|
| 211 | href="#x1-1200009.2.2" id="QQ2-1-132">float32_unpack</a></span>
|
|---|
| 212 | <br />   <span class="subsubsectionToc" >9.2.3 <a
|
|---|
| 213 | href="#x1-1210009.2.3" id="QQ2-1-133">lookup1_values</a></span>
|
|---|
| 214 | <br />   <span class="subsubsectionToc" >9.2.4 <a
|
|---|
| 215 | href="#x1-1220009.2.4" id="QQ2-1-134">low_neighbor</a></span>
|
|---|
| 216 | <br />   <span class="subsubsectionToc" >9.2.5 <a
|
|---|
| 217 | href="#x1-1230009.2.5" id="QQ2-1-135">high_neighbor</a></span>
|
|---|
| 218 | <br />   <span class="subsubsectionToc" >9.2.6 <a
|
|---|
| 219 | href="#x1-1240009.2.6" id="QQ2-1-136">render_point</a></span>
|
|---|
| 220 | <br />   <span class="subsubsectionToc" >9.2.7 <a
|
|---|
| 221 | href="#x1-1250009.2.7" id="QQ2-1-137">render_line</a></span>
|
|---|
| 222 | <br /> <span class="sectionToc" >10 <a
|
|---|
| 223 | href="#x1-12600010" id="QQ2-1-138">Tables</a></span>
|
|---|
| 224 | <br />  <span class="subsectionToc" >10.1 <a
|
|---|
| 225 | href="#x1-12700010.1" id="QQ2-1-139">floor1_inverse_dB_table</a></span>
|
|---|
| 226 | <br /> <span class="sectionToc" >A <a
|
|---|
| 227 | href="#x1-128000A" id="QQ2-1-140">Embedding Vorbis into an Ogg stream</a></span>
|
|---|
| 228 | <br />  <span class="subsectionToc" >A.1 <a
|
|---|
| 229 | href="#x1-129000A.1" id="QQ2-1-141">Overview</a></span>
|
|---|
| 230 | <br />   <span class="subsubsectionToc" >A.1.1 <a
|
|---|
| 231 | href="#x1-130000A.1.1" id="QQ2-1-142">Restrictions</a></span>
|
|---|
| 232 | <br />   <span class="subsubsectionToc" >A.1.2 <a
|
|---|
| 233 | href="#x1-131000A.1.2" id="QQ2-1-143">MIME type</a></span>
|
|---|
| 234 |
|
|---|
| 235 |
|
|---|
| 236 |
|
|---|
| 237 | <br />  <span class="subsectionToc" >A.2 <a
|
|---|
| 238 | href="#x1-132000A.2" id="QQ2-1-144">Encapsulation</a></span>
|
|---|
| 239 | <br /> <span class="sectionToc" >B <a
|
|---|
| 240 | href="#x1-134000B" id="QQ2-1-146">Vorbis encapsulation in RTP</a></span>
|
|---|
| 241 | </div>
|
|---|
| 242 |
|
|---|
| 243 |
|
|---|
| 244 |
|
|---|
| 245 | <h3 class="sectionHead"><span class="titlemark">1. </span> <a
|
|---|
| 246 | id="x1-20001"></a>Introduction and Description</h3>
|
|---|
| 247 | <!--l. 5--><p class="noindent" >
|
|---|
| 248 | <h4 class="subsectionHead"><span class="titlemark">1.1. </span> <a
|
|---|
| 249 | id="x1-30001.1"></a>Overview</h4>
|
|---|
| 250 | <!--l. 7--><p class="noindent" >This document provides a high level description of the Vorbis codec’s construction. A bit-by-bit
|
|---|
| 251 | specification appears beginning in <a
|
|---|
| 252 | href="#x1-590004">section 4</a>, “<a
|
|---|
| 253 | href="#x1-590004">Codec Setup and Packet Decode<!--tex4ht:ref: vorbis:spec:codec --></a>”. The later
|
|---|
| 254 | sections assume a high-level understanding of the Vorbis decode process, which is provided
|
|---|
| 255 | here.
|
|---|
| 256 | <!--l. 14--><p class="noindent" >
|
|---|
| 257 | <h5 class="subsubsectionHead"><span class="titlemark">1.1.1. </span> <a
|
|---|
| 258 | id="x1-40001.1.1"></a>Application</h5>
|
|---|
| 259 | <!--l. 15--><p class="noindent" >Vorbis is a general purpose perceptual audio CODEC intended to allow maximum encoder
|
|---|
| 260 | flexibility, thus allowing it to scale competitively over an exceptionally wide range of bitrates. At
|
|---|
| 261 | the high quality/bitrate end of the scale (CD or DAT rate stereo, 16/24 bits) it is in the same
|
|---|
| 262 | league as MPEG-2 and MPC. Similarly, the 1.0 encoder can encode high-quality CD and DAT
|
|---|
| 263 | rate stereo at below 48kbps without resampling to a lower rate. Vorbis is also intended for lower
|
|---|
| 264 | and higher sample rates (from 8kHz telephony to 192kHz digital masters) and a range of channel
|
|---|
| 265 | representations (monaural, polyphonic, stereo, quadraphonic, 5.1, ambisonic, or up to 255
|
|---|
| 266 | discrete channels).
|
|---|
| 267 | <!--l. 28--><p class="noindent" >
|
|---|
| 268 | <h5 class="subsubsectionHead"><span class="titlemark">1.1.2. </span> <a
|
|---|
| 269 | id="x1-50001.1.2"></a>Classification</h5>
|
|---|
| 270 | <!--l. 29--><p class="noindent" >Vorbis I is a forward-adaptive monolithic transform CODEC based on the Modified Discrete
|
|---|
| 271 | Cosine Transform. The codec is structured to allow addition of a hybrid wavelet filterbank in
|
|---|
| 272 | Vorbis II to offer better transient response and reproduction using a transform better suited to
|
|---|
| 273 | localized time events.
|
|---|
| 274 |
|
|---|
| 275 |
|
|---|
| 276 |
|
|---|
| 277 | <!--l. 36--><p class="noindent" >
|
|---|
| 278 | <h5 class="subsubsectionHead"><span class="titlemark">1.1.3. </span> <a
|
|---|
| 279 | id="x1-60001.1.3"></a>Assumptions</h5>
|
|---|
| 280 | <!--l. 38--><p class="noindent" >The Vorbis CODEC design assumes a complex, psychoacoustically-aware encoder and simple,
|
|---|
| 281 | low-complexity decoder. Vorbis decode is computationally simpler than mp3, although it does
|
|---|
| 282 | require more working memory as Vorbis has no static probability model; the vector codebooks
|
|---|
| 283 | used in the first stage of decoding from the bitstream are packed in their entirety into the Vorbis
|
|---|
| 284 | bitstream headers. In packed form, these codebooks occupy only a few kilobytes; the extent to
|
|---|
| 285 | which they are pre-decoded into a cache is the dominant factor in decoder memory
|
|---|
| 286 | usage.
|
|---|
| 287 | <!--l. 49--><p class="noindent" >Vorbis provides none of its own framing, synchronization or protection against errors; it
|
|---|
| 288 | is solely a method of accepting input audio, dividing it into individual frames and
|
|---|
| 289 | compressing these frames into raw, unformatted ’packets’. The decoder then accepts
|
|---|
| 290 | these raw packets in sequence, decodes them, synthesizes audio frames from them, and
|
|---|
| 291 | reassembles the frames into a facsimile of the original audio stream. Vorbis is a free-form
|
|---|
| 292 | variable bit rate (VBR) codec and packets have no minimum size, maximum size, or
|
|---|
| 293 | fixed/expected size. Packets are designed that they may be truncated (or padded)
|
|---|
| 294 | and remain decodable; this is not to be considered an error condition and is used
|
|---|
| 295 | extensively in bitrate management in peeling. Both the transport mechanism and
|
|---|
| 296 | decoder must allow that a packet may be any size, or end before or after packet decode
|
|---|
| 297 | expects.
|
|---|
| 298 | <!--l. 63--><p class="noindent" >Vorbis packets are thus intended to be used with a transport mechanism that provides free-form
|
|---|
| 299 | framing, sync, positioning and error correction in accordance with these design assumptions, such
|
|---|
| 300 | as Ogg (for file transport) or RTP (for network multicast). For purposes of a few examples in this
|
|---|
| 301 | document, we will assume that Vorbis is to be embedded in an Ogg stream specifically,
|
|---|
| 302 | although this is by no means a requirement or fundamental assumption in the Vorbis
|
|---|
| 303 | design.
|
|---|
| 304 | <!--l. 71--><p class="noindent" >The specification for embedding Vorbis into an Ogg transport stream is in <a
|
|---|
| 305 | href="#x1-128000A">section A</a>,
|
|---|
| 306 | “<a
|
|---|
| 307 | href="#x1-128000A">Embedding Vorbis into an Ogg stream<!--tex4ht:ref: vorbis:over:ogg --></a>”.
|
|---|
| 308 | <!--l. 76--><p class="noindent" >
|
|---|
| 309 | <h5 class="subsubsectionHead"><span class="titlemark">1.1.4. </span> <a
|
|---|
| 310 | id="x1-70001.1.4"></a>Codec Setup and Probability Model</h5>
|
|---|
| 311 | <!--l. 78--><p class="noindent" >Vorbis’ heritage is as a research CODEC and its current design reflects a desire to allow multiple
|
|---|
| 312 | decades of continuous encoder improvement before running out of room within the codec
|
|---|
| 313 | specification. For these reasons, configurable aspects of codec setup intentionally lean toward the
|
|---|
| 314 | extreme of forward adaptive.
|
|---|
| 315 |
|
|---|
| 316 |
|
|---|
| 317 |
|
|---|
| 318 | <!--l. 84--><p class="noindent" >The single most controversial design decision in Vorbis (and the most unusual for a Vorbis
|
|---|
| 319 | developer to keep in mind) is that the entire probability model of the codec, the Huffman and
|
|---|
| 320 | VQ codebooks, is packed into the bitstream header along with extensive CODEC setup
|
|---|
| 321 | parameters (often several hundred fields). This makes it impossible, as it would be with
|
|---|
| 322 | MPEG audio layers, to embed a simple frame type flag in each audio packet, or begin
|
|---|
| 323 | decode at any frame in the stream without having previously fetched the codec setup
|
|---|
| 324 | header.
|
|---|
| 325 | <!--l. 94--><p class="noindent" ><span class="likesubparagraphHead"><a
|
|---|
| 326 | id="x1-80001.1.4"></a><span
|
|---|
| 327 | class="cmbx-12">Note:</span></span> Vorbis <span
|
|---|
| 328 | class="cmti-12">can </span>initiate decode at any arbitrary packet within a bitstream so long as the codec
|
|---|
| 329 | has been initialized/setup with the setup headers.
|
|---|
| 330 | <!--l. 100--><p class="noindent" >Thus, Vorbis headers are both required for decode to begin and relatively large as bitstream
|
|---|
| 331 | headers go. The header size is unbounded, although for streaming a rule-of-thumb of 4kB or less
|
|---|
| 332 | is recommended (and Xiph.Org’s Vorbis encoder follows this suggestion).
|
|---|
| 333 | <!--l. 105--><p class="noindent" >Our own design work indicates the primary liability of the required header is in mindshare; it is
|
|---|
| 334 | an unusual design and thus causes some amount of complaint among engineers as this runs
|
|---|
| 335 | against current design trends (and also points out limitations in some existing software/interface
|
|---|
| 336 | designs, such as Windows’ ACM codec framework). However, we find that it does not
|
|---|
| 337 | fundamentally limit Vorbis’ suitable application space.
|
|---|
| 338 | <!--l. 114--><p class="noindent" >
|
|---|
| 339 | <h5 class="subsubsectionHead"><span class="titlemark">1.1.5. </span> <a
|
|---|
| 340 | id="x1-90001.1.5"></a>Format Specification</h5>
|
|---|
| 341 | <!--l. 115--><p class="noindent" >The Vorbis format is well-defined by its decode specification; any encoder that produces packets
|
|---|
| 342 | that are correctly decoded by the reference Vorbis decoder described below may be considered
|
|---|
| 343 | a proper Vorbis encoder. A decoder must faithfully and completely implement the
|
|---|
| 344 | specification defined below (except where noted) to be considered a proper Vorbis
|
|---|
| 345 | decoder.
|
|---|
| 346 | <!--l. 122--><p class="noindent" >
|
|---|
| 347 | <h5 class="subsubsectionHead"><span class="titlemark">1.1.6. </span> <a
|
|---|
| 348 | id="x1-100001.1.6"></a>Hardware Profile</h5>
|
|---|
| 349 |
|
|---|
| 350 |
|
|---|
| 351 |
|
|---|
| 352 | <!--l. 123--><p class="noindent" >Although Vorbis decode is computationally simple, it may still run into specific limitations of an
|
|---|
| 353 | embedded design. For this reason, embedded designs are allowed to deviate in limited ways from
|
|---|
| 354 | the ‘full’ decode specification yet still be certified compliant. These optional omissions are
|
|---|
| 355 | labelled in the spec where relevant.
|
|---|
| 356 | <!--l. 130--><p class="noindent" >
|
|---|
| 357 | <h4 class="subsectionHead"><span class="titlemark">1.2. </span> <a
|
|---|
| 358 | id="x1-110001.2"></a>Decoder Configuration</h4>
|
|---|
| 359 | <!--l. 132--><p class="noindent" >Decoder setup consists of configuration of multiple, self-contained component abstractions that
|
|---|
| 360 | perform specific functions in the decode pipeline. Each different component instance of a specific
|
|---|
| 361 | type is semantically interchangeable; decoder configuration consists both of internal component
|
|---|
| 362 | configuration, as well as arrangement of specific instances into a decode pipeline. Componentry
|
|---|
| 363 | arrangement is roughly as follows:
|
|---|
| 364 | <div class="center"
|
|---|
| 365 | >
|
|---|
| 366 | <!--l. 140--><p class="noindent" >
|
|---|
| 367 |
|
|---|
| 368 | <!--l. 141--><p class="noindent" ><img
|
|---|
| 369 | src="components.png" alt="PIC"
|
|---|
| 370 | >
|
|---|
| 371 | <br /> <div class="caption"
|
|---|
| 372 | ><span class="id">Figure 1: </span><span
|
|---|
| 373 | class="content">decoder pipeline configuration</span></div><!--tex4ht:label?: x1-110011 -->
|
|---|
| 374 | </div>
|
|---|
| 375 | <!--l. 145--><p class="noindent" >
|
|---|
| 376 | <h5 class="subsubsectionHead"><span class="titlemark">1.2.1. </span> <a
|
|---|
| 377 | id="x1-120001.2.1"></a>Global Config</h5>
|
|---|
| 378 | <!--l. 146--><p class="noindent" >Global codec configuration consists of a few audio related fields (sample rate, channels), Vorbis
|
|---|
| 379 | version (always ’0’ in Vorbis I), bitrate hints, and the lists of component instances. All other
|
|---|
| 380 | configuration is in the context of specific components.
|
|---|
| 381 | <!--l. 151--><p class="noindent" >
|
|---|
| 382 | <h5 class="subsubsectionHead"><span class="titlemark">1.2.2. </span> <a
|
|---|
| 383 | id="x1-130001.2.2"></a>Mode</h5>
|
|---|
| 384 |
|
|---|
| 385 |
|
|---|
| 386 |
|
|---|
| 387 | <!--l. 153--><p class="noindent" >Each Vorbis frame is coded according to a master ’mode’. A bitstream may use one or many
|
|---|
| 388 | modes.
|
|---|
| 389 | <!--l. 156--><p class="noindent" >The mode mechanism is used to encode a frame according to one of multiple possible
|
|---|
| 390 | methods with the intention of choosing a method best suited to that frame. Different
|
|---|
| 391 | modes are, e.g. how frame size is changed from frame to frame. The mode number of a
|
|---|
| 392 | frame serves as a top level configuration switch for all other specific aspects of frame
|
|---|
| 393 | decode.
|
|---|
| 394 | <!--l. 163--><p class="noindent" >A ’mode’ configuration consists of a frame size setting, window type (always 0, the Vorbis
|
|---|
| 395 | window, in Vorbis I), transform type (always type 0, the MDCT, in Vorbis I) and a mapping
|
|---|
| 396 | number. The mapping number specifies which mapping configuration instance to use for low-level
|
|---|
| 397 | packet decode and synthesis.
|
|---|
| 398 | <!--l. 170--><p class="noindent" >
|
|---|
| 399 | <h5 class="subsubsectionHead"><span class="titlemark">1.2.3. </span> <a
|
|---|
| 400 | id="x1-140001.2.3"></a>Mapping</h5>
|
|---|
| 401 | <!--l. 172--><p class="noindent" >A mapping contains a channel coupling description and a list of ’submaps’ that bundle sets
|
|---|
| 402 | of channel vectors together for grouped encoding and decoding. These submaps are
|
|---|
| 403 | not references to external components; the submap list is internal and specific to a
|
|---|
| 404 | mapping.
|
|---|
| 405 | <!--l. 177--><p class="noindent" >A ’submap’ is a configuration/grouping that applies to a subset of floor and residue vectors
|
|---|
| 406 | within a mapping. The submap functions as a last layer of indirection such that specific special
|
|---|
| 407 | floor or residue settings can be applied not only to all the vectors in a given mode, but also
|
|---|
| 408 | specific vectors in a specific mode. Each submap specifies the proper floor and residue
|
|---|
| 409 | instance number to use for decoding that submap’s spectral floor and spectral residue
|
|---|
| 410 | vectors.
|
|---|
| 411 | <!--l. 185--><p class="noindent" >As an example:
|
|---|
| 412 | <!--l. 187--><p class="noindent" >Assume a Vorbis stream that contains six channels in the standard 5.1 format. The sixth
|
|---|
| 413 | channel, as is normal in 5.1, is bass only. Therefore it would be wasteful to encode a
|
|---|
| 414 | full-spectrum version of it as with the other channels. The submapping mechanism can be used
|
|---|
| 415 | to apply a full range floor and residue encoding to channels 0 through 4, and a bass-only
|
|---|
| 416 | representation to the bass channel, thus saving space. In this example, channels 0-4 belong to
|
|---|
| 417 | submap 0 (which indicates use of a full-range floor) and channel 5 belongs to submap 1, which
|
|---|
| 418 | uses a bass-only representation.
|
|---|
| 419 |
|
|---|
| 420 |
|
|---|
| 421 |
|
|---|
| 422 | <!--l. 198--><p class="noindent" >
|
|---|
| 423 | <h5 class="subsubsectionHead"><span class="titlemark">1.2.4. </span> <a
|
|---|
| 424 | id="x1-150001.2.4"></a>Floor</h5>
|
|---|
| 425 | <!--l. 200--><p class="noindent" >Vorbis encodes a spectral ’floor’ vector for each PCM channel. This vector is a low-resolution
|
|---|
| 426 | representation of the audio spectrum for the given channel in the current frame, generally used
|
|---|
| 427 | akin to a whitening filter. It is named a ’floor’ because the Xiph.Org reference encoder has
|
|---|
| 428 | historically used it as a unit-baseline for spectral resolution.
|
|---|
| 429 | <!--l. 207--><p class="noindent" >A floor encoding may be of two types. Floor 0 uses a packed LSP representation on a dB
|
|---|
| 430 | amplitude scale and Bark frequency scale. Floor 1 represents the curve as a piecewise linear
|
|---|
| 431 | interpolated representation on a dB amplitude scale and linear frequency scale. The two floors
|
|---|
| 432 | are semantically interchangeable in encoding/decoding. However, floor type 1 provides more
|
|---|
| 433 | stable inter-frame behavior, and so is the preferred choice in all coupled-stereo and
|
|---|
| 434 | high bitrate modes. Floor 1 is also considerably less expensive to decode than floor
|
|---|
| 435 | 0.
|
|---|
| 436 | <!--l. 217--><p class="noindent" >Floor 0 is not to be considered deprecated, but it is of limited modern use. No known Vorbis
|
|---|
| 437 | encoder past Xiph.Org’s own beta 4 makes use of floor 0.
|
|---|
| 438 | <!--l. 221--><p class="noindent" >The values coded/decoded by a floor are both compactly formatted and make use of entropy
|
|---|
| 439 | coding to save space. For this reason, a floor configuration generally refers to multiple
|
|---|
| 440 | codebooks in the codebook component list. Entropy coding is thus provided as an
|
|---|
| 441 | abstraction, and each floor instance may choose from any and all available codebooks when
|
|---|
| 442 | coding/decoding.
|
|---|
| 443 | <!--l. 229--><p class="noindent" >
|
|---|
| 444 | <h5 class="subsubsectionHead"><span class="titlemark">1.2.5. </span> <a
|
|---|
| 445 | id="x1-160001.2.5"></a>Residue</h5>
|
|---|
| 446 | <!--l. 230--><p class="noindent" >The spectral residue is the fine structure of the audio spectrum once the floor curve has been
|
|---|
| 447 | subtracted out. In simplest terms, it is coded in the bitstream using cascaded (multi-pass) vector
|
|---|
| 448 | quantization according to one of three specific packing/coding algorithms numbered
|
|---|
| 449 | 0 through 2. The packing algorithm details are configured by residue instance. As
|
|---|
| 450 | with the floor components, the final VQ/entropy encoding is provided by external
|
|---|
| 451 | codebook instances and each residue instance may choose from any and all available
|
|---|
| 452 | codebooks.
|
|---|
| 453 | <!--l. 240--><p class="noindent" >
|
|---|
| 454 |
|
|---|
| 455 |
|
|---|
| 456 |
|
|---|
| 457 | <h5 class="subsubsectionHead"><span class="titlemark">1.2.6. </span> <a
|
|---|
| 458 | id="x1-170001.2.6"></a>Codebooks</h5>
|
|---|
| 459 | <!--l. 242--><p class="noindent" >Codebooks are a self-contained abstraction that perform entropy decoding and, optionally, use
|
|---|
| 460 | the entropy-decoded integer value as an offset into an index of output value vectors, returning
|
|---|
| 461 | the indicated vector of values.
|
|---|
| 462 | <!--l. 247--><p class="noindent" >The entropy coding in a Vorbis I codebook is provided by a standard Huffman binary tree
|
|---|
| 463 | representation. This tree is tightly packed using one of several methods, depending on whether
|
|---|
| 464 | codeword lengths are ordered or unordered, or the tree is sparse.
|
|---|
| 465 | <!--l. 252--><p class="noindent" >The codebook vector index is similarly packed according to index characteristic. Most commonly,
|
|---|
| 466 | the vector index is encoded as a single list of values of possible values that are then permuted
|
|---|
| 467 | into a list of n-dimensional rows (lattice VQ).
|
|---|
| 468 | <!--l. 259--><p class="noindent" >
|
|---|
| 469 | <h4 class="subsectionHead"><span class="titlemark">1.3. </span> <a
|
|---|
| 470 | id="x1-180001.3"></a>High-level Decode Process</h4>
|
|---|
| 471 | <!--l. 261--><p class="noindent" >
|
|---|
| 472 | <h5 class="subsubsectionHead"><span class="titlemark">1.3.1. </span> <a
|
|---|
| 473 | id="x1-190001.3.1"></a>Decode Setup</h5>
|
|---|
| 474 | <!--l. 263--><p class="noindent" >Before decoding can begin, a decoder must initialize using the bitstream headers matching the
|
|---|
| 475 | stream to be decoded. Vorbis uses three header packets; all are required, in-order, by
|
|---|
| 476 | this specification. Once set up, decode may begin at any audio packet belonging to
|
|---|
| 477 | the Vorbis stream. In Vorbis I, all packets after the three initial headers are audio
|
|---|
| 478 | packets.
|
|---|
| 479 | <!--l. 270--><p class="noindent" >The header packets are, in order, the identification header, the comments header, and the setup
|
|---|
| 480 | header.
|
|---|
| 481 | <!--l. 273--><p class="noindent" ><span class="paragraphHead"><a
|
|---|
| 482 | id="x1-200001.3.1"></a><span
|
|---|
| 483 | class="cmbx-12">Identification Header</span></span>
|
|---|
| 484 | The identification header identifies the bitstream as Vorbis, Vorbis version, and the simple audio
|
|---|
| 485 | characteristics of the stream such as sample rate and number of channels.
|
|---|
| 486 |
|
|---|
| 487 |
|
|---|
| 488 |
|
|---|
| 489 | <!--l. 278--><p class="noindent" ><span class="paragraphHead"><a
|
|---|
| 490 | id="x1-210001.3.1"></a><span
|
|---|
| 491 | class="cmbx-12">Comment Header</span></span>
|
|---|
| 492 | The comment header includes user text comments (“tags”) and a vendor string for the
|
|---|
| 493 | application/library that produced the bitstream. The encoding and proper use of the comment
|
|---|
| 494 | header is described in <a
|
|---|
| 495 | href="#x1-820005">section 5</a>, “<a
|
|---|
| 496 | href="#x1-820005">comment field and header specification<!--tex4ht:ref: vorbis:spec:comment --></a>”.
|
|---|
| 497 | <!--l. 283--><p class="noindent" ><span class="paragraphHead"><a
|
|---|
| 498 | id="x1-220001.3.1"></a><span
|
|---|
| 499 | class="cmbx-12">Setup Header</span></span>
|
|---|
| 500 | The setup header includes extensive CODEC setup information as well as the complete VQ and
|
|---|
| 501 | Huffman codebooks needed for decode.
|
|---|
| 502 | <!--l. 288--><p class="noindent" >
|
|---|
| 503 | <h5 class="subsubsectionHead"><span class="titlemark">1.3.2. </span> <a
|
|---|
| 504 | id="x1-230001.3.2"></a>Decode Procedure</h5>
|
|---|
| 505 | <!--l. 290--><p class="noindent" >The decoding and synthesis procedure for all audio packets is fundamentally the same.
|
|---|
| 506 | <dl class="enumerate-enumitem"><dt class="enumerate-enumitem">
|
|---|
| 507 | 1. </dt><dd
|
|---|
| 508 | class="enumerate-enumitem">decode packet type flag
|
|---|
| 509 | </dd><dt class="enumerate-enumitem">
|
|---|
| 510 | 2. </dt><dd
|
|---|
| 511 | class="enumerate-enumitem">decode mode number
|
|---|
| 512 | </dd><dt class="enumerate-enumitem">
|
|---|
| 513 | 3. </dt><dd
|
|---|
| 514 | class="enumerate-enumitem">decode window shape (long windows only)
|
|---|
| 515 | </dd><dt class="enumerate-enumitem">
|
|---|
| 516 | 4. </dt><dd
|
|---|
| 517 | class="enumerate-enumitem">decode floor
|
|---|
| 518 | </dd><dt class="enumerate-enumitem">
|
|---|
| 519 | 5. </dt><dd
|
|---|
| 520 | class="enumerate-enumitem">decode residue into residue vectors
|
|---|
| 521 | </dd><dt class="enumerate-enumitem">
|
|---|
| 522 | 6. </dt><dd
|
|---|
| 523 | class="enumerate-enumitem">inverse channel coupling of residue vectors
|
|---|
| 524 | </dd><dt class="enumerate-enumitem">
|
|---|
| 525 | 7. </dt><dd
|
|---|
| 526 | class="enumerate-enumitem">generate floor curve from decoded floor data
|
|---|
| 527 | </dd><dt class="enumerate-enumitem">
|
|---|
| 528 | 8. </dt><dd
|
|---|
| 529 | class="enumerate-enumitem">compute dot product of floor and residue, producing audio spectrum vector
|
|---|
| 530 | </dd><dt class="enumerate-enumitem">
|
|---|
| 531 | 9. </dt><dd
|
|---|
| 532 | class="enumerate-enumitem">inverse monolithic transform of audio spectrum vector, always an MDCT in Vorbis
|
|---|
| 533 | I
|
|---|
| 534 |
|
|---|
| 535 |
|
|---|
| 536 |
|
|---|
| 537 | </dd><dt class="enumerate-enumitem">
|
|---|
| 538 | 10. </dt><dd
|
|---|
| 539 | class="enumerate-enumitem">overlap/add left-hand output of transform with right-hand output of previous frame
|
|---|
| 540 | </dd><dt class="enumerate-enumitem">
|
|---|
| 541 | 11. </dt><dd
|
|---|
| 542 | class="enumerate-enumitem">store right hand-data from transform of current frame for future lapping
|
|---|
| 543 | </dd><dt class="enumerate-enumitem">
|
|---|
| 544 | 12. </dt><dd
|
|---|
| 545 | class="enumerate-enumitem">if not first frame, return results of overlap/add as audio result of current frame</dd></dl>
|
|---|
| 546 | <!--l. 307--><p class="noindent" >Note that clever rearrangement of the synthesis arithmetic is possible; as an example, one can
|
|---|
| 547 | take advantage of symmetries in the MDCT to store the right-hand transform data of a partial
|
|---|
| 548 | MDCT for a 50% inter-frame buffer space savings, and then complete the transform later before
|
|---|
| 549 | overlap/add with the next frame. This optimization produces entirely equivalent output and is
|
|---|
| 550 | naturally perfectly legal. The decoder must be <span
|
|---|
| 551 | class="cmti-12">entirely mathematically equivalent </span>to the
|
|---|
| 552 | specification, it need not be a literal semantic implementation.
|
|---|
| 553 | <!--l. 316--><p class="noindent" ><span class="paragraphHead"><a
|
|---|
| 554 | id="x1-240001.3.2"></a><span
|
|---|
| 555 | class="cmbx-12">Packet type decode</span></span>
|
|---|
| 556 | Vorbis I uses four packet types. The first three packet types mark each of the three Vorbis
|
|---|
| 557 | headers described above. The fourth packet type marks an audio packet. All other packet types
|
|---|
| 558 | are reserved; packets marked with a reserved type should be ignored.
|
|---|
| 559 | <!--l. 323--><p class="noindent" >Following the three header packets, all packets in a Vorbis I stream are audio. The first step of
|
|---|
| 560 | audio packet decode is to read and verify the packet type; <span
|
|---|
| 561 | class="cmti-12">a non-audio packet when audio is</span>
|
|---|
| 562 | <span
|
|---|
| 563 | class="cmti-12">expected indicates stream corruption or a non-compliant stream. The decoder must ignore the</span>
|
|---|
| 564 | <span
|
|---|
| 565 | class="cmti-12">packet and not attempt decoding it to audio</span>.
|
|---|
| 566 | <!--l. 333--><p class="noindent" ><span class="paragraphHead"><a
|
|---|
| 567 | id="x1-250001.3.2"></a><span
|
|---|
| 568 | class="cmbx-12">Mode decode</span></span>
|
|---|
| 569 | Vorbis allows an encoder to set up multiple, numbered packet ’modes’, as described earlier, all of
|
|---|
| 570 | which may be used in a given Vorbis stream. The mode is encoded as an integer used as a direct
|
|---|
| 571 | offset into the mode instance index.
|
|---|
| 572 | <!--l. 340--><p class="noindent" ><span class="paragraphHead"><a
|
|---|
| 573 | id="x1-260001.3.2"></a><span
|
|---|
| 574 | class="cmbx-12">Window shape decode (long windows only)</span></span>
|
|---|
| 575 | Vorbis frames may be one of two PCM sample sizes specified during codec setup. In Vorbis I,
|
|---|
| 576 | legal frame sizes are powers of two from 64 to 8192 samples. Aside from coupling, Vorbis
|
|---|
| 577 | handles channels as independent vectors and these frame sizes are in samples per
|
|---|
| 578 | channel.
|
|---|
| 579 |
|
|---|
| 580 |
|
|---|
| 581 |
|
|---|
| 582 | <!--l. 347--><p class="noindent" >Vorbis uses an overlapping transform, namely the MDCT, to blend one frame into the next,
|
|---|
| 583 | avoiding most inter-frame block boundary artifacts. The MDCT output of one frame is windowed
|
|---|
| 584 | according to MDCT requirements, overlapped 50% with the output of the previous frame and
|
|---|
| 585 | added. The window shape assures seamless reconstruction.
|
|---|
| 586 | <!--l. 353--><p class="noindent" >This is easy to visualize in the case of equal sized-windows:
|
|---|
| 587 | <div class="center"
|
|---|
| 588 | >
|
|---|
| 589 | <!--l. 355--><p class="noindent" >
|
|---|
| 590 |
|
|---|
| 591 | <!--l. 356--><p class="noindent" ><img
|
|---|
| 592 | src="window1.png" alt="PIC"
|
|---|
| 593 | >
|
|---|
| 594 | <br /> <div class="caption"
|
|---|
| 595 | ><span class="id">Figure 2: </span><span
|
|---|
| 596 | class="content">overlap of two equal-sized windows</span></div><!--tex4ht:label?: x1-260012 -->
|
|---|
| 597 | </div>
|
|---|
| 598 | <!--l. 360--><p class="noindent" >And slightly more complex in the case of overlapping unequal sized windows:
|
|---|
| 599 | <div class="center"
|
|---|
| 600 | >
|
|---|
| 601 | <!--l. 363--><p class="noindent" >
|
|---|
| 602 |
|
|---|
| 603 | <!--l. 364--><p class="noindent" ><img
|
|---|
| 604 | src="window2.png" alt="PIC"
|
|---|
| 605 | >
|
|---|
| 606 | <br /> <div class="caption"
|
|---|
| 607 | ><span class="id">Figure 3: </span><span
|
|---|
| 608 | class="content">overlap of a long and a short window</span></div><!--tex4ht:label?: x1-260023 -->
|
|---|
| 609 | </div>
|
|---|
| 610 | <!--l. 368--><p class="noindent" >In the unequal-sized window case, the window shape of the long window must be modified for
|
|---|
| 611 | seamless lapping as above. It is possible to correctly infer window shape to be applied to the
|
|---|
| 612 | current window from knowing the sizes of the current, previous and next window. It is legal for a
|
|---|
| 613 | decoder to use this method. However, in the case of a long window (short windows require no
|
|---|
| 614 | modification), Vorbis also codes two flag bits to specify pre- and post- window shape. Although
|
|---|
| 615 | not strictly necessary for function, this minor redundancy allows a packet to be fully decoded to
|
|---|
| 616 | the point of lapping entirely independently of any other packet, allowing easier abstraction of
|
|---|
| 617 | decode layers as well as allowing a greater level of easy parallelism in encode and
|
|---|
| 618 | decode.
|
|---|
| 619 | <!--l. 381--><p class="noindent" >A description of valid window functions for use with an inverse MDCT can be found in <span class="cite">[<a
|
|---|
| 620 | href="#XSporer/Brandenburg/Edler">1</a>]</span>.
|
|---|
| 621 | Vorbis windows all use the slope function
|
|---|
| 622 | <center class="math-display" >
|
|---|
| 623 | <img
|
|---|
| 624 | src="Vorbis_I_spec0x.png" alt="y = sin (.5 * π sin2((x + .5)∕n * π)).
|
|---|
| 625 |
|
|---|
| 626 |
|
|---|
| 627 |
|
|---|
| 628 | " class="math-display" ></center>
|
|---|
| 629 | <!--l. 384--><p class="nopar" >
|
|---|
| 630 | <!--l. 388--><p class="noindent" ><span class="paragraphHead"><a
|
|---|
| 631 | id="x1-270001.3.2"></a><span
|
|---|
| 632 | class="cmbx-12">floor decode</span></span>
|
|---|
| 633 | Each floor is encoded/decoded in channel order, however each floor belongs to a ’submap’ that
|
|---|
| 634 | specifies which floor configuration to use. All floors are decoded before residue decode
|
|---|
| 635 | begins.
|
|---|
| 636 | <!--l. 394--><p class="noindent" ><span class="paragraphHead"><a
|
|---|
| 637 | id="x1-280001.3.2"></a><span
|
|---|
| 638 | class="cmbx-12">residue decode</span></span>
|
|---|
| 639 | Although the number of residue vectors equals the number of channels, channel coupling may
|
|---|
| 640 | mean that the raw residue vectors extracted during decode do not map directly to specific
|
|---|
| 641 | channels. When channel coupling is in use, some vectors will correspond to coupled magnitude or
|
|---|
| 642 | angle. The coupling relationships are described in the codec setup and may differ from frame to
|
|---|
| 643 | frame, due to different mode numbers.
|
|---|
| 644 | <!--l. 403--><p class="noindent" >Vorbis codes residue vectors in groups by submap; the coding is done in submap order from
|
|---|
| 645 | submap 0 through n-1. This differs from floors which are coded using a configuration provided by
|
|---|
| 646 | submap number, but are coded individually in channel order.
|
|---|
| 647 | <!--l. 410--><p class="noindent" ><span class="paragraphHead"><a
|
|---|
| 648 | id="x1-290001.3.2"></a><span
|
|---|
| 649 | class="cmbx-12">inverse channel coupling</span></span>
|
|---|
| 650 | A detailed discussion of stereo in the Vorbis codec can be found in the document
|
|---|
| 651 | <a
|
|---|
| 652 | href="stereo.html" >Stereo Channel Coupling in the Vorbis CODEC</a>. Vorbis is not limited to only stereo
|
|---|
| 653 | coupling, but the stereo document also gives a good overview of the generic coupling
|
|---|
| 654 | mechanism.
|
|---|
| 655 | <!--l. 418--><p class="noindent" >Vorbis coupling applies to pairs of residue vectors at a time; decoupling is done in-place a
|
|---|
| 656 | pair at a time in the order and using the vectors specified in the current mapping
|
|---|
| 657 | configuration. The decoupling operation is the same for all pairs, converting square polar
|
|---|
| 658 | representation (where one vector is magnitude and the second angle) back to Cartesian
|
|---|
| 659 | representation.
|
|---|
| 660 | <!--l. 425--><p class="noindent" >After decoupling, in order, each pair of vectors on the coupling list, the resulting residue vectors
|
|---|
| 661 | represent the fine spectral detail of each output channel.
|
|---|
| 662 |
|
|---|
| 663 |
|
|---|
| 664 |
|
|---|
| 665 | <!--l. 431--><p class="noindent" ><span class="paragraphHead"><a
|
|---|
| 666 | id="x1-300001.3.2"></a><span
|
|---|
| 667 | class="cmbx-12">generate floor curve</span></span>
|
|---|
| 668 | The decoder may choose to generate the floor curve at any appropriate time. It is reasonable to
|
|---|
| 669 | generate the output curve when the floor data is decoded from the raw packet, or it
|
|---|
| 670 | can be generated after inverse coupling and applied to the spectral residue directly,
|
|---|
| 671 | combining generation and the dot product into one step and eliminating some working
|
|---|
| 672 | space.
|
|---|
| 673 | <!--l. 440--><p class="noindent" >Both floor 0 and floor 1 generate a linear-range, linear-domain output vector to be multiplied
|
|---|
| 674 | (dot product) by the linear-range, linear-domain spectral residue.
|
|---|
| 675 | <!--l. 446--><p class="noindent" ><span class="paragraphHead"><a
|
|---|
| 676 | id="x1-310001.3.2"></a><span
|
|---|
| 677 | class="cmbx-12">compute floor/residue dot product</span></span>
|
|---|
| 678 | This step is straightforward; for each output channel, the decoder multiplies the floor curve and
|
|---|
| 679 | residue vectors element by element, producing the finished audio spectrum of each
|
|---|
| 680 | channel.
|
|---|
| 681 | <!--l. 454--><p class="noindent" >One point is worth mentioning about this dot product; a common mistake in a fixed point
|
|---|
| 682 | implementation might be to assume that a 32 bit fixed-point representation for floor and
|
|---|
| 683 | residue and direct multiplication of the vectors is sufficient for acceptable spectral depth
|
|---|
| 684 | in all cases because it happens to mostly work with the current Xiph.Org reference
|
|---|
| 685 | encoder.
|
|---|
| 686 | <!--l. 461--><p class="noindent" >However, floor vector values can span <span
|
|---|
| 687 | class="cmsy-10x-x-120">~</span>140dB (<span
|
|---|
| 688 | class="cmsy-10x-x-120">~</span>24 bits unsigned), and the audio spectrum
|
|---|
| 689 | vector should represent a minimum of 120dB (<span
|
|---|
| 690 | class="cmsy-10x-x-120">~</span>21 bits with sign), even when output is to a 16
|
|---|
| 691 | bit PCM device. For the residue vector to represent full scale if the floor is nailed
|
|---|
| 692 | to <span
|
|---|
| 693 | class="cmsy-10x-x-120">-</span>140dB, it must be able to span 0 to +140dB. For the residue vector to reach
|
|---|
| 694 | full scale if the floor is nailed at 0dB, it must be able to represent <span
|
|---|
| 695 | class="cmsy-10x-x-120">-</span>140dB to +0dB.
|
|---|
| 696 | Thus, in order to handle full range dynamics, a residue vector may span <span
|
|---|
| 697 | class="cmsy-10x-x-120">-</span>140dB to
|
|---|
| 698 | +140dB entirely within spec. A 280dB range is approximately 48 bits with sign; thus the
|
|---|
| 699 | residue vector must be able to represent a 48 bit range and the dot product must
|
|---|
| 700 | be able to handle an effective 48 bit times 24 bit multiplication. This range may be
|
|---|
| 701 | achieved using large (64 bit or larger) integers, or implementing a movable binary point
|
|---|
| 702 | representation.
|
|---|
| 703 | <!--l. 478--><p class="noindent" ><span class="paragraphHead"><a
|
|---|
| 704 | id="x1-320001.3.2"></a><span
|
|---|
| 705 | class="cmbx-12">inverse monolithic transform (MDCT)</span></span>
|
|---|
| 706 | The audio spectrum is converted back into time domain PCM audio via an inverse Modified
|
|---|
| 707 | Discrete Cosine Transform (MDCT). A detailed description of the MDCT is available in
|
|---|
| 708 | <span class="cite">[<a
|
|---|
| 709 | href="#XSporer/Brandenburg/Edler">1</a>]</span>.
|
|---|
| 710 | <!--l. 484--><p class="noindent" >Note that the PCM produced directly from the MDCT is not yet finished audio; it must be
|
|---|
| 711 |
|
|---|
| 712 |
|
|---|
| 713 |
|
|---|
| 714 | lapped with surrounding frames using an appropriate window (such as the Vorbis window) before
|
|---|
| 715 | the MDCT can be considered orthogonal.
|
|---|
| 716 | <!--l. 491--><p class="noindent" ><span class="paragraphHead"><a
|
|---|
| 717 | id="x1-330001.3.2"></a><span
|
|---|
| 718 | class="cmbx-12">overlap/add data</span></span>
|
|---|
| 719 | Windowed MDCT output is overlapped and added with the right hand data of the previous
|
|---|
| 720 | window such that the 3/4 point of the previous window is aligned with the 1/4 point of the
|
|---|
| 721 | current window (as illustrated in the window overlap diagram). At this point, the audio data
|
|---|
| 722 | between the center of the previous frame and the center of the current frame is now finished and
|
|---|
| 723 | ready to be returned.
|
|---|
| 724 | <!--l. 500--><p class="noindent" ><span class="paragraphHead"><a
|
|---|
| 725 | id="x1-340001.3.2"></a><span
|
|---|
| 726 | class="cmbx-12">cache right hand data</span></span>
|
|---|
| 727 | The decoder must cache the right hand portion of the current frame to be lapped with the left
|
|---|
| 728 | hand portion of the next frame.
|
|---|
| 729 | <!--l. 506--><p class="noindent" ><span class="paragraphHead"><a
|
|---|
| 730 | id="x1-350001.3.2"></a><span
|
|---|
| 731 | class="cmbx-12">return finished audio data</span></span>
|
|---|
| 732 | The overlapped portion produced from overlapping the previous and current frame data
|
|---|
| 733 | is finished data to be returned by the decoder. This data spans from the center of
|
|---|
| 734 | the previous window to the center of the current window. In the case of same-sized
|
|---|
| 735 | windows, the amount of data to return is one-half block consisting of and only of the
|
|---|
| 736 | overlapped portions. When overlapping a short and long window, much of the returned
|
|---|
| 737 | range is not actually overlap. This does not damage transform orthogonality. Pay
|
|---|
| 738 | attention however to returning the correct data range; the amount of data to be returned
|
|---|
| 739 | is:
|
|---|
| 740 | <!--l. 518--><p class="noindent" >
|
|---|
| 741 | <div class="fancyvrb" id="fancyvrb1"><a
|
|---|
| 742 | id="x1-35002r1"></a><span
|
|---|
| 743 | class="cmr-6">1</span><span
|
|---|
| 744 | class="cmtt-8">window</span><span
|
|---|
| 745 | class="cmtt-8">_blocksize(previous</span><span
|
|---|
| 746 | class="cmtt-8">_window)/4+window</span><span
|
|---|
| 747 | class="cmtt-8">_blocksize(current</span><span
|
|---|
| 748 | class="cmtt-8">_window)/4</span></div>
|
|---|
| 749 | <!--l. 522--><p class="noindent" >from the center of the previous window to the center of the current window.
|
|---|
| 750 | <!--l. 525--><p class="noindent" >Data is not returned from the first frame; it must be used to ’prime’ the decode engine. The
|
|---|
| 751 | encoder accounts for this priming when calculating PCM offsets; after the first frame, the proper
|
|---|
| 752 | PCM output offset is ’0’ (as no data has been returned yet).
|
|---|
| 753 |
|
|---|
| 754 |
|
|---|
| 755 |
|
|---|
| 756 |
|
|---|
| 757 |
|
|---|
| 758 |
|
|---|
| 759 | <h3 class="sectionHead"><span class="titlemark">2. </span> <a
|
|---|
| 760 | id="x1-360002"></a>Bitpacking Convention</h3>
|
|---|
| 761 | <!--l. 5--><p class="noindent" >
|
|---|
| 762 | <h4 class="subsectionHead"><span class="titlemark">2.1. </span> <a
|
|---|
| 763 | id="x1-370002.1"></a>Overview</h4>
|
|---|
| 764 | <!--l. 7--><p class="noindent" >The Vorbis codec uses relatively unstructured raw packets containing arbitrary-width binary
|
|---|
| 765 | integer fields. Logically, these packets are a bitstream in which bits are coded one-by-one by the
|
|---|
| 766 | encoder and then read one-by-one in the same monotonically increasing order by the decoder.
|
|---|
| 767 | Most current binary storage arrangements group bits into a native word size of eight bits
|
|---|
| 768 | (octets), sixteen bits, thirty-two bits or, less commonly other fixed word sizes. The Vorbis
|
|---|
| 769 | bitpacking convention specifies the correct mapping of the logical packet bitstream into an actual
|
|---|
| 770 | representation in fixed-width words.
|
|---|
| 771 | <!--l. 18--><p class="noindent" >
|
|---|
| 772 | <h5 class="subsubsectionHead"><span class="titlemark">2.1.1. </span> <a
|
|---|
| 773 | id="x1-380002.1.1"></a>octets, bytes and words</h5>
|
|---|
| 774 | <!--l. 20--><p class="noindent" >In most contemporary architectures, a ’byte’ is synonymous with an ’octet’, that is, eight bits.
|
|---|
| 775 | This has not always been the case; seven, ten, eleven and sixteen bit ’bytes’ have been used.
|
|---|
| 776 | For purposes of the bitpacking convention, a byte implies the native, smallest integer
|
|---|
| 777 | storage representation offered by a platform. On modern platforms, this is generally
|
|---|
| 778 | assumed to be eight bits (not necessarily because of the processor but because of the
|
|---|
| 779 | filesystem/memory architecture. Modern filesystems invariably offer bytes as the fundamental
|
|---|
| 780 | atom of storage). A ’word’ is an integer size that is a grouped multiple of this smallest
|
|---|
| 781 | size.
|
|---|
| 782 | <!--l. 31--><p class="noindent" >The most ubiquitous architectures today consider a ’byte’ to be an octet (eight bits) and a word
|
|---|
| 783 | to be a group of two, four or eight bytes (16, 32 or 64 bits). Note however that the Vorbis
|
|---|
| 784 | bitpacking convention is still well defined for any native byte size; Vorbis uses the native
|
|---|
| 785 | bit-width of a given storage system. This document assumes that a byte is one octet for purposes
|
|---|
| 786 | of example.
|
|---|
| 787 | <!--l. 38--><p class="noindent" >
|
|---|
| 788 |
|
|---|
| 789 |
|
|---|
| 790 |
|
|---|
| 791 | <h5 class="subsubsectionHead"><span class="titlemark">2.1.2. </span> <a
|
|---|
| 792 | id="x1-390002.1.2"></a>bit order</h5>
|
|---|
| 793 | <!--l. 40--><p class="noindent" >A byte has a well-defined ’least significant’ bit (LSb), which is the only bit set when the byte is
|
|---|
| 794 | storing the two’s complement integer value +1. A byte’s ’most significant’ bit (MSb) is at the
|
|---|
| 795 | opposite end of the byte. Bits in a byte are numbered from zero at the LSb to <span
|
|---|
| 796 | class="cmmi-12">n </span>(<span
|
|---|
| 797 | class="cmmi-12">n </span>= 7 in an
|
|---|
| 798 | octet) for the MSb.
|
|---|
| 799 | <!--l. 49--><p class="noindent" >
|
|---|
| 800 | <h5 class="subsubsectionHead"><span class="titlemark">2.1.3. </span> <a
|
|---|
| 801 | id="x1-400002.1.3"></a>byte order</h5>
|
|---|
| 802 | <!--l. 51--><p class="noindent" >Words are native groupings of multiple bytes. Several byte orderings are possible in a word; the
|
|---|
| 803 | common ones are 3-2-1-0 (’big endian’ or ’most significant byte first’ in which the
|
|---|
| 804 | highest-valued byte comes first), 0-1-2-3 (’little endian’ or ’least significant byte first’ in
|
|---|
| 805 | which the lowest value byte comes first) and less commonly 3-1-2-0 and 0-2-1-3 (’mixed
|
|---|
| 806 | endian’).
|
|---|
| 807 | <!--l. 58--><p class="noindent" >The Vorbis bitpacking convention specifies storage and bitstream manipulation at the byte, not
|
|---|
| 808 | word, level, thus host word ordering is of a concern only during optimization when writing high
|
|---|
| 809 | performance code that operates on a word of storage at a time rather than by byte.
|
|---|
| 810 | Logically, bytes are always coded and decoded in order from byte zero through byte
|
|---|
| 811 | <span
|
|---|
| 812 | class="cmmi-12">n</span>.
|
|---|
| 813 | <!--l. 67--><p class="noindent" >
|
|---|
| 814 | <h5 class="subsubsectionHead"><span class="titlemark">2.1.4. </span> <a
|
|---|
| 815 | id="x1-410002.1.4"></a>coding bits into byte sequences</h5>
|
|---|
| 816 | <!--l. 69--><p class="noindent" >The Vorbis codec has need to code arbitrary bit-width integers, from zero to 32 bits
|
|---|
| 817 | wide, into packets. These integer fields are not aligned to the boundaries of the byte
|
|---|
| 818 | representation; the next field is written at the bit position at which the previous field
|
|---|
| 819 | ends.
|
|---|
| 820 | <!--l. 74--><p class="noindent" >The encoder logically packs integers by writing the LSb of a binary integer to the logical
|
|---|
| 821 | bitstream first, followed by next least significant bit, etc, until the requested number of bits
|
|---|
| 822 | have been coded. When packing the bits into bytes, the encoder begins by placing
|
|---|
| 823 | the LSb of the integer to be written into the least significant unused bit position of
|
|---|
| 824 | the destination byte, followed by the next-least significant bit of the source integer
|
|---|
| 825 | and so on up to the requested number of bits. When all bits of the destination byte
|
|---|
| 826 | have been filled, encoding continues by zeroing all bits of the next byte and writing
|
|---|
| 827 | the next bit into the bit position 0 of that byte. Decoding follows the same process
|
|---|
| 828 |
|
|---|
| 829 |
|
|---|
| 830 |
|
|---|
| 831 | as encoding, but by reading bits from the byte stream and reassembling them into
|
|---|
| 832 | integers.
|
|---|
| 833 | <!--l. 89--><p class="noindent" >
|
|---|
| 834 | <h5 class="subsubsectionHead"><span class="titlemark">2.1.5. </span> <a
|
|---|
| 835 | id="x1-420002.1.5"></a>signedness</h5>
|
|---|
| 836 | <!--l. 91--><p class="noindent" >The signedness of a specific number resulting from decode is to be interpreted by the decoder
|
|---|
| 837 | given decode context. That is, the three bit binary pattern ’b111’ can be taken to represent
|
|---|
| 838 | either ’seven’ as an unsigned integer, or ’-1’ as a signed, two’s complement integer. The
|
|---|
| 839 | encoder and decoder are responsible for knowing if fields are to be treated as signed or
|
|---|
| 840 | unsigned.
|
|---|
| 841 | <!--l. 100--><p class="noindent" >
|
|---|
| 842 | <h5 class="subsubsectionHead"><span class="titlemark">2.1.6. </span> <a
|
|---|
| 843 | id="x1-430002.1.6"></a>coding example</h5>
|
|---|
| 844 | <!--l. 102--><p class="noindent" >Code the 4 bit integer value ’12’ [b1100] into an empty bytestream. Bytestream result:
|
|---|
| 845 | <!--l. 105--><p class="noindent" >
|
|---|
| 846 | <div class="fancyvrb" id="fancyvrb2"><a
|
|---|
| 847 | id="x1-43002r1"></a><span
|
|---|
| 848 | class="cmr-6">1</span><span
|
|---|
| 849 | class="cmtt-8"> </span><span
|
|---|
| 850 | class="cmtt-8"> </span><span
|
|---|
| 851 | class="cmtt-8"> </span><span
|
|---|
| 852 | class="cmtt-8"> </span><span
|
|---|
| 853 | class="cmtt-8"> </span><span
|
|---|
| 854 | class="cmtt-8"> </span><span
|
|---|
| 855 | class="cmtt-8"> </span><span
|
|---|
| 856 | class="cmtt-8"> </span><span
|
|---|
| 857 | class="cmtt-8"> </span><span
|
|---|
| 858 | class="cmtt-8"> </span><span
|
|---|
| 859 | class="cmtt-8"> </span><span
|
|---|
| 860 | class="cmtt-8"> </span><span
|
|---|
| 861 | class="cmtt-8"> </span><span
|
|---|
| 862 | class="cmtt-8"> |</span><br class="fancyvrb" /><a
|
|---|
| 863 | id="x1-43004r2"></a><span
|
|---|
| 864 | class="cmr-6">2</span><span
|
|---|
| 865 | class="cmtt-8"> </span><span
|
|---|
| 866 | class="cmtt-8"> </span><span
|
|---|
| 867 | class="cmtt-8"> </span><span
|
|---|
| 868 | class="cmtt-8"> </span><span
|
|---|
| 869 | class="cmtt-8"> </span><span
|
|---|
| 870 | class="cmtt-8"> </span><span
|
|---|
| 871 | class="cmtt-8"> </span><span
|
|---|
| 872 | class="cmtt-8"> </span><span
|
|---|
| 873 | class="cmtt-8"> </span><span
|
|---|
| 874 | class="cmtt-8"> </span><span
|
|---|
| 875 | class="cmtt-8"> </span><span
|
|---|
| 876 | class="cmtt-8"> </span><span
|
|---|
| 877 | class="cmtt-8"> </span><span
|
|---|
| 878 | class="cmtt-8"> V</span><br class="fancyvrb" /><a
|
|---|
| 879 | id="x1-43006r3"></a><span
|
|---|
| 880 | class="cmr-6">3</span><br class="fancyvrb" /><a
|
|---|
| 881 | id="x1-43008r4"></a><span
|
|---|
| 882 | class="cmr-6">4</span><span
|
|---|
| 883 | class="cmtt-8"> </span><span
|
|---|
| 884 | class="cmtt-8"> </span><span
|
|---|
| 885 | class="cmtt-8"> </span><span
|
|---|
| 886 | class="cmtt-8"> </span><span
|
|---|
| 887 | class="cmtt-8"> </span><span
|
|---|
| 888 | class="cmtt-8"> </span><span
|
|---|
| 889 | class="cmtt-8"> </span><span
|
|---|
| 890 | class="cmtt-8"> 7</span><span
|
|---|
| 891 | class="cmtt-8"> 6</span><span
|
|---|
| 892 | class="cmtt-8"> 5</span><span
|
|---|
| 893 | class="cmtt-8"> 4</span><span
|
|---|
| 894 | class="cmtt-8"> 3</span><span
|
|---|
| 895 | class="cmtt-8"> 2</span><span
|
|---|
| 896 | class="cmtt-8"> 1</span><span
|
|---|
| 897 | class="cmtt-8"> 0</span><br class="fancyvrb" /><a
|
|---|
| 898 | id="x1-43010r5"></a><span
|
|---|
| 899 | class="cmr-6">5</span><span
|
|---|
| 900 | class="cmtt-8">byte</span><span
|
|---|
| 901 | class="cmtt-8"> 0</span><span
|
|---|
| 902 | class="cmtt-8"> [0</span><span
|
|---|
| 903 | class="cmtt-8"> 0</span><span
|
|---|
| 904 | class="cmtt-8"> 0</span><span
|
|---|
| 905 | class="cmtt-8"> 0</span><span
|
|---|
| 906 | class="cmtt-8"> 1</span><span
|
|---|
| 907 | class="cmtt-8"> 1</span><span
|
|---|
| 908 | class="cmtt-8"> 0</span><span
|
|---|
| 909 | class="cmtt-8"> 0]</span><span
|
|---|
| 910 | class="cmtt-8"> </span><span
|
|---|
| 911 | class="cmtt-8"> <-</span><br class="fancyvrb" /><a
|
|---|
| 912 | id="x1-43012r6"></a><span
|
|---|
| 913 | class="cmr-6">6</span><span
|
|---|
| 914 | class="cmtt-8">byte</span><span
|
|---|
| 915 | class="cmtt-8"> 1</span><span
|
|---|
| 916 | class="cmtt-8"> [</span><span
|
|---|
| 917 | class="cmtt-8"> </span><span
|
|---|
| 918 | class="cmtt-8"> </span><span
|
|---|
| 919 | class="cmtt-8"> </span><span
|
|---|
| 920 | class="cmtt-8"> </span><span
|
|---|
| 921 | class="cmtt-8"> </span><span
|
|---|
| 922 | class="cmtt-8"> </span><span
|
|---|
| 923 | class="cmtt-8"> </span><span
|
|---|
| 924 | class="cmtt-8"> </span><span
|
|---|
| 925 | class="cmtt-8"> </span><span
|
|---|
| 926 | class="cmtt-8"> </span><span
|
|---|
| 927 | class="cmtt-8"> </span><span
|
|---|
| 928 | class="cmtt-8"> </span><span
|
|---|
| 929 | class="cmtt-8"> </span><span
|
|---|
| 930 | class="cmtt-8"> </span><span
|
|---|
| 931 | class="cmtt-8"> ]</span>
|
|---|
| 932 | <br class="fancyvrb" /><a
|
|---|
| 933 | id="x1-43014r7"></a><span
|
|---|
| 934 | class="cmr-6">7</span><span
|
|---|
| 935 | class="cmtt-8">byte</span><span
|
|---|
| 936 | class="cmtt-8"> 2</span><span
|
|---|
| 937 | class="cmtt-8"> [</span><span
|
|---|
| 938 | class="cmtt-8"> </span><span
|
|---|
| 939 | class="cmtt-8"> </span><span
|
|---|
| 940 | class="cmtt-8"> </span><span
|
|---|
| 941 | class="cmtt-8"> </span><span
|
|---|
| 942 | class="cmtt-8"> </span><span
|
|---|
| 943 | class="cmtt-8"> </span><span
|
|---|
| 944 | class="cmtt-8"> </span><span
|
|---|
| 945 | class="cmtt-8"> </span><span
|
|---|
| 946 | class="cmtt-8"> </span><span
|
|---|
| 947 | class="cmtt-8"> </span><span
|
|---|
| 948 | class="cmtt-8"> </span><span
|
|---|
| 949 | class="cmtt-8"> </span><span
|
|---|
| 950 | class="cmtt-8"> </span><span
|
|---|
| 951 | class="cmtt-8"> </span><span
|
|---|
| 952 | class="cmtt-8"> ]</span><br class="fancyvrb" /><a
|
|---|
| 953 | id="x1-43016r8"></a><span
|
|---|
| 954 | class="cmr-6">8</span><span
|
|---|
| 955 | class="cmtt-8">byte</span><span
|
|---|
| 956 | class="cmtt-8"> 3</span><span
|
|---|
| 957 | class="cmtt-8"> [</span><span
|
|---|
| 958 | class="cmtt-8"> </span><span
|
|---|
| 959 | class="cmtt-8"> </span><span
|
|---|
| 960 | class="cmtt-8"> </span><span
|
|---|
| 961 | class="cmtt-8"> </span><span
|
|---|
| 962 | class="cmtt-8"> </span><span
|
|---|
| 963 | class="cmtt-8"> </span><span
|
|---|
| 964 | class="cmtt-8"> </span><span
|
|---|
| 965 | class="cmtt-8"> </span><span
|
|---|
| 966 | class="cmtt-8"> </span><span
|
|---|
| 967 | class="cmtt-8"> </span><span
|
|---|
| 968 | class="cmtt-8"> </span><span
|
|---|
| 969 | class="cmtt-8"> </span><span
|
|---|
| 970 | class="cmtt-8"> </span><span
|
|---|
| 971 | class="cmtt-8"> </span><span
|
|---|
| 972 | class="cmtt-8"> ]</span><br class="fancyvrb" /><a
|
|---|
| 973 | id="x1-43018r9"></a><span
|
|---|
| 974 | class="cmr-6">9</span><span
|
|---|
| 975 | class="cmtt-8"> </span><span
|
|---|
| 976 | class="cmtt-8"> </span><span
|
|---|
| 977 | class="cmtt-8"> </span><span
|
|---|
| 978 | class="cmtt-8"> </span><span
|
|---|
| 979 | class="cmtt-8"> </span><span
|
|---|
| 980 | class="cmtt-8"> </span><span
|
|---|
| 981 | class="cmtt-8"> </span><span
|
|---|
| 982 | class="cmtt-8"> </span><span
|
|---|
| 983 | class="cmtt-8"> </span><span
|
|---|
| 984 | class="cmtt-8"> </span><span
|
|---|
| 985 | class="cmtt-8"> </span><span
|
|---|
| 986 | class="cmtt-8"> </span><span
|
|---|
| 987 | class="cmtt-8"> ...</span><br class="fancyvrb" /><a
|
|---|
| 988 | id="x1-43020r10"></a><span
|
|---|
| 989 | class="cmr-6">10</span><span
|
|---|
| 990 | class="cmtt-8">byte</span><span
|
|---|
| 991 | class="cmtt-8"> n</span><span
|
|---|
| 992 | class="cmtt-8"> [</span><span
|
|---|
| 993 | class="cmtt-8"> </span><span
|
|---|
| 994 | class="cmtt-8"> </span><span
|
|---|
| 995 | class="cmtt-8"> </span><span
|
|---|
| 996 | class="cmtt-8"> </span><span
|
|---|
| 997 | class="cmtt-8"> </span><span
|
|---|
| 998 | class="cmtt-8"> </span><span
|
|---|
| 999 | class="cmtt-8"> </span><span
|
|---|
| 1000 | class="cmtt-8"> </span><span
|
|---|
| 1001 | class="cmtt-8"> </span><span
|
|---|
| 1002 | class="cmtt-8"> </span><span
|
|---|
| 1003 | class="cmtt-8"> </span><span
|
|---|
| 1004 | class="cmtt-8"> </span><span
|
|---|
| 1005 | class="cmtt-8"> </span><span
|
|---|
| 1006 | class="cmtt-8"> </span><span
|
|---|
| 1007 | class="cmtt-8"> ]</span><span
|
|---|
| 1008 | class="cmtt-8"> </span><span
|
|---|
| 1009 | class="cmtt-8"> bytestream</span><span
|
|---|
| 1010 | class="cmtt-8"> length</span><span
|
|---|
| 1011 | class="cmtt-8"> ==</span><span
|
|---|
| 1012 | class="cmtt-8"> 1</span><span
|
|---|
| 1013 | class="cmtt-8"> byte</span><br class="fancyvrb" /><a
|
|---|
| 1014 | id="x1-43022r11"></a><span
|
|---|
| 1015 | class="cmr-6">11</span></div>
|
|---|
| 1016 | <!--l. 120--><p class="noindent" >Continue by coding the 3 bit integer value ’-1’ [b111]:
|
|---|
| 1017 | <!--l. 122--><p class="noindent" >
|
|---|
| 1018 | <div class="fancyvrb" id="fancyvrb3"><a
|
|---|
| 1019 | id="x1-43024r1"></a><span
|
|---|
| 1020 | class="cmr-6">1</span><span
|
|---|
| 1021 | class="cmtt-8"> </span><span
|
|---|
| 1022 | class="cmtt-8"> </span><span
|
|---|
| 1023 | class="cmtt-8"> </span><span
|
|---|
| 1024 | class="cmtt-8"> </span><span
|
|---|
| 1025 | class="cmtt-8"> </span><span
|
|---|
| 1026 | class="cmtt-8"> </span><span
|
|---|
| 1027 | class="cmtt-8"> </span><span
|
|---|
| 1028 | class="cmtt-8"> |</span><br class="fancyvrb" /><a
|
|---|
| 1029 | id="x1-43026r2"></a><span
|
|---|
| 1030 | class="cmr-6">2</span><span
|
|---|
| 1031 | class="cmtt-8"> </span><span
|
|---|
| 1032 | class="cmtt-8"> </span><span
|
|---|
| 1033 | class="cmtt-8"> </span><span
|
|---|
| 1034 | class="cmtt-8"> </span><span
|
|---|
| 1035 | class="cmtt-8"> </span><span
|
|---|
| 1036 | class="cmtt-8"> </span><span
|
|---|
| 1037 | class="cmtt-8"> </span><span
|
|---|
| 1038 | class="cmtt-8"> V</span><br class="fancyvrb" /><a
|
|---|
| 1039 | id="x1-43028r3"></a><span
|
|---|
| 1040 | class="cmr-6">3</span><br class="fancyvrb" /><a
|
|---|
| 1041 | id="x1-43030r4"></a><span
|
|---|
| 1042 | class="cmr-6">4</span><span
|
|---|
| 1043 | class="cmtt-8"> </span><span
|
|---|
| 1044 | class="cmtt-8"> </span><span
|
|---|
| 1045 | class="cmtt-8"> </span><span
|
|---|
| 1046 | class="cmtt-8"> </span><span
|
|---|
| 1047 | class="cmtt-8"> </span><span
|
|---|
| 1048 | class="cmtt-8"> </span><span
|
|---|
| 1049 | class="cmtt-8"> </span><span
|
|---|
| 1050 | class="cmtt-8"> 7</span><span
|
|---|
| 1051 | class="cmtt-8"> 6</span><span
|
|---|
| 1052 | class="cmtt-8"> 5</span><span
|
|---|
| 1053 | class="cmtt-8"> 4</span><span
|
|---|
| 1054 | class="cmtt-8"> 3</span><span
|
|---|
| 1055 | class="cmtt-8"> 2</span><span
|
|---|
| 1056 | class="cmtt-8"> 1</span><span
|
|---|
| 1057 | class="cmtt-8"> 0</span><br class="fancyvrb" /><a
|
|---|
| 1058 | id="x1-43032r5"></a><span
|
|---|
| 1059 | class="cmr-6">5</span><span
|
|---|
| 1060 | class="cmtt-8">byte</span><span
|
|---|
| 1061 | class="cmtt-8"> 0</span><span
|
|---|
| 1062 | class="cmtt-8"> [0</span><span
|
|---|
| 1063 | class="cmtt-8"> 1</span><span
|
|---|
| 1064 | class="cmtt-8"> 1</span><span
|
|---|
| 1065 | class="cmtt-8"> 1</span><span
|
|---|
| 1066 | class="cmtt-8"> 1</span><span
|
|---|
| 1067 | class="cmtt-8"> 1</span><span
|
|---|
| 1068 | class="cmtt-8"> 0</span><span
|
|---|
| 1069 | class="cmtt-8"> 0]</span><span
|
|---|
| 1070 | class="cmtt-8"> </span><span
|
|---|
| 1071 | class="cmtt-8"> <-</span><br class="fancyvrb" /><a
|
|---|
| 1072 | id="x1-43034r6"></a><span
|
|---|
| 1073 | class="cmr-6">6</span><span
|
|---|
| 1074 | class="cmtt-8">byte</span><span
|
|---|
| 1075 | class="cmtt-8"> 1</span><span
|
|---|
| 1076 | class="cmtt-8"> [</span><span
|
|---|
| 1077 | class="cmtt-8"> </span><span
|
|---|
| 1078 | class="cmtt-8"> </span><span
|
|---|
| 1079 | class="cmtt-8"> </span><span
|
|---|
| 1080 | class="cmtt-8"> </span><span
|
|---|
| 1081 | class="cmtt-8"> </span><span
|
|---|
| 1082 | class="cmtt-8"> </span><span
|
|---|
| 1083 | class="cmtt-8"> </span><span
|
|---|
| 1084 | class="cmtt-8"> </span><span
|
|---|
| 1085 | class="cmtt-8"> </span><span
|
|---|
| 1086 | class="cmtt-8"> </span><span
|
|---|
| 1087 | class="cmtt-8"> </span><span
|
|---|
| 1088 | class="cmtt-8"> </span><span
|
|---|
| 1089 | class="cmtt-8"> </span><span
|
|---|
| 1090 | class="cmtt-8"> </span><span
|
|---|
| 1091 | class="cmtt-8"> ]</span><br class="fancyvrb" /><a
|
|---|
| 1092 | id="x1-43036r7"></a><span
|
|---|
| 1093 | class="cmr-6">7</span><span
|
|---|
| 1094 | class="cmtt-8">byte</span><span
|
|---|
| 1095 | class="cmtt-8"> 2</span><span
|
|---|
| 1096 | class="cmtt-8"> [</span><span
|
|---|
| 1097 | class="cmtt-8"> </span><span
|
|---|
| 1098 | class="cmtt-8"> </span><span
|
|---|
| 1099 | class="cmtt-8"> </span><span
|
|---|
| 1100 | class="cmtt-8"> </span><span
|
|---|
| 1101 | class="cmtt-8"> </span><span
|
|---|
| 1102 | class="cmtt-8"> </span><span
|
|---|
| 1103 | class="cmtt-8"> </span><span
|
|---|
| 1104 | class="cmtt-8"> </span><span
|
|---|
| 1105 | class="cmtt-8"> </span><span
|
|---|
| 1106 | class="cmtt-8"> </span><span
|
|---|
| 1107 | class="cmtt-8"> </span><span
|
|---|
| 1108 | class="cmtt-8"> </span><span
|
|---|
| 1109 | class="cmtt-8"> </span><span
|
|---|
| 1110 | class="cmtt-8"> </span><span
|
|---|
| 1111 | class="cmtt-8"> ]</span>
|
|---|
| 1112 | <br class="fancyvrb" /><a
|
|---|
| 1113 | id="x1-43038r8"></a><span
|
|---|
| 1114 | class="cmr-6">8</span><span
|
|---|
| 1115 | class="cmtt-8">byte</span><span
|
|---|
| 1116 | class="cmtt-8"> 3</span><span
|
|---|
| 1117 | class="cmtt-8"> [</span><span
|
|---|
| 1118 | class="cmtt-8"> </span><span
|
|---|
| 1119 | class="cmtt-8"> </span><span
|
|---|
| 1120 | class="cmtt-8"> </span><span
|
|---|
| 1121 | class="cmtt-8"> </span><span
|
|---|
| 1122 | class="cmtt-8"> </span><span
|
|---|
| 1123 | class="cmtt-8"> </span><span
|
|---|
| 1124 | class="cmtt-8"> </span><span
|
|---|
| 1125 | class="cmtt-8"> </span><span
|
|---|
| 1126 | class="cmtt-8"> </span><span
|
|---|
| 1127 | class="cmtt-8"> </span><span
|
|---|
| 1128 | class="cmtt-8"> </span><span
|
|---|
| 1129 | class="cmtt-8"> </span><span
|
|---|
| 1130 | class="cmtt-8"> </span><span
|
|---|
| 1131 | class="cmtt-8"> </span><span
|
|---|
| 1132 | class="cmtt-8"> ]</span><br class="fancyvrb" /><a
|
|---|
| 1133 | id="x1-43040r9"></a><span
|
|---|
| 1134 | class="cmr-6">9</span><span
|
|---|
| 1135 | class="cmtt-8"> </span><span
|
|---|
| 1136 | class="cmtt-8"> </span><span
|
|---|
| 1137 | class="cmtt-8"> </span><span
|
|---|
| 1138 | class="cmtt-8"> </span><span
|
|---|
| 1139 | class="cmtt-8"> </span><span
|
|---|
| 1140 | class="cmtt-8"> </span><span
|
|---|
| 1141 | class="cmtt-8"> </span><span
|
|---|
| 1142 | class="cmtt-8"> </span><span
|
|---|
| 1143 | class="cmtt-8"> </span><span
|
|---|
| 1144 | class="cmtt-8"> </span><span
|
|---|
| 1145 | class="cmtt-8"> </span><span
|
|---|
| 1146 | class="cmtt-8"> </span><span
|
|---|
| 1147 | class="cmtt-8"> ...</span><br class="fancyvrb" /><a
|
|---|
| 1148 | id="x1-43042r10"></a><span
|
|---|
| 1149 | class="cmr-6">10</span><span
|
|---|
| 1150 | class="cmtt-8">byte</span><span
|
|---|
| 1151 | class="cmtt-8"> n</span><span
|
|---|
| 1152 | class="cmtt-8"> [</span><span
|
|---|
| 1153 | class="cmtt-8"> </span><span
|
|---|
| 1154 | class="cmtt-8"> </span><span
|
|---|
| 1155 | class="cmtt-8"> </span><span
|
|---|
| 1156 | class="cmtt-8"> </span><span
|
|---|
| 1157 | class="cmtt-8"> </span><span
|
|---|
| 1158 | class="cmtt-8"> </span><span
|
|---|
| 1159 | class="cmtt-8"> </span><span
|
|---|
| 1160 | class="cmtt-8"> </span><span
|
|---|
| 1161 | class="cmtt-8"> </span><span
|
|---|
| 1162 | class="cmtt-8"> </span><span
|
|---|
| 1163 | class="cmtt-8"> </span><span
|
|---|
| 1164 | class="cmtt-8"> </span><span
|
|---|
| 1165 | class="cmtt-8"> </span><span
|
|---|
| 1166 | class="cmtt-8"> </span><span
|
|---|
| 1167 | class="cmtt-8"> ]</span><span
|
|---|
| 1168 | class="cmtt-8"> </span><span
|
|---|
| 1169 | class="cmtt-8"> bytestream</span><span
|
|---|
| 1170 | class="cmtt-8"> length</span><span
|
|---|
| 1171 | class="cmtt-8"> ==</span><span
|
|---|
| 1172 | class="cmtt-8"> 1</span><span
|
|---|
| 1173 | class="cmtt-8"> byte</span></div>
|
|---|
| 1174 | <!--l. 136--><p class="noindent" >Continue by coding the 7 bit integer value ’17’ [b0010001]:
|
|---|
| 1175 | <!--l. 138--><p class="noindent" >
|
|---|
| 1176 | <div class="fancyvrb" id="fancyvrb4"><a
|
|---|
| 1177 | id="x1-43044r1"></a><span
|
|---|
| 1178 | class="cmr-6">1</span><span
|
|---|
| 1179 | class="cmtt-8"> </span><span
|
|---|
| 1180 | class="cmtt-8"> </span><span
|
|---|
| 1181 | class="cmtt-8"> </span><span
|
|---|
| 1182 | class="cmtt-8"> </span><span
|
|---|
| 1183 | class="cmtt-8"> </span><span
|
|---|
| 1184 | class="cmtt-8"> </span><span
|
|---|
| 1185 | class="cmtt-8"> </span><span
|
|---|
| 1186 | class="cmtt-8"> </span><span
|
|---|
| 1187 | class="cmtt-8"> </span><span
|
|---|
| 1188 | class="cmtt-8"> |</span><br class="fancyvrb" /><a
|
|---|
| 1189 | id="x1-43046r2"></a><span
|
|---|
| 1190 | class="cmr-6">2</span><span
|
|---|
| 1191 | class="cmtt-8"> </span><span
|
|---|
| 1192 | class="cmtt-8"> </span><span
|
|---|
| 1193 | class="cmtt-8"> </span><span
|
|---|
| 1194 | class="cmtt-8"> </span><span
|
|---|
| 1195 | class="cmtt-8"> </span><span
|
|---|
| 1196 | class="cmtt-8"> </span><span
|
|---|
| 1197 | class="cmtt-8"> </span><span
|
|---|
| 1198 | class="cmtt-8"> </span><span
|
|---|
| 1199 | class="cmtt-8"> </span><span
|
|---|
| 1200 | class="cmtt-8"> V</span><br class="fancyvrb" /><a
|
|---|
| 1201 | id="x1-43048r3"></a><span
|
|---|
| 1202 | class="cmr-6">3</span><br class="fancyvrb" /><a
|
|---|
| 1203 | id="x1-43050r4"></a><span
|
|---|
| 1204 | class="cmr-6">4</span><span
|
|---|
| 1205 | class="cmtt-8"> </span><span
|
|---|
| 1206 | class="cmtt-8"> </span><span
|
|---|
| 1207 | class="cmtt-8"> </span><span
|
|---|
| 1208 | class="cmtt-8"> </span><span
|
|---|
| 1209 | class="cmtt-8"> </span><span
|
|---|
| 1210 | class="cmtt-8"> </span><span
|
|---|
| 1211 | class="cmtt-8"> </span><span
|
|---|
| 1212 | class="cmtt-8"> 7</span><span
|
|---|
| 1213 | class="cmtt-8"> 6</span><span
|
|---|
| 1214 | class="cmtt-8"> 5</span><span
|
|---|
| 1215 | class="cmtt-8"> 4</span><span
|
|---|
| 1216 | class="cmtt-8"> 3</span><span
|
|---|
| 1217 | class="cmtt-8"> 2</span><span
|
|---|
| 1218 | class="cmtt-8"> 1</span><span
|
|---|
| 1219 | class="cmtt-8"> 0</span><br class="fancyvrb" /><a
|
|---|
| 1220 | id="x1-43052r5"></a><span
|
|---|
| 1221 | class="cmr-6">5</span><span
|
|---|
| 1222 | class="cmtt-8">byte</span><span
|
|---|
| 1223 | class="cmtt-8"> 0</span><span
|
|---|
| 1224 | class="cmtt-8"> [1</span><span
|
|---|
| 1225 | class="cmtt-8"> 1</span><span
|
|---|
| 1226 | class="cmtt-8"> 1</span><span
|
|---|
| 1227 | class="cmtt-8"> 1</span><span
|
|---|
| 1228 | class="cmtt-8"> 1</span><span
|
|---|
| 1229 | class="cmtt-8"> 1</span><span
|
|---|
| 1230 | class="cmtt-8"> 0</span><span
|
|---|
| 1231 | class="cmtt-8"> 0]</span><br class="fancyvrb" /><a
|
|---|
| 1232 | id="x1-43054r6"></a><span
|
|---|
| 1233 | class="cmr-6">6</span><span
|
|---|
| 1234 | class="cmtt-8">byte</span><span
|
|---|
| 1235 | class="cmtt-8"> 1</span><span
|
|---|
| 1236 | class="cmtt-8"> [0</span><span
|
|---|
| 1237 | class="cmtt-8"> 0</span><span
|
|---|
| 1238 | class="cmtt-8"> 0</span><span
|
|---|
| 1239 | class="cmtt-8"> 0</span><span
|
|---|
| 1240 | class="cmtt-8"> 1</span><span
|
|---|
| 1241 | class="cmtt-8"> 0</span><span
|
|---|
| 1242 | class="cmtt-8"> 0</span><span
|
|---|
| 1243 | class="cmtt-8"> 0]</span><span
|
|---|
| 1244 | class="cmtt-8"> </span><span
|
|---|
| 1245 | class="cmtt-8"> <-</span><br class="fancyvrb" /><a
|
|---|
| 1246 | id="x1-43056r7"></a><span
|
|---|
| 1247 | class="cmr-6">7</span><span
|
|---|
| 1248 | class="cmtt-8">byte</span><span
|
|---|
| 1249 | class="cmtt-8"> 2</span><span
|
|---|
| 1250 | class="cmtt-8"> [</span><span
|
|---|
| 1251 | class="cmtt-8"> </span><span
|
|---|
| 1252 | class="cmtt-8"> </span><span
|
|---|
| 1253 | class="cmtt-8"> </span><span
|
|---|
| 1254 | class="cmtt-8"> </span><span
|
|---|
| 1255 | class="cmtt-8"> </span><span
|
|---|
| 1256 | class="cmtt-8"> </span><span
|
|---|
| 1257 | class="cmtt-8"> </span><span
|
|---|
| 1258 | class="cmtt-8"> </span><span
|
|---|
| 1259 | class="cmtt-8"> </span><span
|
|---|
| 1260 | class="cmtt-8"> </span><span
|
|---|
| 1261 | class="cmtt-8"> </span><span
|
|---|
| 1262 | class="cmtt-8"> </span><span
|
|---|
| 1263 | class="cmtt-8"> </span><span
|
|---|
| 1264 | class="cmtt-8"> </span><span
|
|---|
| 1265 | class="cmtt-8"> ]</span>
|
|---|
| 1266 | <br class="fancyvrb" /><a
|
|---|
| 1267 | id="x1-43058r8"></a><span
|
|---|
| 1268 | class="cmr-6">8</span><span
|
|---|
| 1269 | class="cmtt-8">byte</span><span
|
|---|
| 1270 | class="cmtt-8"> 3</span><span
|
|---|
| 1271 | class="cmtt-8"> [</span><span
|
|---|
| 1272 | class="cmtt-8"> </span><span
|
|---|
| 1273 | class="cmtt-8"> </span><span
|
|---|
| 1274 | class="cmtt-8"> </span><span
|
|---|
| 1275 | class="cmtt-8"> </span><span
|
|---|
| 1276 | class="cmtt-8"> </span><span
|
|---|
| 1277 | class="cmtt-8"> </span><span
|
|---|
| 1278 | class="cmtt-8"> </span><span
|
|---|
| 1279 | class="cmtt-8"> </span><span
|
|---|
| 1280 | class="cmtt-8"> </span><span
|
|---|
| 1281 | class="cmtt-8"> </span><span
|
|---|
| 1282 | class="cmtt-8"> </span><span
|
|---|
| 1283 | class="cmtt-8"> </span><span
|
|---|
| 1284 | class="cmtt-8"> </span><span
|
|---|
| 1285 | class="cmtt-8"> </span><span
|
|---|
| 1286 | class="cmtt-8"> ]</span><br class="fancyvrb" /><a
|
|---|
| 1287 | id="x1-43060r9"></a><span
|
|---|
| 1288 | class="cmr-6">9</span><span
|
|---|
| 1289 | class="cmtt-8"> </span><span
|
|---|
| 1290 | class="cmtt-8"> </span><span
|
|---|
| 1291 | class="cmtt-8"> </span><span
|
|---|
| 1292 | class="cmtt-8"> </span><span
|
|---|
| 1293 | class="cmtt-8"> </span><span
|
|---|
| 1294 | class="cmtt-8"> </span><span
|
|---|
| 1295 | class="cmtt-8"> </span><span
|
|---|
| 1296 | class="cmtt-8"> </span><span
|
|---|
| 1297 | class="cmtt-8"> </span><span
|
|---|
| 1298 | class="cmtt-8"> </span><span
|
|---|
| 1299 | class="cmtt-8"> </span><span
|
|---|
| 1300 | class="cmtt-8"> </span><span
|
|---|
| 1301 | class="cmtt-8"> ...</span><br class="fancyvrb" /><a
|
|---|
| 1302 | id="x1-43062r10"></a><span
|
|---|
| 1303 | class="cmr-6">10</span><span
|
|---|
| 1304 | class="cmtt-8">byte</span><span
|
|---|
| 1305 | class="cmtt-8"> n</span><span
|
|---|
| 1306 | class="cmtt-8"> [</span><span
|
|---|
| 1307 | class="cmtt-8"> </span><span
|
|---|
| 1308 | class="cmtt-8"> </span><span
|
|---|
| 1309 | class="cmtt-8"> </span><span
|
|---|
| 1310 | class="cmtt-8"> </span><span
|
|---|
| 1311 | class="cmtt-8"> </span><span
|
|---|
| 1312 | class="cmtt-8"> </span><span
|
|---|
| 1313 | class="cmtt-8"> </span><span
|
|---|
| 1314 | class="cmtt-8"> </span><span
|
|---|
| 1315 | class="cmtt-8"> </span><span
|
|---|
| 1316 | class="cmtt-8"> </span><span
|
|---|
| 1317 | class="cmtt-8"> </span><span
|
|---|
| 1318 | class="cmtt-8"> </span><span
|
|---|
| 1319 | class="cmtt-8"> </span><span
|
|---|
| 1320 | class="cmtt-8"> </span><span
|
|---|
| 1321 | class="cmtt-8"> ]</span><span
|
|---|
| 1322 | class="cmtt-8"> </span><span
|
|---|
| 1323 | class="cmtt-8"> bytestream</span><span
|
|---|
| 1324 | class="cmtt-8"> length</span><span
|
|---|
| 1325 | class="cmtt-8"> ==</span><span
|
|---|
| 1326 | class="cmtt-8"> 2</span><span
|
|---|
| 1327 | class="cmtt-8"> bytes</span><br class="fancyvrb" /><a
|
|---|
| 1328 | id="x1-43064r11"></a><span
|
|---|
| 1329 | class="cmr-6">11</span><span
|
|---|
| 1330 | class="cmtt-8"> </span><span
|
|---|
| 1331 | class="cmtt-8"> </span><span
|
|---|
| 1332 | class="cmtt-8"> </span><span
|
|---|
| 1333 | class="cmtt-8"> </span><span
|
|---|
| 1334 | class="cmtt-8"> </span><span
|
|---|
| 1335 | class="cmtt-8"> </span><span
|
|---|
| 1336 | class="cmtt-8"> </span><span
|
|---|
| 1337 | class="cmtt-8"> </span><span
|
|---|
| 1338 | class="cmtt-8"> </span><span
|
|---|
| 1339 | class="cmtt-8"> </span><span
|
|---|
| 1340 | class="cmtt-8"> </span><span
|
|---|
| 1341 | class="cmtt-8"> </span><span
|
|---|
| 1342 | class="cmtt-8"> </span><span
|
|---|
| 1343 | class="cmtt-8"> </span><span
|
|---|
| 1344 | class="cmtt-8"> </span><span
|
|---|
| 1345 | class="cmtt-8"> </span><span
|
|---|
| 1346 | class="cmtt-8"> </span><span
|
|---|
| 1347 | class="cmtt-8"> </span><span
|
|---|
| 1348 | class="cmtt-8"> </span><span
|
|---|
| 1349 | class="cmtt-8"> </span><span
|
|---|
| 1350 | class="cmtt-8"> </span><span
|
|---|
| 1351 | class="cmtt-8"> </span><span
|
|---|
| 1352 | class="cmtt-8"> </span><span
|
|---|
| 1353 | class="cmtt-8"> </span><span
|
|---|
| 1354 | class="cmtt-8"> </span><span
|
|---|
| 1355 | class="cmtt-8"> bit</span><span
|
|---|
| 1356 | class="cmtt-8"> cursor</span><span
|
|---|
| 1357 | class="cmtt-8"> ==</span><span
|
|---|
| 1358 | class="cmtt-8"> 6</span></div>
|
|---|
| 1359 | <!--l. 153--><p class="noindent" >Continue by coding the 13 bit integer value ’6969’ [b110 11001110 01]:
|
|---|
| 1360 | <!--l. 155--><p class="noindent" >
|
|---|
| 1361 | <div class="fancyvrb" id="fancyvrb5"><a
|
|---|
| 1362 | id="x1-43066r1"></a><span
|
|---|
| 1363 | class="cmr-6">1</span><span
|
|---|
| 1364 | class="cmtt-8"> </span><span
|
|---|
| 1365 | class="cmtt-8"> </span><span
|
|---|
| 1366 | class="cmtt-8"> </span><span
|
|---|
| 1367 | class="cmtt-8"> </span><span
|
|---|
| 1368 | class="cmtt-8"> </span><span
|
|---|
| 1369 | class="cmtt-8"> </span><span
|
|---|
| 1370 | class="cmtt-8"> </span><span
|
|---|
| 1371 | class="cmtt-8"> </span><span
|
|---|
| 1372 | class="cmtt-8"> </span><span
|
|---|
| 1373 | class="cmtt-8"> </span><span
|
|---|
| 1374 | class="cmtt-8"> </span><span
|
|---|
| 1375 | class="cmtt-8"> </span><span
|
|---|
| 1376 | class="cmtt-8"> </span><span
|
|---|
| 1377 | class="cmtt-8"> </span><span
|
|---|
| 1378 | class="cmtt-8"> </span><span
|
|---|
| 1379 | class="cmtt-8"> |</span><br class="fancyvrb" /><a
|
|---|
| 1380 | id="x1-43068r2"></a><span
|
|---|
| 1381 | class="cmr-6">2</span><span
|
|---|
| 1382 | class="cmtt-8"> </span><span
|
|---|
| 1383 | class="cmtt-8"> </span><span
|
|---|
| 1384 | class="cmtt-8"> </span><span
|
|---|
| 1385 | class="cmtt-8"> </span><span
|
|---|
| 1386 | class="cmtt-8"> </span><span
|
|---|
| 1387 | class="cmtt-8"> </span><span
|
|---|
| 1388 | class="cmtt-8"> </span><span
|
|---|
| 1389 | class="cmtt-8"> </span><span
|
|---|
| 1390 | class="cmtt-8"> </span><span
|
|---|
| 1391 | class="cmtt-8"> </span><span
|
|---|
| 1392 | class="cmtt-8"> </span><span
|
|---|
| 1393 | class="cmtt-8"> </span><span
|
|---|
| 1394 | class="cmtt-8"> </span><span
|
|---|
| 1395 | class="cmtt-8"> </span><span
|
|---|
| 1396 | class="cmtt-8"> </span><span
|
|---|
| 1397 | class="cmtt-8"> V</span><br class="fancyvrb" /><a
|
|---|
| 1398 | id="x1-43070r3"></a><span
|
|---|
| 1399 | class="cmr-6">3</span><br class="fancyvrb" /><a
|
|---|
| 1400 | id="x1-43072r4"></a><span
|
|---|
| 1401 | class="cmr-6">4</span><span
|
|---|
| 1402 | class="cmtt-8"> </span><span
|
|---|
| 1403 | class="cmtt-8"> </span><span
|
|---|
| 1404 | class="cmtt-8"> </span><span
|
|---|
| 1405 | class="cmtt-8"> </span><span
|
|---|
| 1406 | class="cmtt-8"> </span><span
|
|---|
| 1407 | class="cmtt-8"> </span><span
|
|---|
| 1408 | class="cmtt-8"> </span><span
|
|---|
| 1409 | class="cmtt-8"> 7</span><span
|
|---|
| 1410 | class="cmtt-8"> 6</span><span
|
|---|
| 1411 | class="cmtt-8"> 5</span><span
|
|---|
| 1412 | class="cmtt-8"> 4</span><span
|
|---|
| 1413 | class="cmtt-8"> 3</span><span
|
|---|
| 1414 | class="cmtt-8"> 2</span><span
|
|---|
| 1415 | class="cmtt-8"> 1</span><span
|
|---|
| 1416 | class="cmtt-8"> 0</span><br class="fancyvrb" /><a
|
|---|
| 1417 | id="x1-43074r5"></a><span
|
|---|
| 1418 | class="cmr-6">5</span><span
|
|---|
| 1419 | class="cmtt-8">byte</span><span
|
|---|
| 1420 | class="cmtt-8"> 0</span><span
|
|---|
| 1421 | class="cmtt-8"> [1</span><span
|
|---|
| 1422 | class="cmtt-8"> 1</span><span
|
|---|
| 1423 | class="cmtt-8"> 1</span><span
|
|---|
| 1424 | class="cmtt-8"> 1</span><span
|
|---|
| 1425 | class="cmtt-8"> 1</span><span
|
|---|
| 1426 | class="cmtt-8"> 1</span><span
|
|---|
| 1427 | class="cmtt-8"> 0</span><span
|
|---|
| 1428 | class="cmtt-8"> 0]</span><br class="fancyvrb" /><a
|
|---|
| 1429 | id="x1-43076r6"></a><span
|
|---|
| 1430 | class="cmr-6">6</span><span
|
|---|
| 1431 | class="cmtt-8">byte</span><span
|
|---|
| 1432 | class="cmtt-8"> 1</span><span
|
|---|
| 1433 | class="cmtt-8"> [0</span><span
|
|---|
| 1434 | class="cmtt-8"> 1</span><span
|
|---|
| 1435 | class="cmtt-8"> 0</span><span
|
|---|
| 1436 | class="cmtt-8"> 0</span><span
|
|---|
| 1437 | class="cmtt-8"> 1</span><span
|
|---|
| 1438 | class="cmtt-8"> 0</span><span
|
|---|
| 1439 | class="cmtt-8"> 0</span><span
|
|---|
| 1440 | class="cmtt-8"> 0]</span>
|
|---|
| 1441 | <br class="fancyvrb" /><a
|
|---|
| 1442 | id="x1-43078r7"></a><span
|
|---|
| 1443 | class="cmr-6">7</span><span
|
|---|
| 1444 | class="cmtt-8">byte</span><span
|
|---|
| 1445 | class="cmtt-8"> 2</span><span
|
|---|
| 1446 | class="cmtt-8"> [1</span><span
|
|---|
| 1447 | class="cmtt-8"> 1</span><span
|
|---|
| 1448 | class="cmtt-8"> 0</span><span
|
|---|
| 1449 | class="cmtt-8"> 0</span><span
|
|---|
| 1450 | class="cmtt-8"> 1</span><span
|
|---|
| 1451 | class="cmtt-8"> 1</span><span
|
|---|
| 1452 | class="cmtt-8"> 1</span><span
|
|---|
| 1453 | class="cmtt-8"> 0]</span><br class="fancyvrb" /><a
|
|---|
| 1454 | id="x1-43080r8"></a><span
|
|---|
| 1455 | class="cmr-6">8</span><span
|
|---|
| 1456 | class="cmtt-8">byte</span><span
|
|---|
| 1457 | class="cmtt-8"> 3</span><span
|
|---|
| 1458 | class="cmtt-8"> [0</span><span
|
|---|
| 1459 | class="cmtt-8"> 0</span><span
|
|---|
| 1460 | class="cmtt-8"> 0</span><span
|
|---|
| 1461 | class="cmtt-8"> 0</span><span
|
|---|
| 1462 | class="cmtt-8"> 0</span><span
|
|---|
| 1463 | class="cmtt-8"> 1</span><span
|
|---|
| 1464 | class="cmtt-8"> 1</span><span
|
|---|
| 1465 | class="cmtt-8"> 0]</span><span
|
|---|
| 1466 | class="cmtt-8"> </span><span
|
|---|
| 1467 | class="cmtt-8"> <-</span><br class="fancyvrb" /><a
|
|---|
| 1468 | id="x1-43082r9"></a><span
|
|---|
| 1469 | class="cmr-6">9</span><span
|
|---|
| 1470 | class="cmtt-8"> </span><span
|
|---|
| 1471 | class="cmtt-8"> </span><span
|
|---|
| 1472 | class="cmtt-8"> </span><span
|
|---|
| 1473 | class="cmtt-8"> </span><span
|
|---|
| 1474 | class="cmtt-8"> </span><span
|
|---|
| 1475 | class="cmtt-8"> </span><span
|
|---|
| 1476 | class="cmtt-8"> </span><span
|
|---|
| 1477 | class="cmtt-8"> </span><span
|
|---|
| 1478 | class="cmtt-8"> </span><span
|
|---|
| 1479 | class="cmtt-8"> </span><span
|
|---|
| 1480 | class="cmtt-8"> </span><span
|
|---|
| 1481 | class="cmtt-8"> </span><span
|
|---|
| 1482 | class="cmtt-8"> ...</span><br class="fancyvrb" /><a
|
|---|
| 1483 | id="x1-43084r10"></a><span
|
|---|
| 1484 | class="cmr-6">10</span><span
|
|---|
| 1485 | class="cmtt-8">byte</span><span
|
|---|
| 1486 | class="cmtt-8"> n</span><span
|
|---|
| 1487 | class="cmtt-8"> [</span><span
|
|---|
| 1488 | class="cmtt-8"> </span><span
|
|---|
| 1489 | class="cmtt-8"> </span><span
|
|---|
| 1490 | class="cmtt-8"> </span><span
|
|---|
| 1491 | class="cmtt-8"> </span><span
|
|---|
| 1492 | class="cmtt-8"> </span><span
|
|---|
| 1493 | class="cmtt-8"> </span><span
|
|---|
| 1494 | class="cmtt-8"> </span><span
|
|---|
| 1495 | class="cmtt-8"> </span><span
|
|---|
| 1496 | class="cmtt-8"> </span><span
|
|---|
| 1497 | class="cmtt-8"> </span><span
|
|---|
| 1498 | class="cmtt-8"> </span><span
|
|---|
| 1499 | class="cmtt-8"> </span><span
|
|---|
| 1500 | class="cmtt-8"> </span><span
|
|---|
| 1501 | class="cmtt-8"> </span><span
|
|---|
| 1502 | class="cmtt-8"> ]</span><span
|
|---|
| 1503 | class="cmtt-8"> </span><span
|
|---|
| 1504 | class="cmtt-8"> bytestream</span><span
|
|---|
| 1505 | class="cmtt-8"> length</span><span
|
|---|
| 1506 | class="cmtt-8"> ==</span><span
|
|---|
| 1507 | class="cmtt-8"> 4</span><span
|
|---|
| 1508 | class="cmtt-8"> bytes</span><br class="fancyvrb" /><a
|
|---|
| 1509 | id="x1-43086r11"></a><span
|
|---|
| 1510 | class="cmr-6">11</span></div>
|
|---|
| 1511 |
|
|---|
| 1512 |
|
|---|
| 1513 |
|
|---|
| 1514 | <!--l. 172--><p class="noindent" >
|
|---|
| 1515 | <h5 class="subsubsectionHead"><span class="titlemark">2.1.7. </span> <a
|
|---|
| 1516 | id="x1-440002.1.7"></a>decoding example</h5>
|
|---|
| 1517 | <!--l. 174--><p class="noindent" >Reading from the beginning of the bytestream encoded in the above example:
|
|---|
| 1518 | <!--l. 176--><p class="noindent" >
|
|---|
| 1519 | <div class="fancyvrb" id="fancyvrb6"><a
|
|---|
| 1520 | id="x1-44002r1"></a><span
|
|---|
| 1521 | class="cmr-6">1</span><span
|
|---|
| 1522 | class="cmtt-8"> </span><span
|
|---|
| 1523 | class="cmtt-8"> </span><span
|
|---|
| 1524 | class="cmtt-8"> </span><span
|
|---|
| 1525 | class="cmtt-8"> </span><span
|
|---|
| 1526 | class="cmtt-8"> </span><span
|
|---|
| 1527 | class="cmtt-8"> </span><span
|
|---|
| 1528 | class="cmtt-8"> </span><span
|
|---|
| 1529 | class="cmtt-8"> </span><span
|
|---|
| 1530 | class="cmtt-8"> </span><span
|
|---|
| 1531 | class="cmtt-8"> </span><span
|
|---|
| 1532 | class="cmtt-8"> </span><span
|
|---|
| 1533 | class="cmtt-8"> </span><span
|
|---|
| 1534 | class="cmtt-8"> </span><span
|
|---|
| 1535 | class="cmtt-8"> </span><span
|
|---|
| 1536 | class="cmtt-8"> </span><span
|
|---|
| 1537 | class="cmtt-8"> </span><span
|
|---|
| 1538 | class="cmtt-8"> </span><span
|
|---|
| 1539 | class="cmtt-8"> </span><span
|
|---|
| 1540 | class="cmtt-8"> </span><span
|
|---|
| 1541 | class="cmtt-8"> </span><span
|
|---|
| 1542 | class="cmtt-8"> </span><span
|
|---|
| 1543 | class="cmtt-8"> |</span><br class="fancyvrb" /><a
|
|---|
| 1544 | id="x1-44004r2"></a><span
|
|---|
| 1545 | class="cmr-6">2</span><span
|
|---|
| 1546 | class="cmtt-8"> </span><span
|
|---|
| 1547 | class="cmtt-8"> </span><span
|
|---|
| 1548 | class="cmtt-8"> </span><span
|
|---|
| 1549 | class="cmtt-8"> </span><span
|
|---|
| 1550 | class="cmtt-8"> </span><span
|
|---|
| 1551 | class="cmtt-8"> </span><span
|
|---|
| 1552 | class="cmtt-8"> </span><span
|
|---|
| 1553 | class="cmtt-8"> </span><span
|
|---|
| 1554 | class="cmtt-8"> </span><span
|
|---|
| 1555 | class="cmtt-8"> </span><span
|
|---|
| 1556 | class="cmtt-8"> </span><span
|
|---|
| 1557 | class="cmtt-8"> </span><span
|
|---|
| 1558 | class="cmtt-8"> </span><span
|
|---|
| 1559 | class="cmtt-8"> </span><span
|
|---|
| 1560 | class="cmtt-8"> </span><span
|
|---|
| 1561 | class="cmtt-8"> </span><span
|
|---|
| 1562 | class="cmtt-8"> </span><span
|
|---|
| 1563 | class="cmtt-8"> </span><span
|
|---|
| 1564 | class="cmtt-8"> </span><span
|
|---|
| 1565 | class="cmtt-8"> </span><span
|
|---|
| 1566 | class="cmtt-8"> </span><span
|
|---|
| 1567 | class="cmtt-8"> V</span><br class="fancyvrb" /><a
|
|---|
| 1568 | id="x1-44006r3"></a><span
|
|---|
| 1569 | class="cmr-6">3</span><br class="fancyvrb" /><a
|
|---|
| 1570 | id="x1-44008r4"></a><span
|
|---|
| 1571 | class="cmr-6">4</span><span
|
|---|
| 1572 | class="cmtt-8"> </span><span
|
|---|
| 1573 | class="cmtt-8"> </span><span
|
|---|
| 1574 | class="cmtt-8"> </span><span
|
|---|
| 1575 | class="cmtt-8"> </span><span
|
|---|
| 1576 | class="cmtt-8"> </span><span
|
|---|
| 1577 | class="cmtt-8"> </span><span
|
|---|
| 1578 | class="cmtt-8"> </span><span
|
|---|
| 1579 | class="cmtt-8"> 7</span><span
|
|---|
| 1580 | class="cmtt-8"> 6</span><span
|
|---|
| 1581 | class="cmtt-8"> 5</span><span
|
|---|
| 1582 | class="cmtt-8"> 4</span><span
|
|---|
| 1583 | class="cmtt-8"> 3</span><span
|
|---|
| 1584 | class="cmtt-8"> 2</span><span
|
|---|
| 1585 | class="cmtt-8"> 1</span><span
|
|---|
| 1586 | class="cmtt-8"> 0</span><br class="fancyvrb" /><a
|
|---|
| 1587 | id="x1-44010r5"></a><span
|
|---|
| 1588 | class="cmr-6">5</span><span
|
|---|
| 1589 | class="cmtt-8">byte</span><span
|
|---|
| 1590 | class="cmtt-8"> 0</span><span
|
|---|
| 1591 | class="cmtt-8"> [1</span><span
|
|---|
| 1592 | class="cmtt-8"> 1</span><span
|
|---|
| 1593 | class="cmtt-8"> 1</span><span
|
|---|
| 1594 | class="cmtt-8"> 1</span><span
|
|---|
| 1595 | class="cmtt-8"> 1</span><span
|
|---|
| 1596 | class="cmtt-8"> 1</span><span
|
|---|
| 1597 | class="cmtt-8"> 0</span><span
|
|---|
| 1598 | class="cmtt-8"> 0]</span><span
|
|---|
| 1599 | class="cmtt-8"> </span><span
|
|---|
| 1600 | class="cmtt-8"> <-</span><br class="fancyvrb" /><a
|
|---|
| 1601 | id="x1-44012r6"></a><span
|
|---|
| 1602 | class="cmr-6">6</span><span
|
|---|
| 1603 | class="cmtt-8">byte</span><span
|
|---|
| 1604 | class="cmtt-8"> 1</span><span
|
|---|
| 1605 | class="cmtt-8"> [0</span><span
|
|---|
| 1606 | class="cmtt-8"> 1</span><span
|
|---|
| 1607 | class="cmtt-8"> 0</span><span
|
|---|
| 1608 | class="cmtt-8"> 0</span><span
|
|---|
| 1609 | class="cmtt-8"> 1</span><span
|
|---|
| 1610 | class="cmtt-8"> 0</span><span
|
|---|
| 1611 | class="cmtt-8"> 0</span><span
|
|---|
| 1612 | class="cmtt-8"> 0]</span>
|
|---|
| 1613 | <br class="fancyvrb" /><a
|
|---|
| 1614 | id="x1-44014r7"></a><span
|
|---|
| 1615 | class="cmr-6">7</span><span
|
|---|
| 1616 | class="cmtt-8">byte</span><span
|
|---|
| 1617 | class="cmtt-8"> 2</span><span
|
|---|
| 1618 | class="cmtt-8"> [1</span><span
|
|---|
| 1619 | class="cmtt-8"> 1</span><span
|
|---|
| 1620 | class="cmtt-8"> 0</span><span
|
|---|
| 1621 | class="cmtt-8"> 0</span><span
|
|---|
| 1622 | class="cmtt-8"> 1</span><span
|
|---|
| 1623 | class="cmtt-8"> 1</span><span
|
|---|
| 1624 | class="cmtt-8"> 1</span><span
|
|---|
| 1625 | class="cmtt-8"> 0]</span><br class="fancyvrb" /><a
|
|---|
| 1626 | id="x1-44016r8"></a><span
|
|---|
| 1627 | class="cmr-6">8</span><span
|
|---|
| 1628 | class="cmtt-8">byte</span><span
|
|---|
| 1629 | class="cmtt-8"> 3</span><span
|
|---|
| 1630 | class="cmtt-8"> [0</span><span
|
|---|
| 1631 | class="cmtt-8"> 0</span><span
|
|---|
| 1632 | class="cmtt-8"> 0</span><span
|
|---|
| 1633 | class="cmtt-8"> 0</span><span
|
|---|
| 1634 | class="cmtt-8"> 0</span><span
|
|---|
| 1635 | class="cmtt-8"> 1</span><span
|
|---|
| 1636 | class="cmtt-8"> 1</span><span
|
|---|
| 1637 | class="cmtt-8"> 0]</span><span
|
|---|
| 1638 | class="cmtt-8"> </span><span
|
|---|
| 1639 | class="cmtt-8"> bytestream</span><span
|
|---|
| 1640 | class="cmtt-8"> length</span><span
|
|---|
| 1641 | class="cmtt-8"> ==</span><span
|
|---|
| 1642 | class="cmtt-8"> 4</span><span
|
|---|
| 1643 | class="cmtt-8"> bytes</span><br class="fancyvrb" /><a
|
|---|
| 1644 | id="x1-44018r9"></a><span
|
|---|
| 1645 | class="cmr-6">9</span></div>
|
|---|
| 1646 | <!--l. 189--><p class="noindent" >We read two, two-bit integer fields, resulting in the returned numbers ’b00’ and ’b11’. Two things
|
|---|
| 1647 | are worth noting here:
|
|---|
| 1648 | <ul class="itemize1">
|
|---|
| 1649 | <li class="itemize">Although these four bits were originally written as a single four-bit integer, reading
|
|---|
| 1650 | some other combination of bit-widths from the bitstream is well defined. There are
|
|---|
| 1651 | no artificial alignment boundaries maintained in the bitstream.
|
|---|
| 1652 | </li>
|
|---|
| 1653 | <li class="itemize">The second value is the two-bit-wide integer ’b11’. This value may be interpreted
|
|---|
| 1654 | either as the unsigned value ’3’, or the signed value ’-1’. Signedness is dependent on
|
|---|
| 1655 | decode context.</li></ul>
|
|---|
| 1656 | <!--l. 207--><p class="noindent" >
|
|---|
| 1657 | <h5 class="subsubsectionHead"><span class="titlemark">2.1.8. </span> <a
|
|---|
| 1658 | id="x1-450002.1.8"></a>end-of-packet alignment</h5>
|
|---|
| 1659 | <!--l. 209--><p class="noindent" >The typical use of bitpacking is to produce many independent byte-aligned packets which are
|
|---|
| 1660 | embedded into a larger byte-aligned container structure, such as an Ogg transport bitstream.
|
|---|
| 1661 | Externally, each bytestream (encoded bitstream) must begin and end on a byte boundary. Often,
|
|---|
| 1662 | the encoded bitstream is not an integer number of bytes, and so there is unused (uncoded) space
|
|---|
| 1663 | in the last byte of a packet.
|
|---|
| 1664 | <!--l. 217--><p class="noindent" >Unused space in the last byte of a bytestream is always zeroed during the coding process. Thus,
|
|---|
| 1665 | should this unused space be read, it will return binary zeroes.
|
|---|
| 1666 | <!--l. 221--><p class="noindent" >Attempting to read past the end of an encoded packet results in an ’end-of-packet’ condition.
|
|---|
| 1667 | End-of-packet is not to be considered an error; it is merely a state indicating that there is
|
|---|
| 1668 | insufficient remaining data to fulfill the desired read size. Vorbis uses truncated packets as a
|
|---|
| 1669 |
|
|---|
| 1670 |
|
|---|
| 1671 |
|
|---|
| 1672 | normal mode of operation, and as such, decoders must handle reading past the end of a packet as
|
|---|
| 1673 | a typical mode of operation. Any further read operations after an ’end-of-packet’ condition shall
|
|---|
| 1674 | also return ’end-of-packet’.
|
|---|
| 1675 | <!--l. 232--><p class="noindent" >
|
|---|
| 1676 | <h5 class="subsubsectionHead"><span class="titlemark">2.1.9. </span> <a
|
|---|
| 1677 | id="x1-460002.1.9"></a>reading zero bits</h5>
|
|---|
| 1678 | <!--l. 234--><p class="noindent" >Reading a zero-bit-wide integer returns the value ’0’ and does not increment the stream cursor.
|
|---|
| 1679 | Reading to the end of the packet (but not past, such that an ’end-of-packet’ condition has not
|
|---|
| 1680 | triggered) and then reading a zero bit integer shall succeed, returning 0, and not trigger an
|
|---|
| 1681 | end-of-packet condition. Reading a zero-bit-wide integer after a previous read sets ’end-of-packet’
|
|---|
| 1682 | shall also fail with ’end-of-packet’.
|
|---|
| 1683 |
|
|---|
| 1684 |
|
|---|
| 1685 |
|
|---|
| 1686 |
|
|---|
| 1687 |
|
|---|
| 1688 |
|
|---|
| 1689 | <h3 class="sectionHead"><span class="titlemark">3. </span> <a
|
|---|
| 1690 | id="x1-470003"></a>Probability Model and Codebooks</h3>
|
|---|
| 1691 | <!--l. 5--><p class="noindent" >
|
|---|
| 1692 | <h4 class="subsectionHead"><span class="titlemark">3.1. </span> <a
|
|---|
| 1693 | id="x1-480003.1"></a>Overview</h4>
|
|---|
| 1694 | <!--l. 7--><p class="noindent" >Unlike practically every other mainstream audio codec, Vorbis has no statically configured
|
|---|
| 1695 | probability model, instead packing all entropy decoding configuration, VQ and Huffman, into the
|
|---|
| 1696 | bitstream itself in the third header, the codec setup header. This packed configuration consists of
|
|---|
| 1697 | multiple ’codebooks’, each containing a specific Huffman-equivalent representation for decoding
|
|---|
| 1698 | compressed codewords as well as an optional lookup table of output vector values to which a
|
|---|
| 1699 | decoded Huffman value is applied as an offset, generating the final decoded output corresponding
|
|---|
| 1700 | to a given compressed codeword.
|
|---|
| 1701 | <!--l. 17--><p class="noindent" >
|
|---|
| 1702 | <h5 class="subsubsectionHead"><span class="titlemark">3.1.1. </span> <a
|
|---|
| 1703 | id="x1-490003.1.1"></a>Bitwise operation</h5>
|
|---|
| 1704 | <!--l. 18--><p class="noindent" >The codebook mechanism is built on top of the vorbis bitpacker. Both the codebooks themselves
|
|---|
| 1705 | and the codewords they decode are unrolled from a packet as a series of arbitrary-width values
|
|---|
| 1706 | read from the stream according to <a
|
|---|
| 1707 | href="#x1-360002">section 2</a>, “<a
|
|---|
| 1708 | href="#x1-360002">Bitpacking Convention<!--tex4ht:ref: vorbis:spec:bitpacking --></a>”.
|
|---|
| 1709 | <!--l. 26--><p class="noindent" >
|
|---|
| 1710 | <h4 class="subsectionHead"><span class="titlemark">3.2. </span> <a
|
|---|
| 1711 | id="x1-500003.2"></a>Packed codebook format</h4>
|
|---|
| 1712 | <!--l. 28--><p class="noindent" >For purposes of the examples below, we assume that the storage system’s native byte width is
|
|---|
| 1713 | eight bits. This is not universally true; see <a
|
|---|
| 1714 | href="#x1-360002">section 2</a>, “<a
|
|---|
| 1715 | href="#x1-360002">Bitpacking Convention<!--tex4ht:ref: vorbis:spec:bitpacking --></a>” for discussion
|
|---|
| 1716 | relating to non-eight-bit bytes.
|
|---|
| 1717 |
|
|---|
| 1718 |
|
|---|
| 1719 |
|
|---|
| 1720 | <!--l. 33--><p class="noindent" >
|
|---|
| 1721 | <h5 class="subsubsectionHead"><span class="titlemark">3.2.1. </span> <a
|
|---|
| 1722 | id="x1-510003.2.1"></a>codebook decode</h5>
|
|---|
| 1723 | <!--l. 35--><p class="noindent" >A codebook begins with a 24 bit sync pattern, 0x564342:
|
|---|
| 1724 | <!--l. 37--><p class="noindent" >
|
|---|
| 1725 | <div class="fancyvrb" id="fancyvrb7"><a
|
|---|
| 1726 | id="x1-51002r1"></a><span
|
|---|
| 1727 | class="cmr-6">1</span><span
|
|---|
| 1728 | class="cmtt-8">byte</span><span
|
|---|
| 1729 | class="cmtt-8"> 0:</span><span
|
|---|
| 1730 | class="cmtt-8"> [</span><span
|
|---|
| 1731 | class="cmtt-8"> 0</span><span
|
|---|
| 1732 | class="cmtt-8"> 1</span><span
|
|---|
| 1733 | class="cmtt-8"> 0</span><span
|
|---|
| 1734 | class="cmtt-8"> 0</span><span
|
|---|
| 1735 | class="cmtt-8"> 0</span><span
|
|---|
| 1736 | class="cmtt-8"> 0</span><span
|
|---|
| 1737 | class="cmtt-8"> 1</span><span
|
|---|
| 1738 | class="cmtt-8"> 0</span><span
|
|---|
| 1739 | class="cmtt-8"> ]</span><span
|
|---|
| 1740 | class="cmtt-8"> (0x42)</span><br class="fancyvrb" /><a
|
|---|
| 1741 | id="x1-51004r2"></a><span
|
|---|
| 1742 | class="cmr-6">2</span><span
|
|---|
| 1743 | class="cmtt-8">byte</span><span
|
|---|
| 1744 | class="cmtt-8"> 1:</span><span
|
|---|
| 1745 | class="cmtt-8"> [</span><span
|
|---|
| 1746 | class="cmtt-8"> 0</span><span
|
|---|
| 1747 | class="cmtt-8"> 1</span><span
|
|---|
| 1748 | class="cmtt-8"> 0</span><span
|
|---|
| 1749 | class="cmtt-8"> 0</span><span
|
|---|
| 1750 | class="cmtt-8"> 0</span><span
|
|---|
| 1751 | class="cmtt-8"> 0</span><span
|
|---|
| 1752 | class="cmtt-8"> 1</span><span
|
|---|
| 1753 | class="cmtt-8"> 1</span><span
|
|---|
| 1754 | class="cmtt-8"> ]</span><span
|
|---|
| 1755 | class="cmtt-8"> (0x43)</span><br class="fancyvrb" /><a
|
|---|
| 1756 | id="x1-51006r3"></a><span
|
|---|
| 1757 | class="cmr-6">3</span><span
|
|---|
| 1758 | class="cmtt-8">byte</span><span
|
|---|
| 1759 | class="cmtt-8"> 2:</span><span
|
|---|
| 1760 | class="cmtt-8"> [</span><span
|
|---|
| 1761 | class="cmtt-8"> 0</span><span
|
|---|
| 1762 | class="cmtt-8"> 1</span><span
|
|---|
| 1763 | class="cmtt-8"> 0</span><span
|
|---|
| 1764 | class="cmtt-8"> 1</span><span
|
|---|
| 1765 | class="cmtt-8"> 0</span><span
|
|---|
| 1766 | class="cmtt-8"> 1</span><span
|
|---|
| 1767 | class="cmtt-8"> 1</span><span
|
|---|
| 1768 | class="cmtt-8"> 0</span><span
|
|---|
| 1769 | class="cmtt-8"> ]</span><span
|
|---|
| 1770 | class="cmtt-8"> (0x56)</span></div>
|
|---|
| 1771 | <!--l. 43--><p class="noindent" >16 bit <span
|
|---|
| 1772 | class="cmtt-12">[codebook</span><span
|
|---|
| 1773 | class="cmtt-12">_dimensions] </span>and 24 bit <span
|
|---|
| 1774 | class="cmtt-12">[codebook</span><span
|
|---|
| 1775 | class="cmtt-12">_entries] </span>fields:
|
|---|
| 1776 | <!--l. 45--><p class="noindent" >
|
|---|
| 1777 | <div class="fancyvrb" id="fancyvrb8"><a
|
|---|
| 1778 | id="x1-51008r1"></a><span
|
|---|
| 1779 | class="cmr-6">1</span><br class="fancyvrb" /><a
|
|---|
| 1780 | id="x1-51010r2"></a><span
|
|---|
| 1781 | class="cmr-6">2</span><span
|
|---|
| 1782 | class="cmtt-8">byte</span><span
|
|---|
| 1783 | class="cmtt-8"> 3:</span><span
|
|---|
| 1784 | class="cmtt-8"> [</span><span
|
|---|
| 1785 | class="cmtt-8"> X</span><span
|
|---|
| 1786 | class="cmtt-8"> X</span><span
|
|---|
| 1787 | class="cmtt-8"> X</span><span
|
|---|
| 1788 | class="cmtt-8"> X</span><span
|
|---|
| 1789 | class="cmtt-8"> X</span><span
|
|---|
| 1790 | class="cmtt-8"> X</span><span
|
|---|
| 1791 | class="cmtt-8"> X</span><span
|
|---|
| 1792 | class="cmtt-8"> X</span><span
|
|---|
| 1793 | class="cmtt-8"> ]</span><br class="fancyvrb" /><a
|
|---|
| 1794 | id="x1-51012r3"></a><span
|
|---|
| 1795 | class="cmr-6">3</span><span
|
|---|
| 1796 | class="cmtt-8">byte</span><span
|
|---|
| 1797 | class="cmtt-8"> 4:</span><span
|
|---|
| 1798 | class="cmtt-8"> [</span><span
|
|---|
| 1799 | class="cmtt-8"> X</span><span
|
|---|
| 1800 | class="cmtt-8"> X</span><span
|
|---|
| 1801 | class="cmtt-8"> X</span><span
|
|---|
| 1802 | class="cmtt-8"> X</span><span
|
|---|
| 1803 | class="cmtt-8"> X</span><span
|
|---|
| 1804 | class="cmtt-8"> X</span><span
|
|---|
| 1805 | class="cmtt-8"> X</span><span
|
|---|
| 1806 | class="cmtt-8"> X</span><span
|
|---|
| 1807 | class="cmtt-8"> ]</span><span
|
|---|
| 1808 | class="cmtt-8"> [codebook</span><span
|
|---|
| 1809 | class="cmtt-8">_dimensions]</span><span
|
|---|
| 1810 | class="cmtt-8"> (16</span><span
|
|---|
| 1811 | class="cmtt-8"> bit</span><span
|
|---|
| 1812 | class="cmtt-8"> unsigned)</span><br class="fancyvrb" /><a
|
|---|
| 1813 | id="x1-51014r4"></a><span
|
|---|
| 1814 | class="cmr-6">4</span><br class="fancyvrb" /><a
|
|---|
| 1815 | id="x1-51016r5"></a><span
|
|---|
| 1816 | class="cmr-6">5</span><span
|
|---|
| 1817 | class="cmtt-8">byte</span><span
|
|---|
| 1818 | class="cmtt-8"> 5:</span><span
|
|---|
| 1819 | class="cmtt-8"> [</span><span
|
|---|
| 1820 | class="cmtt-8"> X</span><span
|
|---|
| 1821 | class="cmtt-8"> X</span><span
|
|---|
| 1822 | class="cmtt-8"> X</span><span
|
|---|
| 1823 | class="cmtt-8"> X</span><span
|
|---|
| 1824 | class="cmtt-8"> X</span><span
|
|---|
| 1825 | class="cmtt-8"> X</span><span
|
|---|
| 1826 | class="cmtt-8"> X</span><span
|
|---|
| 1827 | class="cmtt-8"> X</span><span
|
|---|
| 1828 | class="cmtt-8"> ]</span>
|
|---|
| 1829 | <br class="fancyvrb" /><a
|
|---|
| 1830 | id="x1-51018r6"></a><span
|
|---|
| 1831 | class="cmr-6">6</span><span
|
|---|
| 1832 | class="cmtt-8">byte</span><span
|
|---|
| 1833 | class="cmtt-8"> 6:</span><span
|
|---|
| 1834 | class="cmtt-8"> [</span><span
|
|---|
| 1835 | class="cmtt-8"> X</span><span
|
|---|
| 1836 | class="cmtt-8"> X</span><span
|
|---|
| 1837 | class="cmtt-8"> X</span><span
|
|---|
| 1838 | class="cmtt-8"> X</span><span
|
|---|
| 1839 | class="cmtt-8"> X</span><span
|
|---|
| 1840 | class="cmtt-8"> X</span><span
|
|---|
| 1841 | class="cmtt-8"> X</span><span
|
|---|
| 1842 | class="cmtt-8"> X</span><span
|
|---|
| 1843 | class="cmtt-8"> ]</span><br class="fancyvrb" /><a
|
|---|
| 1844 | id="x1-51020r7"></a><span
|
|---|
| 1845 | class="cmr-6">7</span><span
|
|---|
| 1846 | class="cmtt-8">byte</span><span
|
|---|
| 1847 | class="cmtt-8"> 7:</span><span
|
|---|
| 1848 | class="cmtt-8"> [</span><span
|
|---|
| 1849 | class="cmtt-8"> X</span><span
|
|---|
| 1850 | class="cmtt-8"> X</span><span
|
|---|
| 1851 | class="cmtt-8"> X</span><span
|
|---|
| 1852 | class="cmtt-8"> X</span><span
|
|---|
| 1853 | class="cmtt-8"> X</span><span
|
|---|
| 1854 | class="cmtt-8"> X</span><span
|
|---|
| 1855 | class="cmtt-8"> X</span><span
|
|---|
| 1856 | class="cmtt-8"> X</span><span
|
|---|
| 1857 | class="cmtt-8"> ]</span><span
|
|---|
| 1858 | class="cmtt-8"> [codebook</span><span
|
|---|
| 1859 | class="cmtt-8">_entries]</span><span
|
|---|
| 1860 | class="cmtt-8"> (24</span><span
|
|---|
| 1861 | class="cmtt-8"> bit</span><span
|
|---|
| 1862 | class="cmtt-8"> unsigned)</span><br class="fancyvrb" /><a
|
|---|
| 1863 | id="x1-51022r8"></a><span
|
|---|
| 1864 | class="cmr-6">8</span></div>
|
|---|
| 1865 | <!--l. 56--><p class="noindent" >Next is the <span
|
|---|
| 1866 | class="cmtt-12">[ordered] </span>bit flag:
|
|---|
| 1867 | <!--l. 58--><p class="noindent" >
|
|---|
| 1868 | <div class="fancyvrb" id="fancyvrb9"><a
|
|---|
| 1869 | id="x1-51024r1"></a><span
|
|---|
| 1870 | class="cmr-6">1</span><br class="fancyvrb" /><a
|
|---|
| 1871 | id="x1-51026r2"></a><span
|
|---|
| 1872 | class="cmr-6">2</span><span
|
|---|
| 1873 | class="cmtt-8">byte</span><span
|
|---|
| 1874 | class="cmtt-8"> 8:</span><span
|
|---|
| 1875 | class="cmtt-8"> [</span><span
|
|---|
| 1876 | class="cmtt-8"> </span><span
|
|---|
| 1877 | class="cmtt-8"> </span><span
|
|---|
| 1878 | class="cmtt-8"> </span><span
|
|---|
| 1879 | class="cmtt-8"> </span><span
|
|---|
| 1880 | class="cmtt-8"> </span><span
|
|---|
| 1881 | class="cmtt-8"> </span><span
|
|---|
| 1882 | class="cmtt-8"> </span><span
|
|---|
| 1883 | class="cmtt-8"> </span><span
|
|---|
| 1884 | class="cmtt-8"> </span><span
|
|---|
| 1885 | class="cmtt-8"> </span><span
|
|---|
| 1886 | class="cmtt-8"> </span><span
|
|---|
| 1887 | class="cmtt-8"> </span><span
|
|---|
| 1888 | class="cmtt-8"> </span><span
|
|---|
| 1889 | class="cmtt-8"> </span><span
|
|---|
| 1890 | class="cmtt-8"> X</span><span
|
|---|
| 1891 | class="cmtt-8"> ]</span><span
|
|---|
| 1892 | class="cmtt-8"> [ordered]</span><span
|
|---|
| 1893 | class="cmtt-8"> (1</span><span
|
|---|
| 1894 | class="cmtt-8"> bit)</span><br class="fancyvrb" /><a
|
|---|
| 1895 | id="x1-51028r3"></a><span
|
|---|
| 1896 | class="cmr-6">3</span></div>
|
|---|
| 1897 | <!--l. 64--><p class="noindent" >Each entry, numbering a total of <span
|
|---|
| 1898 | class="cmtt-12">[codebook</span><span
|
|---|
| 1899 | class="cmtt-12">_entries]</span>, is assigned a codeword length.
|
|---|
| 1900 | We now read the list of codeword lengths and store these lengths in the array
|
|---|
| 1901 | <span
|
|---|
| 1902 | class="cmtt-12">[codebook</span><span
|
|---|
| 1903 | class="cmtt-12">_codeword</span><span
|
|---|
| 1904 | class="cmtt-12">_lengths]</span>. Decode of lengths is according to whether the <span
|
|---|
| 1905 | class="cmtt-12">[ordered] </span>flag
|
|---|
| 1906 | is set or unset.
|
|---|
| 1907 | <ul class="itemize1">
|
|---|
| 1908 | <li class="itemize">If the <span
|
|---|
| 1909 | class="cmtt-12">[ordered] </span>flag is unset, the codeword list is not length ordered and the decoder
|
|---|
| 1910 | needs to read each codeword length one-by-one.
|
|---|
| 1911 | <!--l. 76--><p class="noindent" >The decoder first reads one additional bit flag, the <span
|
|---|
| 1912 | class="cmtt-12">[sparse] </span>flag. This flag determines
|
|---|
| 1913 | whether or not the codebook contains unused entries that are not to be included in
|
|---|
| 1914 | the codeword decode tree:
|
|---|
| 1915 | <!--l. 81--><p class="noindent" >
|
|---|
| 1916 | <div class="fancyvrb" id="fancyvrb10"><a
|
|---|
| 1917 | id="x1-51030r1"></a><span
|
|---|
| 1918 | class="cmr-6">1</span><span
|
|---|
| 1919 | class="cmtt-8">byte</span><span
|
|---|
| 1920 | class="cmtt-8"> 8:</span><span
|
|---|
| 1921 | class="cmtt-8"> [</span><span
|
|---|
| 1922 | class="cmtt-8"> </span><span
|
|---|
| 1923 | class="cmtt-8"> </span><span
|
|---|
| 1924 | class="cmtt-8"> </span><span
|
|---|
| 1925 | class="cmtt-8"> </span><span
|
|---|
| 1926 | class="cmtt-8"> </span><span
|
|---|
| 1927 | class="cmtt-8"> </span><span
|
|---|
| 1928 | class="cmtt-8"> </span><span
|
|---|
| 1929 | class="cmtt-8"> </span><span
|
|---|
| 1930 | class="cmtt-8"> </span><span
|
|---|
| 1931 | class="cmtt-8"> </span><span
|
|---|
| 1932 | class="cmtt-8"> </span><span
|
|---|
| 1933 | class="cmtt-8"> </span><span
|
|---|
| 1934 | class="cmtt-8"> X</span><span
|
|---|
| 1935 | class="cmtt-8"> 1</span><span
|
|---|
| 1936 | class="cmtt-8"> ]</span><span
|
|---|
| 1937 | class="cmtt-8"> [sparse]</span><span
|
|---|
| 1938 | class="cmtt-8"> flag</span><span
|
|---|
| 1939 | class="cmtt-8"> (1</span><span
|
|---|
| 1940 | class="cmtt-8"> bit)</span></div>
|
|---|
| 1941 | <!--l. 85--><p class="noindent" >The decoder now performs for each of the <span
|
|---|
| 1942 | class="cmtt-12">[codebook</span><span
|
|---|
| 1943 | class="cmtt-12">_entries] </span>codebook entries:
|
|---|
| 1944 | <!--l. 88--><p class="noindent" >
|
|---|
| 1945 | <div class="fancyvrb" id="fancyvrb11"><a
|
|---|
| 1946 | id="x1-51032r1"></a><span
|
|---|
| 1947 | class="cmr-6">1</span><br class="fancyvrb" /><a
|
|---|
| 1948 | id="x1-51034r2"></a><span
|
|---|
| 1949 | class="cmr-6">2</span><span
|
|---|
| 1950 | class="cmtt-8"> </span><span
|
|---|
| 1951 | class="cmtt-8"> 1)</span><span
|
|---|
| 1952 | class="cmtt-8"> if([sparse]</span><span
|
|---|
| 1953 | class="cmtt-8"> is</span><span
|
|---|
| 1954 | class="cmtt-8"> set)</span><span
|
|---|
| 1955 | class="cmtt-8"> </span><span
|
|---|
| 1956 | class="cmsy-8">{</span><br class="fancyvrb" /><a
|
|---|
| 1957 | id="x1-51036r3"></a><span
|
|---|
| 1958 | class="cmr-6">3</span><br class="fancyvrb" /><a
|
|---|
| 1959 | id="x1-51038r4"></a><span
|
|---|
| 1960 | class="cmr-6">4</span><span
|
|---|
| 1961 | class="cmtt-8"> </span><span
|
|---|
| 1962 | class="cmtt-8"> </span><span
|
|---|
| 1963 | class="cmtt-8"> </span><span
|
|---|
| 1964 | class="cmtt-8"> </span><span
|
|---|
| 1965 | class="cmtt-8"> </span><span
|
|---|
| 1966 | class="cmtt-8"> </span><span
|
|---|
| 1967 | class="cmtt-8"> </span><span
|
|---|
| 1968 | class="cmtt-8"> </span><span
|
|---|
| 1969 | class="cmtt-8"> 2)</span><span
|
|---|
| 1970 | class="cmtt-8"> [flag]</span><span
|
|---|
| 1971 | class="cmtt-8"> =</span><span
|
|---|
| 1972 | class="cmtt-8"> read</span><span
|
|---|
| 1973 | class="cmtt-8"> one</span><span
|
|---|
| 1974 | class="cmtt-8"> bit;</span><br class="fancyvrb" /><a
|
|---|
| 1975 | id="x1-51040r5"></a><span
|
|---|
| 1976 | class="cmr-6">5</span><span
|
|---|
| 1977 | class="cmtt-8"> </span><span
|
|---|
| 1978 | class="cmtt-8"> </span><span
|
|---|
| 1979 | class="cmtt-8"> </span><span
|
|---|
| 1980 | class="cmtt-8"> </span><span
|
|---|
| 1981 | class="cmtt-8"> </span><span
|
|---|
| 1982 | class="cmtt-8"> </span><span
|
|---|
| 1983 | class="cmtt-8"> </span><span
|
|---|
| 1984 | class="cmtt-8"> </span><span
|
|---|
| 1985 | class="cmtt-8"> 3)</span><span
|
|---|
| 1986 | class="cmtt-8"> if([flag]</span><span
|
|---|
| 1987 | class="cmtt-8"> is</span><span
|
|---|
| 1988 | class="cmtt-8"> set)</span><span
|
|---|
| 1989 | class="cmtt-8"> </span><span
|
|---|
| 1990 | class="cmsy-8">{</span><br class="fancyvrb" /><a
|
|---|
| 1991 | id="x1-51042r6"></a><span
|
|---|
| 1992 | class="cmr-6">6</span>
|
|---|
| 1993 | <br class="fancyvrb" /><a
|
|---|
| 1994 | id="x1-51044r7"></a><span
|
|---|
| 1995 | class="cmr-6">7</span><span
|
|---|
| 1996 | class="cmtt-8"> </span><span
|
|---|
| 1997 | class="cmtt-8"> </span><span
|
|---|
| 1998 | class="cmtt-8"> </span><span
|
|---|
| 1999 | class="cmtt-8"> </span><span
|
|---|
| 2000 | class="cmtt-8"> </span><span
|
|---|
| 2001 | class="cmtt-8"> </span><span
|
|---|
| 2002 | class="cmtt-8"> </span><span
|
|---|
| 2003 | class="cmtt-8"> </span><span
|
|---|
| 2004 | class="cmtt-8"> </span><span
|
|---|
| 2005 | class="cmtt-8"> </span><span
|
|---|
| 2006 | class="cmtt-8"> </span><span
|
|---|
| 2007 | class="cmtt-8"> </span><span
|
|---|
| 2008 | class="cmtt-8"> </span><span
|
|---|
| 2009 | class="cmtt-8"> 4)</span><span
|
|---|
| 2010 | class="cmtt-8"> [length]</span><span
|
|---|
| 2011 | class="cmtt-8"> =</span><span
|
|---|
| 2012 | class="cmtt-8"> read</span><span
|
|---|
| 2013 | class="cmtt-8"> a</span><span
|
|---|
| 2014 | class="cmtt-8"> five</span><span
|
|---|
| 2015 | class="cmtt-8"> bit</span><span
|
|---|
| 2016 | class="cmtt-8"> unsigned</span><span
|
|---|
| 2017 | class="cmtt-8"> integer;</span><br class="fancyvrb" /><a
|
|---|
| 2018 | id="x1-51046r8"></a><span
|
|---|
| 2019 | class="cmr-6">8</span><span
|
|---|
| 2020 | class="cmtt-8"> </span><span
|
|---|
| 2021 | class="cmtt-8"> </span><span
|
|---|
| 2022 | class="cmtt-8"> </span><span
|
|---|
| 2023 | class="cmtt-8"> </span><span
|
|---|
| 2024 | class="cmtt-8"> </span><span
|
|---|
| 2025 | class="cmtt-8"> </span><span
|
|---|
| 2026 | class="cmtt-8"> </span><span
|
|---|
| 2027 | class="cmtt-8"> </span><span
|
|---|
| 2028 | class="cmtt-8"> </span><span
|
|---|
| 2029 | class="cmtt-8"> </span><span
|
|---|
| 2030 | class="cmtt-8"> </span><span
|
|---|
| 2031 | class="cmtt-8"> </span><span
|
|---|
| 2032 | class="cmtt-8"> </span><span
|
|---|
| 2033 | class="cmtt-8"> 5)</span><span
|
|---|
| 2034 | class="cmtt-8"> codeword</span><span
|
|---|
| 2035 | class="cmtt-8"> length</span><span
|
|---|
| 2036 | class="cmtt-8"> for</span><span
|
|---|
| 2037 | class="cmtt-8"> this</span><span
|
|---|
| 2038 | class="cmtt-8"> entry</span><span
|
|---|
| 2039 | class="cmtt-8"> is</span><span
|
|---|
| 2040 | class="cmtt-8"> [length]+1;</span><br class="fancyvrb" /><a
|
|---|
| 2041 | id="x1-51048r9"></a><span
|
|---|
| 2042 | class="cmr-6">9</span>
|
|---|
| 2043 | <br class="fancyvrb" /><a
|
|---|
| 2044 | id="x1-51050r10"></a><span
|
|---|
| 2045 | class="cmr-6">10</span><span
|
|---|
| 2046 | class="cmtt-8"> </span><span
|
|---|
| 2047 | class="cmtt-8"> </span><span
|
|---|
| 2048 | class="cmtt-8"> </span><span
|
|---|
| 2049 | class="cmtt-8"> </span><span
|
|---|
| 2050 | class="cmtt-8"> </span><span
|
|---|
| 2051 | class="cmtt-8"> </span><span
|
|---|
| 2052 | class="cmtt-8"> </span><span
|
|---|
| 2053 | class="cmtt-8"> </span><span
|
|---|
| 2054 | class="cmtt-8"> </span><span
|
|---|
| 2055 | class="cmtt-8"> </span><span
|
|---|
| 2056 | class="cmtt-8"> </span><span
|
|---|
| 2057 | class="cmtt-8"> </span><span
|
|---|
| 2058 | class="cmsy-8">}</span><span
|
|---|
| 2059 | class="cmtt-8"> else</span><span
|
|---|
| 2060 | class="cmtt-8"> </span><span
|
|---|
| 2061 | class="cmsy-8">{</span><br class="fancyvrb" /><a
|
|---|
| 2062 | id="x1-51052r11"></a><span
|
|---|
| 2063 | class="cmr-6">11</span><br class="fancyvrb" /><a
|
|---|
| 2064 | id="x1-51054r12"></a><span
|
|---|
| 2065 | class="cmr-6">12</span><span
|
|---|
| 2066 | class="cmtt-8"> </span><span
|
|---|
| 2067 | class="cmtt-8"> </span><span
|
|---|
| 2068 | class="cmtt-8"> </span><span
|
|---|
| 2069 | class="cmtt-8"> </span><span
|
|---|
| 2070 | class="cmtt-8"> </span><span
|
|---|
| 2071 | class="cmtt-8"> </span><span
|
|---|
| 2072 | class="cmtt-8"> </span><span
|
|---|
| 2073 | class="cmtt-8"> </span><span
|
|---|
| 2074 | class="cmtt-8"> </span><span
|
|---|
| 2075 | class="cmtt-8"> </span><span
|
|---|
| 2076 | class="cmtt-8"> </span><span
|
|---|
| 2077 | class="cmtt-8"> </span><span
|
|---|
| 2078 | class="cmtt-8"> </span><span
|
|---|
| 2079 | class="cmtt-8"> 6)</span><span
|
|---|
| 2080 | class="cmtt-8"> this</span><span
|
|---|
| 2081 | class="cmtt-8"> entry</span><span
|
|---|
| 2082 | class="cmtt-8"> is</span><span
|
|---|
| 2083 | class="cmtt-8"> unused.</span><span
|
|---|
| 2084 | class="cmtt-8"> </span><span
|
|---|
| 2085 | class="cmtt-8"> mark</span><span
|
|---|
| 2086 | class="cmtt-8"> it</span><span
|
|---|
| 2087 | class="cmtt-8"> as</span><span
|
|---|
| 2088 | class="cmtt-8"> such.</span><br class="fancyvrb" /><a
|
|---|
| 2089 | id="x1-51056r13"></a><span
|
|---|
| 2090 | class="cmr-6">13</span><br class="fancyvrb" /><a
|
|---|
| 2091 | id="x1-51058r14"></a><span
|
|---|
| 2092 | class="cmr-6">14</span><span
|
|---|
| 2093 | class="cmtt-8"> </span><span
|
|---|
| 2094 | class="cmtt-8"> </span><span
|
|---|
| 2095 | class="cmtt-8"> </span><span
|
|---|
| 2096 | class="cmtt-8"> </span><span
|
|---|
| 2097 | class="cmtt-8"> </span><span
|
|---|
| 2098 | class="cmtt-8"> </span><span
|
|---|
| 2099 | class="cmtt-8"> </span><span
|
|---|
| 2100 | class="cmtt-8"> </span><span
|
|---|
| 2101 | class="cmtt-8"> </span><span
|
|---|
| 2102 | class="cmtt-8"> </span><span
|
|---|
| 2103 | class="cmtt-8"> </span><span
|
|---|
| 2104 | class="cmtt-8"> </span><span
|
|---|
| 2105 | class="cmsy-8">}</span><br class="fancyvrb" /><a
|
|---|
| 2106 | id="x1-51060r15"></a><span
|
|---|
| 2107 | class="cmr-6">15</span><br class="fancyvrb" /><a
|
|---|
| 2108 | id="x1-51062r16"></a><span
|
|---|
| 2109 | class="cmr-6">16</span><span
|
|---|
| 2110 | class="cmtt-8"> </span><span
|
|---|
| 2111 | class="cmtt-8"> </span><span
|
|---|
| 2112 | class="cmtt-8"> </span><span
|
|---|
| 2113 | class="cmtt-8"> </span><span
|
|---|
| 2114 | class="cmtt-8"> </span><span
|
|---|
| 2115 | class="cmsy-8">}</span><span
|
|---|
| 2116 | class="cmtt-8"> else</span><span
|
|---|
| 2117 | class="cmtt-8"> the</span><span
|
|---|
| 2118 | class="cmtt-8"> sparse</span><span
|
|---|
| 2119 | class="cmtt-8"> flag</span><span
|
|---|
| 2120 | class="cmtt-8"> is</span><span
|
|---|
| 2121 | class="cmtt-8"> not</span><span
|
|---|
| 2122 | class="cmtt-8"> set</span><span
|
|---|
| 2123 | class="cmtt-8"> </span><span
|
|---|
| 2124 | class="cmsy-8">{</span><br class="fancyvrb" /><a
|
|---|
| 2125 | id="x1-51064r17"></a><span
|
|---|
| 2126 | class="cmr-6">17</span>
|
|---|
| 2127 | <br class="fancyvrb" /><a
|
|---|
| 2128 | id="x1-51066r18"></a><span
|
|---|
| 2129 | class="cmr-6">18</span><span
|
|---|
| 2130 | class="cmtt-8"> </span><span
|
|---|
| 2131 | class="cmtt-8"> </span><span
|
|---|
| 2132 | class="cmtt-8"> </span><span
|
|---|
| 2133 | class="cmtt-8"> </span><span
|
|---|
| 2134 | class="cmtt-8"> </span><span
|
|---|
| 2135 | class="cmtt-8"> </span><span
|
|---|
| 2136 | class="cmtt-8"> </span><span
|
|---|
| 2137 | class="cmtt-8"> 7)</span><span
|
|---|
| 2138 | class="cmtt-8"> [length]</span><span
|
|---|
| 2139 | class="cmtt-8"> =</span><span
|
|---|
| 2140 | class="cmtt-8"> read</span><span
|
|---|
| 2141 | class="cmtt-8"> a</span><span
|
|---|
| 2142 | class="cmtt-8"> five</span><span
|
|---|
| 2143 | class="cmtt-8"> bit</span><span
|
|---|
| 2144 | class="cmtt-8"> unsigned</span><span
|
|---|
| 2145 | class="cmtt-8"> integer;</span><br class="fancyvrb" /><a
|
|---|
| 2146 | id="x1-51068r19"></a><span
|
|---|
| 2147 | class="cmr-6">19</span><span
|
|---|
| 2148 | class="cmtt-8"> </span><span
|
|---|
| 2149 | class="cmtt-8"> </span><span
|
|---|
| 2150 | class="cmtt-8"> </span><span
|
|---|
| 2151 | class="cmtt-8"> </span><span
|
|---|
| 2152 | class="cmtt-8"> </span><span
|
|---|
| 2153 | class="cmtt-8"> </span><span
|
|---|
| 2154 | class="cmtt-8"> </span><span
|
|---|
| 2155 | class="cmtt-8"> 8)</span><span
|
|---|
| 2156 | class="cmtt-8"> the</span><span
|
|---|
| 2157 | class="cmtt-8"> codeword</span><span
|
|---|
| 2158 | class="cmtt-8"> length</span><span
|
|---|
| 2159 | class="cmtt-8"> for</span><span
|
|---|
| 2160 | class="cmtt-8"> this</span><span
|
|---|
| 2161 | class="cmtt-8"> entry</span><span
|
|---|
| 2162 | class="cmtt-8"> is</span><span
|
|---|
| 2163 | class="cmtt-8"> [length]+1;</span><br class="fancyvrb" /><a
|
|---|
| 2164 | id="x1-51070r20"></a><span
|
|---|
| 2165 | class="cmr-6">20</span><br class="fancyvrb" /><a
|
|---|
| 2166 | id="x1-51072r21"></a><span
|
|---|
| 2167 | class="cmr-6">21</span><span
|
|---|
| 2168 | class="cmtt-8"> </span><span
|
|---|
| 2169 | class="cmtt-8"> </span><span
|
|---|
| 2170 | class="cmtt-8"> </span><span
|
|---|
| 2171 | class="cmtt-8"> </span><span
|
|---|
| 2172 | class="cmtt-8"> </span><span
|
|---|
| 2173 | class="cmsy-8">}</span><br class="fancyvrb" /><a
|
|---|
| 2174 | id="x1-51074r22"></a><span
|
|---|
| 2175 | class="cmr-6">22</span></div>
|
|---|
| 2176 |
|
|---|
| 2177 |
|
|---|
| 2178 |
|
|---|
| 2179 | </li>
|
|---|
| 2180 | <li class="itemize">If the <span
|
|---|
| 2181 | class="cmtt-12">[ordered] </span>flag is set, the codeword list for this codebook is encoded in
|
|---|
| 2182 | ascending length order. Rather than reading a length for every codeword, the
|
|---|
| 2183 | encoder reads the number of codewords per length. That is, beginning at entry
|
|---|
| 2184 | zero:
|
|---|
| 2185 | <!--l. 119--><p class="noindent" >
|
|---|
| 2186 | <div class="fancyvrb" id="fancyvrb12"><a
|
|---|
| 2187 | id="x1-51076r1"></a><span
|
|---|
| 2188 | class="cmr-6">1</span><span
|
|---|
| 2189 | class="cmtt-8"> </span><span
|
|---|
| 2190 | class="cmtt-8"> 1)</span><span
|
|---|
| 2191 | class="cmtt-8"> [current</span><span
|
|---|
| 2192 | class="cmtt-8">_entry]</span><span
|
|---|
| 2193 | class="cmtt-8"> =</span><span
|
|---|
| 2194 | class="cmtt-8"> 0;</span><br class="fancyvrb" /><a
|
|---|
| 2195 | id="x1-51078r2"></a><span
|
|---|
| 2196 | class="cmr-6">2</span><span
|
|---|
| 2197 | class="cmtt-8"> </span><span
|
|---|
| 2198 | class="cmtt-8"> 2)</span><span
|
|---|
| 2199 | class="cmtt-8"> [current</span><span
|
|---|
| 2200 | class="cmtt-8">_length]</span><span
|
|---|
| 2201 | class="cmtt-8"> =</span><span
|
|---|
| 2202 | class="cmtt-8"> read</span><span
|
|---|
| 2203 | class="cmtt-8"> a</span><span
|
|---|
| 2204 | class="cmtt-8"> five</span><span
|
|---|
| 2205 | class="cmtt-8"> bit</span><span
|
|---|
| 2206 | class="cmtt-8"> unsigned</span><span
|
|---|
| 2207 | class="cmtt-8"> integer</span><span
|
|---|
| 2208 | class="cmtt-8"> and</span><span
|
|---|
| 2209 | class="cmtt-8"> add</span><span
|
|---|
| 2210 | class="cmtt-8"> 1;</span>
|
|---|
| 2211 | <br class="fancyvrb" /><a
|
|---|
| 2212 | id="x1-51080r3"></a><span
|
|---|
| 2213 | class="cmr-6">3</span><span
|
|---|
| 2214 | class="cmtt-8"> </span><span
|
|---|
| 2215 | class="cmtt-8"> 3)</span><span
|
|---|
| 2216 | class="cmtt-8"> [number]</span><span
|
|---|
| 2217 | class="cmtt-8"> =</span><span
|
|---|
| 2218 | class="cmtt-8"> read</span><span
|
|---|
| 2219 | class="cmtt-8"> </span><a
|
|---|
| 2220 | href="#x1-1190009.2.1"><span
|
|---|
| 2221 | class="cmtt-8">ilog</span></a><span
|
|---|
| 2222 | class="cmtt-8">([codebook</span><span
|
|---|
| 2223 | class="cmtt-8">_entries]</span><span
|
|---|
| 2224 | class="cmtt-8"> -</span><span
|
|---|
| 2225 | class="cmtt-8"> [current</span><span
|
|---|
| 2226 | class="cmtt-8">_entry])</span><span
|
|---|
| 2227 | class="cmtt-8"> bits</span><span
|
|---|
| 2228 | class="cmtt-8"> as</span><span
|
|---|
| 2229 | class="cmtt-8"> an</span><span
|
|---|
| 2230 | class="cmtt-8"> unsigned</span><span
|
|---|
| 2231 | class="cmtt-8"> integer</span>
|
|---|
| 2232 | <br class="fancyvrb" /><a
|
|---|
| 2233 | id="x1-51082r4"></a><span
|
|---|
| 2234 | class="cmr-6">4</span><span
|
|---|
| 2235 | class="cmtt-8"> </span><span
|
|---|
| 2236 | class="cmtt-8"> 4)</span><span
|
|---|
| 2237 | class="cmtt-8"> set</span><span
|
|---|
| 2238 | class="cmtt-8"> the</span><span
|
|---|
| 2239 | class="cmtt-8"> entries</span><span
|
|---|
| 2240 | class="cmtt-8"> [current</span><span
|
|---|
| 2241 | class="cmtt-8">_entry]</span><span
|
|---|
| 2242 | class="cmtt-8"> through</span><span
|
|---|
| 2243 | class="cmtt-8"> [current</span><span
|
|---|
| 2244 | class="cmtt-8">_entry]+[number]-1,</span><span
|
|---|
| 2245 | class="cmtt-8"> inclusive,</span>
|
|---|
| 2246 | <br class="fancyvrb" /><a
|
|---|
| 2247 | id="x1-51084r5"></a><span
|
|---|
| 2248 | class="cmr-6">5</span><span
|
|---|
| 2249 | class="cmtt-8"> </span><span
|
|---|
| 2250 | class="cmtt-8"> </span><span
|
|---|
| 2251 | class="cmtt-8"> </span><span
|
|---|
| 2252 | class="cmtt-8"> of</span><span
|
|---|
| 2253 | class="cmtt-8"> the</span><span
|
|---|
| 2254 | class="cmtt-8"> [codebook</span><span
|
|---|
| 2255 | class="cmtt-8">_codeword</span><span
|
|---|
| 2256 | class="cmtt-8">_lengths]</span><span
|
|---|
| 2257 | class="cmtt-8"> array</span><span
|
|---|
| 2258 | class="cmtt-8"> to</span><span
|
|---|
| 2259 | class="cmtt-8"> [current</span><span
|
|---|
| 2260 | class="cmtt-8">_length]</span><br class="fancyvrb" /><a
|
|---|
| 2261 | id="x1-51086r6"></a><span
|
|---|
| 2262 | class="cmr-6">6</span><span
|
|---|
| 2263 | class="cmtt-8"> </span><span
|
|---|
| 2264 | class="cmtt-8"> 5)</span><span
|
|---|
| 2265 | class="cmtt-8"> set</span><span
|
|---|
| 2266 | class="cmtt-8"> [current</span><span
|
|---|
| 2267 | class="cmtt-8">_entry]</span><span
|
|---|
| 2268 | class="cmtt-8"> to</span><span
|
|---|
| 2269 | class="cmtt-8"> [number]</span><span
|
|---|
| 2270 | class="cmtt-8"> +</span><span
|
|---|
| 2271 | class="cmtt-8"> [current</span><span
|
|---|
| 2272 | class="cmtt-8">_entry]</span>
|
|---|
| 2273 | <br class="fancyvrb" /><a
|
|---|
| 2274 | id="x1-51088r7"></a><span
|
|---|
| 2275 | class="cmr-6">7</span><span
|
|---|
| 2276 | class="cmtt-8"> </span><span
|
|---|
| 2277 | class="cmtt-8"> 6)</span><span
|
|---|
| 2278 | class="cmtt-8"> increment</span><span
|
|---|
| 2279 | class="cmtt-8"> [current</span><span
|
|---|
| 2280 | class="cmtt-8">_length]</span><span
|
|---|
| 2281 | class="cmtt-8"> by</span><span
|
|---|
| 2282 | class="cmtt-8"> 1</span><br class="fancyvrb" /><a
|
|---|
| 2283 | id="x1-51090r8"></a><span
|
|---|
| 2284 | class="cmr-6">8</span><span
|
|---|
| 2285 | class="cmtt-8"> </span><span
|
|---|
| 2286 | class="cmtt-8"> 7)</span><span
|
|---|
| 2287 | class="cmtt-8"> if</span><span
|
|---|
| 2288 | class="cmtt-8"> [current</span><span
|
|---|
| 2289 | class="cmtt-8">_entry]</span><span
|
|---|
| 2290 | class="cmtt-8"> is</span><span
|
|---|
| 2291 | class="cmtt-8"> greater</span><span
|
|---|
| 2292 | class="cmtt-8"> than</span><span
|
|---|
| 2293 | class="cmtt-8"> [codebook</span><span
|
|---|
| 2294 | class="cmtt-8">_entries]</span><span
|
|---|
| 2295 | class="cmtt-8"> ERROR</span><span
|
|---|
| 2296 | class="cmtt-8"> CONDITION;</span>
|
|---|
| 2297 | <br class="fancyvrb" /><a
|
|---|
| 2298 | id="x1-51092r9"></a><span
|
|---|
| 2299 | class="cmr-6">9</span><span
|
|---|
| 2300 | class="cmtt-8"> </span><span
|
|---|
| 2301 | class="cmtt-8"> </span><span
|
|---|
| 2302 | class="cmtt-8"> </span><span
|
|---|
| 2303 | class="cmtt-8"> the</span><span
|
|---|
| 2304 | class="cmtt-8"> decoder</span><span
|
|---|
| 2305 | class="cmtt-8"> will</span><span
|
|---|
| 2306 | class="cmtt-8"> not</span><span
|
|---|
| 2307 | class="cmtt-8"> be</span><span
|
|---|
| 2308 | class="cmtt-8"> able</span><span
|
|---|
| 2309 | class="cmtt-8"> to</span><span
|
|---|
| 2310 | class="cmtt-8"> read</span><span
|
|---|
| 2311 | class="cmtt-8"> this</span><span
|
|---|
| 2312 | class="cmtt-8"> stream.</span><br class="fancyvrb" /><a
|
|---|
| 2313 | id="x1-51094r10"></a><span
|
|---|
| 2314 | class="cmr-6">10</span><span
|
|---|
| 2315 | class="cmtt-8"> </span><span
|
|---|
| 2316 | class="cmtt-8"> 8)</span><span
|
|---|
| 2317 | class="cmtt-8"> if</span><span
|
|---|
| 2318 | class="cmtt-8"> [current</span><span
|
|---|
| 2319 | class="cmtt-8">_entry]</span><span
|
|---|
| 2320 | class="cmtt-8"> is</span><span
|
|---|
| 2321 | class="cmtt-8"> less</span><span
|
|---|
| 2322 | class="cmtt-8"> than</span><span
|
|---|
| 2323 | class="cmtt-8"> [codebook</span><span
|
|---|
| 2324 | class="cmtt-8">_entries],</span><span
|
|---|
| 2325 | class="cmtt-8"> repeat</span><span
|
|---|
| 2326 | class="cmtt-8"> process</span><span
|
|---|
| 2327 | class="cmtt-8"> starting</span><span
|
|---|
| 2328 | class="cmtt-8"> at</span><span
|
|---|
| 2329 | class="cmtt-8"> 3)</span>
|
|---|
| 2330 | <br class="fancyvrb" /><a
|
|---|
| 2331 | id="x1-51096r11"></a><span
|
|---|
| 2332 | class="cmr-6">11</span><span
|
|---|
| 2333 | class="cmtt-8"> </span><span
|
|---|
| 2334 | class="cmtt-8"> 9)</span><span
|
|---|
| 2335 | class="cmtt-8"> done.</span></div>
|
|---|
| 2336 | </li></ul>
|
|---|
| 2337 | <!--l. 135--><p class="noindent" >After all codeword lengths have been decoded, the decoder reads the vector lookup table. Vorbis
|
|---|
| 2338 | I supports three lookup types:
|
|---|
| 2339 | <dl class="enumerate-enumitem"><dt class="enumerate-enumitem">
|
|---|
| 2340 | 1. </dt><dd
|
|---|
| 2341 | class="enumerate-enumitem">No lookup
|
|---|
| 2342 | </dd><dt class="enumerate-enumitem">
|
|---|
| 2343 | 2. </dt><dd
|
|---|
| 2344 | class="enumerate-enumitem">Implicitly populated value mapping (lattice VQ)
|
|---|
| 2345 | </dd><dt class="enumerate-enumitem">
|
|---|
| 2346 | 3. </dt><dd
|
|---|
| 2347 | class="enumerate-enumitem">Explicitly populated value mapping (tessellated or ’foam’ VQ)</dd></dl>
|
|---|
| 2348 | <!--l. 148--><p class="noindent" >The lookup table type is read as a four bit unsigned integer:
|
|---|
| 2349 | <div class="fancyvrb" id="fancyvrb13"><a
|
|---|
| 2350 | id="x1-51101r1"></a><span
|
|---|
| 2351 | class="cmr-6">1</span><span
|
|---|
| 2352 | class="cmtt-8"> </span><span
|
|---|
| 2353 | class="cmtt-8"> 1)</span><span
|
|---|
| 2354 | class="cmtt-8"> [codebook</span><span
|
|---|
| 2355 | class="cmtt-8">_lookup</span><span
|
|---|
| 2356 | class="cmtt-8">_type]</span><span
|
|---|
| 2357 | class="cmtt-8"> =</span><span
|
|---|
| 2358 | class="cmtt-8"> read</span><span
|
|---|
| 2359 | class="cmtt-8"> four</span><span
|
|---|
| 2360 | class="cmtt-8"> bits</span><span
|
|---|
| 2361 | class="cmtt-8"> as</span><span
|
|---|
| 2362 | class="cmtt-8"> an</span><span
|
|---|
| 2363 | class="cmtt-8"> unsigned</span><span
|
|---|
| 2364 | class="cmtt-8"> integer</span></div>
|
|---|
| 2365 | <!--l. 153--><p class="noindent" >Codebook decode precedes according to <span
|
|---|
| 2366 | class="cmtt-12">[codebook</span><span
|
|---|
| 2367 | class="cmtt-12">_lookup</span><span
|
|---|
| 2368 | class="cmtt-12">_type]</span>:
|
|---|
| 2369 | <ul class="itemize1">
|
|---|
| 2370 | <li class="itemize">Lookup type zero indicates no lookup to be read. Proceed past lookup decode.
|
|---|
| 2371 | </li>
|
|---|
| 2372 | <li class="itemize">Lookup types one and two are similar, differing only in the number of lookup values to
|
|---|
| 2373 | be read. Lookup type one reads a list of values that are permuted in a set pattern to
|
|---|
| 2374 | build a list of vectors, each vector of order <span
|
|---|
| 2375 | class="cmtt-12">[codebook</span><span
|
|---|
| 2376 | class="cmtt-12">_dimensions] </span>scalars. Lookup
|
|---|
| 2377 | type two builds the same vector list, but reads each scalar for each vector explicitly,
|
|---|
| 2378 | rather than building vectors from a smaller list of possible scalar values. Lookup
|
|---|
| 2379 | decode proceeds as follows:
|
|---|
| 2380 | <!--l. 167--><p class="noindent" >
|
|---|
| 2381 | <div class="fancyvrb" id="fancyvrb14"><a
|
|---|
| 2382 | id="x1-51103r1"></a><span
|
|---|
| 2383 | class="cmr-6">1</span><span
|
|---|
| 2384 | class="cmtt-8"> </span><span
|
|---|
| 2385 | class="cmtt-8"> 1)</span><span
|
|---|
| 2386 | class="cmtt-8"> [codebook</span><span
|
|---|
| 2387 | class="cmtt-8">_minimum</span><span
|
|---|
| 2388 | class="cmtt-8">_value]</span><span
|
|---|
| 2389 | class="cmtt-8"> =</span><span
|
|---|
| 2390 | class="cmtt-8"> </span><a
|
|---|
| 2391 | href="#x1-1200009.2.2"><span
|
|---|
| 2392 | class="cmtt-8">float32</span><span
|
|---|
| 2393 | class="cmtt-8">_unpack</span></a><span
|
|---|
| 2394 | class="cmtt-8">(</span><span
|
|---|
| 2395 | class="cmtt-8"> read</span><span
|
|---|
| 2396 | class="cmtt-8"> 32</span><span
|
|---|
| 2397 | class="cmtt-8"> bits</span><span
|
|---|
| 2398 | class="cmtt-8"> as</span><span
|
|---|
| 2399 | class="cmtt-8"> an</span><span
|
|---|
| 2400 | class="cmtt-8"> unsigned</span><span
|
|---|
| 2401 | class="cmtt-8"> integer)</span>
|
|---|
| 2402 | <br class="fancyvrb" /><a
|
|---|
| 2403 | id="x1-51105r2"></a><span
|
|---|
| 2404 | class="cmr-6">2</span><span
|
|---|
| 2405 | class="cmtt-8"> </span><span
|
|---|
| 2406 | class="cmtt-8"> 2)</span><span
|
|---|
| 2407 | class="cmtt-8"> [codebook</span><span
|
|---|
| 2408 | class="cmtt-8">_delta</span><span
|
|---|
| 2409 | class="cmtt-8">_value]</span><span
|
|---|
| 2410 | class="cmtt-8"> =</span><span
|
|---|
| 2411 | class="cmtt-8"> </span><a
|
|---|
| 2412 | href="#x1-1200009.2.2"><span
|
|---|
| 2413 | class="cmtt-8">float32</span><span
|
|---|
| 2414 | class="cmtt-8">_unpack</span></a><span
|
|---|
| 2415 | class="cmtt-8">(</span><span
|
|---|
| 2416 | class="cmtt-8"> read</span><span
|
|---|
| 2417 | class="cmtt-8"> 32</span><span
|
|---|
| 2418 | class="cmtt-8"> bits</span><span
|
|---|
| 2419 | class="cmtt-8"> as</span><span
|
|---|
| 2420 | class="cmtt-8"> an</span><span
|
|---|
| 2421 | class="cmtt-8"> unsigned</span><span
|
|---|
| 2422 | class="cmtt-8"> integer)</span>
|
|---|
| 2423 | <br class="fancyvrb" /><a
|
|---|
| 2424 | id="x1-51107r3"></a><span
|
|---|
| 2425 | class="cmr-6">3</span><span
|
|---|
| 2426 | class="cmtt-8"> </span><span
|
|---|
| 2427 | class="cmtt-8"> 3)</span><span
|
|---|
| 2428 | class="cmtt-8"> [codebook</span><span
|
|---|
| 2429 | class="cmtt-8">_value</span><span
|
|---|
| 2430 | class="cmtt-8">_bits]</span><span
|
|---|
| 2431 | class="cmtt-8"> =</span><span
|
|---|
| 2432 | class="cmtt-8"> read</span><span
|
|---|
| 2433 | class="cmtt-8"> 4</span><span
|
|---|
| 2434 | class="cmtt-8"> bits</span><span
|
|---|
| 2435 | class="cmtt-8"> as</span><span
|
|---|
| 2436 | class="cmtt-8"> an</span><span
|
|---|
| 2437 | class="cmtt-8"> unsigned</span><span
|
|---|
| 2438 | class="cmtt-8"> integer</span><span
|
|---|
| 2439 | class="cmtt-8"> and</span><span
|
|---|
| 2440 | class="cmtt-8"> add</span><span
|
|---|
| 2441 | class="cmtt-8"> 1</span><br class="fancyvrb" /><a
|
|---|
| 2442 | id="x1-51109r4"></a><span
|
|---|
| 2443 | class="cmr-6">4</span><span
|
|---|
| 2444 | class="cmtt-8"> </span><span
|
|---|
| 2445 | class="cmtt-8"> 4)</span><span
|
|---|
| 2446 | class="cmtt-8"> [codebook</span><span
|
|---|
| 2447 | class="cmtt-8">_sequence</span><span
|
|---|
| 2448 | class="cmtt-8">_p]</span><span
|
|---|
| 2449 | class="cmtt-8"> =</span><span
|
|---|
| 2450 | class="cmtt-8"> read</span><span
|
|---|
| 2451 | class="cmtt-8"> 1</span><span
|
|---|
| 2452 | class="cmtt-8"> bit</span><span
|
|---|
| 2453 | class="cmtt-8"> as</span><span
|
|---|
| 2454 | class="cmtt-8"> a</span><span
|
|---|
| 2455 | class="cmtt-8"> boolean</span><span
|
|---|
| 2456 | class="cmtt-8"> flag</span><br class="fancyvrb" /><a
|
|---|
| 2457 | id="x1-51111r5"></a><span
|
|---|
| 2458 | class="cmr-6">5</span>
|
|---|
| 2459 |
|
|---|
| 2460 |
|
|---|
| 2461 |
|
|---|
| 2462 | <br class="fancyvrb" /><a
|
|---|
| 2463 | id="x1-51113r6"></a><span
|
|---|
| 2464 | class="cmr-6">6</span><span
|
|---|
| 2465 | class="cmtt-8"> </span><span
|
|---|
| 2466 | class="cmtt-8"> if</span><span
|
|---|
| 2467 | class="cmtt-8"> (</span><span
|
|---|
| 2468 | class="cmtt-8"> [codebook</span><span
|
|---|
| 2469 | class="cmtt-8">_lookup</span><span
|
|---|
| 2470 | class="cmtt-8">_type]</span><span
|
|---|
| 2471 | class="cmtt-8"> is</span><span
|
|---|
| 2472 | class="cmtt-8"> 1</span><span
|
|---|
| 2473 | class="cmtt-8"> )</span><span
|
|---|
| 2474 | class="cmtt-8"> </span><span
|
|---|
| 2475 | class="cmsy-8">{</span><br class="fancyvrb" /><a
|
|---|
| 2476 | id="x1-51115r7"></a><span
|
|---|
| 2477 | class="cmr-6">7</span><br class="fancyvrb" /><a
|
|---|
| 2478 | id="x1-51117r8"></a><span
|
|---|
| 2479 | class="cmr-6">8</span><span
|
|---|
| 2480 | class="cmtt-8"> </span><span
|
|---|
| 2481 | class="cmtt-8"> </span><span
|
|---|
| 2482 | class="cmtt-8"> </span><span
|
|---|
| 2483 | class="cmtt-8"> </span><span
|
|---|
| 2484 | class="cmtt-8"> 5)</span><span
|
|---|
| 2485 | class="cmtt-8"> [codebook</span><span
|
|---|
| 2486 | class="cmtt-8">_lookup</span><span
|
|---|
| 2487 | class="cmtt-8">_values]</span><span
|
|---|
| 2488 | class="cmtt-8"> =</span><span
|
|---|
| 2489 | class="cmtt-8"> </span><a
|
|---|
| 2490 | href="#x1-1210009.2.3"><span
|
|---|
| 2491 | class="cmtt-8">lookup1</span><span
|
|---|
| 2492 | class="cmtt-8">_values</span></a><span
|
|---|
| 2493 | class="cmtt-8">([codebook</span><span
|
|---|
| 2494 | class="cmtt-8">_entries],</span><span
|
|---|
| 2495 | class="cmtt-8"> [codebook</span><span
|
|---|
| 2496 | class="cmtt-8">_dimensions]</span><span
|
|---|
| 2497 | class="cmtt-8"> )</span><br class="fancyvrb" /><a
|
|---|
| 2498 | id="x1-51119r9"></a><span
|
|---|
| 2499 | class="cmr-6">9</span>
|
|---|
| 2500 | <br class="fancyvrb" /><a
|
|---|
| 2501 | id="x1-51121r10"></a><span
|
|---|
| 2502 | class="cmr-6">10</span><span
|
|---|
| 2503 | class="cmtt-8"> </span><span
|
|---|
| 2504 | class="cmtt-8"> </span><span
|
|---|
| 2505 | class="cmsy-8">}</span><span
|
|---|
| 2506 | class="cmtt-8"> else</span><span
|
|---|
| 2507 | class="cmtt-8"> </span><span
|
|---|
| 2508 | class="cmsy-8">{</span><br class="fancyvrb" /><a
|
|---|
| 2509 | id="x1-51123r11"></a><span
|
|---|
| 2510 | class="cmr-6">11</span><br class="fancyvrb" /><a
|
|---|
| 2511 | id="x1-51125r12"></a><span
|
|---|
| 2512 | class="cmr-6">12</span><span
|
|---|
| 2513 | class="cmtt-8"> </span><span
|
|---|
| 2514 | class="cmtt-8"> </span><span
|
|---|
| 2515 | class="cmtt-8"> </span><span
|
|---|
| 2516 | class="cmtt-8"> </span><span
|
|---|
| 2517 | class="cmtt-8"> 6)</span><span
|
|---|
| 2518 | class="cmtt-8"> [codebook</span><span
|
|---|
| 2519 | class="cmtt-8">_lookup</span><span
|
|---|
| 2520 | class="cmtt-8">_values]</span><span
|
|---|
| 2521 | class="cmtt-8"> =</span><span
|
|---|
| 2522 | class="cmtt-8"> [codebook</span><span
|
|---|
| 2523 | class="cmtt-8">_entries]</span><span
|
|---|
| 2524 | class="cmtt-8"> *</span><span
|
|---|
| 2525 | class="cmtt-8"> [codebook</span><span
|
|---|
| 2526 | class="cmtt-8">_dimensions]</span><br class="fancyvrb" /><a
|
|---|
| 2527 | id="x1-51127r13"></a><span
|
|---|
| 2528 | class="cmr-6">13</span><br class="fancyvrb" /><a
|
|---|
| 2529 | id="x1-51129r14"></a><span
|
|---|
| 2530 | class="cmr-6">14</span><span
|
|---|
| 2531 | class="cmtt-8"> </span><span
|
|---|
| 2532 | class="cmtt-8"> </span><span
|
|---|
| 2533 | class="cmsy-8">}</span><br class="fancyvrb" /><a
|
|---|
| 2534 | id="x1-51131r15"></a><span
|
|---|
| 2535 | class="cmr-6">15</span>
|
|---|
| 2536 | <br class="fancyvrb" /><a
|
|---|
| 2537 | id="x1-51133r16"></a><span
|
|---|
| 2538 | class="cmr-6">16</span><span
|
|---|
| 2539 | class="cmtt-8"> </span><span
|
|---|
| 2540 | class="cmtt-8"> 7)</span><span
|
|---|
| 2541 | class="cmtt-8"> read</span><span
|
|---|
| 2542 | class="cmtt-8"> a</span><span
|
|---|
| 2543 | class="cmtt-8"> total</span><span
|
|---|
| 2544 | class="cmtt-8"> of</span><span
|
|---|
| 2545 | class="cmtt-8"> [codebook</span><span
|
|---|
| 2546 | class="cmtt-8">_lookup</span><span
|
|---|
| 2547 | class="cmtt-8">_values]</span><span
|
|---|
| 2548 | class="cmtt-8"> unsigned</span><span
|
|---|
| 2549 | class="cmtt-8"> integers</span><span
|
|---|
| 2550 | class="cmtt-8"> of</span><span
|
|---|
| 2551 | class="cmtt-8"> [codebook</span><span
|
|---|
| 2552 | class="cmtt-8">_value</span><span
|
|---|
| 2553 | class="cmtt-8">_bits]</span><span
|
|---|
| 2554 | class="cmtt-8"> each;</span>
|
|---|
| 2555 | <br class="fancyvrb" /><a
|
|---|
| 2556 | id="x1-51135r17"></a><span
|
|---|
| 2557 | class="cmr-6">17</span><span
|
|---|
| 2558 | class="cmtt-8"> </span><span
|
|---|
| 2559 | class="cmtt-8"> </span><span
|
|---|
| 2560 | class="cmtt-8"> </span><span
|
|---|
| 2561 | class="cmtt-8"> </span><span
|
|---|
| 2562 | class="cmtt-8"> store</span><span
|
|---|
| 2563 | class="cmtt-8"> these</span><span
|
|---|
| 2564 | class="cmtt-8"> in</span><span
|
|---|
| 2565 | class="cmtt-8"> order</span><span
|
|---|
| 2566 | class="cmtt-8"> in</span><span
|
|---|
| 2567 | class="cmtt-8"> the</span><span
|
|---|
| 2568 | class="cmtt-8"> array</span><span
|
|---|
| 2569 | class="cmtt-8"> [codebook</span><span
|
|---|
| 2570 | class="cmtt-8">_multiplicands]</span></div>
|
|---|
| 2571 | </li>
|
|---|
| 2572 | <li class="itemize">A <span
|
|---|
| 2573 | class="cmtt-12">[codebook</span><span
|
|---|
| 2574 | class="cmtt-12">_lookup</span><span
|
|---|
| 2575 | class="cmtt-12">_type] </span>of greater than two is reserved and indicates a stream that is
|
|---|
| 2576 | not decodable by the specification in this document.
|
|---|
| 2577 | </li></ul>
|
|---|
| 2578 | <!--l. 194--><p class="noindent" >An ’end of packet’ during any read operation in the above steps is considered an error condition
|
|---|
| 2579 | rendering the stream undecodable.
|
|---|
| 2580 | <!--l. 197--><p class="noindent" ><span class="paragraphHead"><a
|
|---|
| 2581 | id="x1-520003.2.1"></a><span
|
|---|
| 2582 | class="cmbx-12">Huffman decision tree representation</span></span>
|
|---|
| 2583 | The <span
|
|---|
| 2584 | class="cmtt-12">[codebook</span><span
|
|---|
| 2585 | class="cmtt-12">_codeword</span><span
|
|---|
| 2586 | class="cmtt-12">_lengths] </span>array and <span
|
|---|
| 2587 | class="cmtt-12">[codebook</span><span
|
|---|
| 2588 | class="cmtt-12">_entries] </span>value uniquely define the
|
|---|
| 2589 | Huffman decision tree used for entropy decoding.
|
|---|
| 2590 | <!--l. 203--><p class="noindent" >Briefly, each used codebook entry (recall that length-unordered codebooks support unused
|
|---|
| 2591 | codeword entries) is assigned, in order, the lowest valued unused binary Huffman codeword
|
|---|
| 2592 | possible. Assume the following codeword length list:
|
|---|
| 2593 | <!--l. 208--><p class="noindent" >
|
|---|
| 2594 | <div class="fancyvrb" id="fancyvrb15"><a
|
|---|
| 2595 | id="x1-52002r1"></a><span
|
|---|
| 2596 | class="cmr-6">1</span><span
|
|---|
| 2597 | class="cmtt-8">entry</span><span
|
|---|
| 2598 | class="cmtt-8"> 0:</span><span
|
|---|
| 2599 | class="cmtt-8"> length</span><span
|
|---|
| 2600 | class="cmtt-8"> 2</span><br class="fancyvrb" /><a
|
|---|
| 2601 | id="x1-52004r2"></a><span
|
|---|
| 2602 | class="cmr-6">2</span><span
|
|---|
| 2603 | class="cmtt-8">entry</span><span
|
|---|
| 2604 | class="cmtt-8"> 1:</span><span
|
|---|
| 2605 | class="cmtt-8"> length</span><span
|
|---|
| 2606 | class="cmtt-8"> 4</span><br class="fancyvrb" /><a
|
|---|
| 2607 | id="x1-52006r3"></a><span
|
|---|
| 2608 | class="cmr-6">3</span><span
|
|---|
| 2609 | class="cmtt-8">entry</span><span
|
|---|
| 2610 | class="cmtt-8"> 2:</span><span
|
|---|
| 2611 | class="cmtt-8"> length</span><span
|
|---|
| 2612 | class="cmtt-8"> 4</span><br class="fancyvrb" /><a
|
|---|
| 2613 | id="x1-52008r4"></a><span
|
|---|
| 2614 | class="cmr-6">4</span><span
|
|---|
| 2615 | class="cmtt-8">entry</span><span
|
|---|
| 2616 | class="cmtt-8"> 3:</span><span
|
|---|
| 2617 | class="cmtt-8"> length</span><span
|
|---|
| 2618 | class="cmtt-8"> 4</span><br class="fancyvrb" /><a
|
|---|
| 2619 | id="x1-52010r5"></a><span
|
|---|
| 2620 | class="cmr-6">5</span><span
|
|---|
| 2621 | class="cmtt-8">entry</span><span
|
|---|
| 2622 | class="cmtt-8"> 4:</span><span
|
|---|
| 2623 | class="cmtt-8"> length</span><span
|
|---|
| 2624 | class="cmtt-8"> 4</span><br class="fancyvrb" /><a
|
|---|
| 2625 | id="x1-52012r6"></a><span
|
|---|
| 2626 | class="cmr-6">6</span><span
|
|---|
| 2627 | class="cmtt-8">entry</span><span
|
|---|
| 2628 | class="cmtt-8"> 5:</span><span
|
|---|
| 2629 | class="cmtt-8"> length</span><span
|
|---|
| 2630 | class="cmtt-8"> 2</span><br class="fancyvrb" /><a
|
|---|
| 2631 | id="x1-52014r7"></a><span
|
|---|
| 2632 | class="cmr-6">7</span><span
|
|---|
| 2633 | class="cmtt-8">entry</span><span
|
|---|
| 2634 | class="cmtt-8"> 6:</span><span
|
|---|
| 2635 | class="cmtt-8"> length</span><span
|
|---|
| 2636 | class="cmtt-8"> 3</span><br class="fancyvrb" /><a
|
|---|
| 2637 | id="x1-52016r8"></a><span
|
|---|
| 2638 | class="cmr-6">8</span><span
|
|---|
| 2639 | class="cmtt-8">entry</span><span
|
|---|
| 2640 | class="cmtt-8"> 7:</span><span
|
|---|
| 2641 | class="cmtt-8"> length</span><span
|
|---|
| 2642 | class="cmtt-8"> 3</span></div>
|
|---|
| 2643 | <!--l. 219--><p class="noindent" >Assigning codewords in order (lowest possible value of the appropriate length to highest) results
|
|---|
| 2644 | in the following codeword list:
|
|---|
| 2645 | <!--l. 222--><p class="noindent" >
|
|---|
| 2646 | <div class="fancyvrb" id="fancyvrb16"><a
|
|---|
| 2647 | id="x1-52018r1"></a><span
|
|---|
| 2648 | class="cmr-6">1</span><span
|
|---|
| 2649 | class="cmtt-8">entry</span><span
|
|---|
| 2650 | class="cmtt-8"> 0:</span><span
|
|---|
| 2651 | class="cmtt-8"> length</span><span
|
|---|
| 2652 | class="cmtt-8"> 2</span><span
|
|---|
| 2653 | class="cmtt-8"> codeword</span><span
|
|---|
| 2654 | class="cmtt-8"> 00</span><br class="fancyvrb" /><a
|
|---|
| 2655 | id="x1-52020r2"></a><span
|
|---|
| 2656 | class="cmr-6">2</span><span
|
|---|
| 2657 | class="cmtt-8">entry</span><span
|
|---|
| 2658 | class="cmtt-8"> 1:</span><span
|
|---|
| 2659 | class="cmtt-8"> length</span><span
|
|---|
| 2660 | class="cmtt-8"> 4</span><span
|
|---|
| 2661 | class="cmtt-8"> codeword</span><span
|
|---|
| 2662 | class="cmtt-8"> 0100</span><br class="fancyvrb" /><a
|
|---|
| 2663 | id="x1-52022r3"></a><span
|
|---|
| 2664 | class="cmr-6">3</span><span
|
|---|
| 2665 | class="cmtt-8">entry</span><span
|
|---|
| 2666 | class="cmtt-8"> 2:</span><span
|
|---|
| 2667 | class="cmtt-8"> length</span><span
|
|---|
| 2668 | class="cmtt-8"> 4</span><span
|
|---|
| 2669 | class="cmtt-8"> codeword</span><span
|
|---|
| 2670 | class="cmtt-8"> 0101</span><br class="fancyvrb" /><a
|
|---|
| 2671 | id="x1-52024r4"></a><span
|
|---|
| 2672 | class="cmr-6">4</span><span
|
|---|
| 2673 | class="cmtt-8">entry</span><span
|
|---|
| 2674 | class="cmtt-8"> 3:</span><span
|
|---|
| 2675 | class="cmtt-8"> length</span><span
|
|---|
| 2676 | class="cmtt-8"> 4</span><span
|
|---|
| 2677 | class="cmtt-8"> codeword</span><span
|
|---|
| 2678 | class="cmtt-8"> 0110</span>
|
|---|
| 2679 | <br class="fancyvrb" /><a
|
|---|
| 2680 | id="x1-52026r5"></a><span
|
|---|
| 2681 | class="cmr-6">5</span><span
|
|---|
| 2682 | class="cmtt-8">entry</span><span
|
|---|
| 2683 | class="cmtt-8"> 4:</span><span
|
|---|
| 2684 | class="cmtt-8"> length</span><span
|
|---|
| 2685 | class="cmtt-8"> 4</span><span
|
|---|
| 2686 | class="cmtt-8"> codeword</span><span
|
|---|
| 2687 | class="cmtt-8"> 0111</span><br class="fancyvrb" /><a
|
|---|
| 2688 | id="x1-52028r6"></a><span
|
|---|
| 2689 | class="cmr-6">6</span><span
|
|---|
| 2690 | class="cmtt-8">entry</span><span
|
|---|
| 2691 | class="cmtt-8"> 5:</span><span
|
|---|
| 2692 | class="cmtt-8"> length</span><span
|
|---|
| 2693 | class="cmtt-8"> 2</span><span
|
|---|
| 2694 | class="cmtt-8"> codeword</span><span
|
|---|
| 2695 | class="cmtt-8"> 10</span><br class="fancyvrb" /><a
|
|---|
| 2696 | id="x1-52030r7"></a><span
|
|---|
| 2697 | class="cmr-6">7</span><span
|
|---|
| 2698 | class="cmtt-8">entry</span><span
|
|---|
| 2699 | class="cmtt-8"> 6:</span><span
|
|---|
| 2700 | class="cmtt-8"> length</span><span
|
|---|
| 2701 | class="cmtt-8"> 3</span><span
|
|---|
| 2702 | class="cmtt-8"> codeword</span><span
|
|---|
| 2703 | class="cmtt-8"> 110</span><br class="fancyvrb" /><a
|
|---|
| 2704 | id="x1-52032r8"></a><span
|
|---|
| 2705 | class="cmr-6">8</span><span
|
|---|
| 2706 | class="cmtt-8">entry</span><span
|
|---|
| 2707 | class="cmtt-8"> 7:</span><span
|
|---|
| 2708 | class="cmtt-8"> length</span><span
|
|---|
| 2709 | class="cmtt-8"> 3</span><span
|
|---|
| 2710 | class="cmtt-8"> codeword</span><span
|
|---|
| 2711 | class="cmtt-8"> 111</span></div>
|
|---|
| 2712 | <!--l. 234--><p class="noindent" ><span class="likesubparagraphHead"><a
|
|---|
| 2713 | id="x1-530003.2.1"></a><span
|
|---|
| 2714 | class="cmbx-12">Note:</span></span> Unlike most binary numerical values in this document, we intend the above codewords to
|
|---|
| 2715 | be read and used bit by bit from left to right, thus the codeword ’001’ is the bit string ’zero, zero,
|
|---|
| 2716 | one’. When determining ’lowest possible value’ in the assignment definition above, the leftmost
|
|---|
| 2717 | bit is the MSb.
|
|---|
| 2718 | <!--l. 242--><p class="noindent" >It is clear that the codeword length list represents a Huffman decision tree with the entry
|
|---|
| 2719 | numbers equivalent to the leaves numbered left-to-right:
|
|---|
| 2720 |
|
|---|
| 2721 |
|
|---|
| 2722 |
|
|---|
| 2723 | <div class="center"
|
|---|
| 2724 | >
|
|---|
| 2725 | <!--l. 246--><p class="noindent" >
|
|---|
| 2726 |
|
|---|
| 2727 | <!--l. 247--><p class="noindent" ><img
|
|---|
| 2728 | src="hufftree.png" alt="PIC"
|
|---|
| 2729 | >
|
|---|
| 2730 | <br /> <div class="caption"
|
|---|
| 2731 | ><span class="id">Figure 4: </span><span
|
|---|
| 2732 | class="content">huffman tree illustration</span></div><!--tex4ht:label?: x1-530014 -->
|
|---|
| 2733 | </div>
|
|---|
| 2734 | <!--l. 252--><p class="noindent" >As we assign codewords in order, we see that each choice constructs a new leaf in the leftmost
|
|---|
| 2735 | possible position.
|
|---|
| 2736 | <!--l. 255--><p class="noindent" >Note that it’s possible to underspecify or overspecify a Huffman tree via the length list.
|
|---|
| 2737 | In the above example, if codeword seven were eliminated, it’s clear that the tree is
|
|---|
| 2738 | unfinished:
|
|---|
| 2739 | <div class="center"
|
|---|
| 2740 | >
|
|---|
| 2741 | <!--l. 259--><p class="noindent" >
|
|---|
| 2742 |
|
|---|
| 2743 | <!--l. 260--><p class="noindent" ><img
|
|---|
| 2744 | src="hufftree-under.png" alt="PIC"
|
|---|
| 2745 | >
|
|---|
| 2746 | <br /> <div class="caption"
|
|---|
| 2747 | ><span class="id">Figure 5: </span><span
|
|---|
| 2748 | class="content">underspecified huffman tree illustration</span></div><!--tex4ht:label?: x1-530025 -->
|
|---|
| 2749 | </div>
|
|---|
| 2750 | <!--l. 265--><p class="noindent" >Similarly, in the original codebook, it’s clear that the tree is fully populated and a ninth
|
|---|
| 2751 | codeword is impossible. Both underspecified and overspecified trees are an error condition
|
|---|
| 2752 | rendering the stream undecodable.
|
|---|
| 2753 | <!--l. 270--><p class="noindent" >Codebook entries marked ’unused’ are simply skipped in the assigning process. They have no
|
|---|
| 2754 | codeword and do not appear in the decision tree, thus it’s impossible for any bit pattern read
|
|---|
| 2755 | from the stream to decode to that entry number.
|
|---|
| 2756 | <!--l. 275--><p class="noindent" ><span class="paragraphHead"><a
|
|---|
| 2757 | id="x1-540003.2.1"></a><span
|
|---|
| 2758 | class="cmbx-12">Errata 20150226: Single entry codebooks</span></span>
|
|---|
| 2759 | A ’single-entry codebook’ is a codebook with one active codeword entry. A single-entry codebook
|
|---|
| 2760 | may be either a fully populated codebook with only one declared entry, or a sparse codebook
|
|---|
| 2761 | with only one entry marked used. The Vorbis I spec provides no means to specify a codeword
|
|---|
| 2762 | length of zero, and as a result, a single-entry codebook is inherently malformed because it is
|
|---|
| 2763 | underpopulated. The original specification did not address directly the matter of single-entry
|
|---|
| 2764 | codebooks; they were implicitly illegal as it was not possible to write such a codebook with a
|
|---|
| 2765 | valid tree structure.
|
|---|
| 2766 |
|
|---|
| 2767 |
|
|---|
| 2768 |
|
|---|
| 2769 | <!--l. 287--><p class="noindent" >In r14811 of the libvorbis reference implementation, Xiph added an additional check to the
|
|---|
| 2770 | codebook implementation to reject underpopulated Huffman trees. This change led to the
|
|---|
| 2771 | discovery of single-entry books used ’in the wild’ when the new, stricter checks rejected a number
|
|---|
| 2772 | of apparently working streams.
|
|---|
| 2773 | <!--l. 293--><p class="noindent" >In order to minimize breakage of deployed (if technically erroneous) streams, r16073 of the
|
|---|
| 2774 | reference implementation explicitly special-cased single-entry codebooks to tolerate the
|
|---|
| 2775 | single-entry case. Commit r16073 also added the following to the specification:
|
|---|
| 2776 | <!--l. 302--><p class="noindent" >“<span class="sout">Take special care that a codebook with a single used entry is handled properly; it consists of a
|
|---|
| 2777 | single codework of zero bits and reading a value out of such a codebook always returns the single
|
|---|
| 2778 | used value and sinks zero bits. </span>”
|
|---|
| 2779 | <!--l. 304--><p class="noindent" >The intent was to clarify the spec and codify current practice. However, this addition is
|
|---|
| 2780 | erroneously at odds with the intent of preserving usability of existing streams using single-entry
|
|---|
| 2781 | codebooks, disagrees with the code changes that reinstated decoding, and does not address how
|
|---|
| 2782 | single-entry codebooks should be encoded.
|
|---|
| 2783 | <!--l. 310--><p class="noindent" >As such, the above addition made in r16037 is struck from the specification and replaced by the
|
|---|
| 2784 | following:
|
|---|
| 2785 | <!--l. 329--><p class="noindent" >
|
|---|
| 2786 | <div class="quote">
|
|---|
| 2787 | <!--l. 329--><p class="noindent" >It is possible to declare a Vorbis codebook containing a single codework
|
|---|
| 2788 | entry. A single-entry codebook may be either a fully populated codebook with
|
|---|
| 2789 | <span
|
|---|
| 2790 | class="cmtt-12">[codebook</span><span
|
|---|
| 2791 | class="cmtt-12">_entries] </span>set to 1, or a sparse codebook marking only one entry
|
|---|
| 2792 | used. Note that it is not possible to also encode a <span
|
|---|
| 2793 | class="cmtt-12">[codeword</span><span
|
|---|
| 2794 | class="cmtt-12">_length] </span>of zero
|
|---|
| 2795 | for the single used codeword, as the unsigned value written to the stream
|
|---|
| 2796 | is <span
|
|---|
| 2797 | class="cmtt-12">[codeword</span><span
|
|---|
| 2798 | class="cmtt-12">_length]-1</span>. Instead, encoder implementations should indicate a
|
|---|
| 2799 | <span
|
|---|
| 2800 | class="cmtt-12">[codeword</span><span
|
|---|
| 2801 | class="cmtt-12">_length] </span>of 1 and ’write’ the codeword to a stream during audio
|
|---|
| 2802 | encoding by writing a single zero bit.
|
|---|
| 2803 | <!--l. 329--><p class="noindent" >Decoder implementations shall reject a codebook if it contains only one used
|
|---|
| 2804 | entry and the encoded <span
|
|---|
| 2805 | class="cmtt-12">[codeword</span><span
|
|---|
| 2806 | class="cmtt-12">_length] </span>of that entry is not 1. ’Reading’ a
|
|---|
| 2807 | value from single-entry codebook always returns the single used codeword value
|
|---|
| 2808 | and sinks one bit. Decoders should tolerate that the bit read from the stream
|
|---|
| 2809 | be ’1’ instead of ’0’; both values shall return the single used codeword.</div>
|
|---|
| 2810 | <!--l. 331--><p class="noindent" ><span class="paragraphHead"><a
|
|---|
| 2811 | id="x1-550003.2.1"></a><span
|
|---|
| 2812 | class="cmbx-12">VQ lookup table vector representation</span></span>
|
|---|
| 2813 | Unpacking the VQ lookup table vectors relies on the following values:
|
|---|
| 2814 |
|
|---|
| 2815 |
|
|---|
| 2816 |
|
|---|
| 2817 | <div class="fancyvrb" id="fancyvrb17"><a
|
|---|
| 2818 | id="x1-55002r1"></a><span
|
|---|
| 2819 | class="cmr-6">1</span><span
|
|---|
| 2820 | class="cmtt-8">the</span><span
|
|---|
| 2821 | class="cmtt-8"> [codebook\_multiplicands]</span><span
|
|---|
| 2822 | class="cmtt-8"> array</span><br class="fancyvrb" /><a
|
|---|
| 2823 | id="x1-55004r2"></a><span
|
|---|
| 2824 | class="cmr-6">2</span><span
|
|---|
| 2825 | class="cmtt-8">[codebook\_minimum\_value]</span><br class="fancyvrb" /><a
|
|---|
| 2826 | id="x1-55006r3"></a><span
|
|---|
| 2827 | class="cmr-6">3</span><span
|
|---|
| 2828 | class="cmtt-8">[codebook\_delta\_value]</span><br class="fancyvrb" /><a
|
|---|
| 2829 | id="x1-55008r4"></a><span
|
|---|
| 2830 | class="cmr-6">4</span><span
|
|---|
| 2831 | class="cmtt-8">[codebook\_sequence\_p]</span>
|
|---|
| 2832 | <br class="fancyvrb" /><a
|
|---|
| 2833 | id="x1-55010r5"></a><span
|
|---|
| 2834 | class="cmr-6">5</span><span
|
|---|
| 2835 | class="cmtt-8">[codebook\_lookup\_type]</span><br class="fancyvrb" /><a
|
|---|
| 2836 | id="x1-55012r6"></a><span
|
|---|
| 2837 | class="cmr-6">6</span><span
|
|---|
| 2838 | class="cmtt-8">[codebook\_entries]</span><br class="fancyvrb" /><a
|
|---|
| 2839 | id="x1-55014r7"></a><span
|
|---|
| 2840 | class="cmr-6">7</span><span
|
|---|
| 2841 | class="cmtt-8">[codebook\_dimensions]</span><br class="fancyvrb" /><a
|
|---|
| 2842 | id="x1-55016r8"></a><span
|
|---|
| 2843 | class="cmr-6">8</span><span
|
|---|
| 2844 | class="cmtt-8">[codebook\_lookup\_values]</span></div>
|
|---|
| 2845 | <!--l. 347--><p class="noindent" >Decoding (unpacking) a specific vector in the vector lookup table proceeds according to
|
|---|
| 2846 | <span
|
|---|
| 2847 | class="cmtt-12">[codebook</span><span
|
|---|
| 2848 | class="cmtt-12">_lookup</span><span
|
|---|
| 2849 | class="cmtt-12">_type]</span>. The unpacked vector values are what a codebook would return
|
|---|
| 2850 | during audio packet decode in a VQ context.
|
|---|
| 2851 | <!--l. 352--><p class="noindent" ><span class="paragraphHead"><a
|
|---|
| 2852 | id="x1-560003.2.1"></a><span
|
|---|
| 2853 | class="cmbx-12">Vector value decode: Lookup type 1</span></span>
|
|---|
| 2854 | Lookup type one specifies a lattice VQ lookup table built algorithmically from a list of
|
|---|
| 2855 | scalar values. Calculate (unpack) the final values of a codebook entry vector from
|
|---|
| 2856 | the entries in <span
|
|---|
| 2857 | class="cmtt-12">[codebook</span><span
|
|---|
| 2858 | class="cmtt-12">_multiplicands] </span>as follows (<span
|
|---|
| 2859 | class="cmtt-12">[value</span><span
|
|---|
| 2860 | class="cmtt-12">_vector] </span>is the output
|
|---|
| 2861 | vector representing the vector of values for entry number <span
|
|---|
| 2862 | class="cmtt-12">[lookup</span><span
|
|---|
| 2863 | class="cmtt-12">_offset] </span>in this
|
|---|
| 2864 | codebook):
|
|---|
| 2865 | <!--l. 361--><p class="noindent" >
|
|---|
| 2866 | <div class="fancyvrb" id="fancyvrb18"><a
|
|---|
| 2867 | id="x1-56002r1"></a><span
|
|---|
| 2868 | class="cmr-6">1</span><span
|
|---|
| 2869 | class="cmtt-8"> </span><span
|
|---|
| 2870 | class="cmtt-8"> 1)</span><span
|
|---|
| 2871 | class="cmtt-8"> [last]</span><span
|
|---|
| 2872 | class="cmtt-8"> =</span><span
|
|---|
| 2873 | class="cmtt-8"> 0;</span><br class="fancyvrb" /><a
|
|---|
| 2874 | id="x1-56004r2"></a><span
|
|---|
| 2875 | class="cmr-6">2</span><span
|
|---|
| 2876 | class="cmtt-8"> </span><span
|
|---|
| 2877 | class="cmtt-8"> 2)</span><span
|
|---|
| 2878 | class="cmtt-8"> [index</span><span
|
|---|
| 2879 | class="cmtt-8">_divisor]</span><span
|
|---|
| 2880 | class="cmtt-8"> =</span><span
|
|---|
| 2881 | class="cmtt-8"> 1;</span><br class="fancyvrb" /><a
|
|---|
| 2882 | id="x1-56006r3"></a><span
|
|---|
| 2883 | class="cmr-6">3</span><span
|
|---|
| 2884 | class="cmtt-8"> </span><span
|
|---|
| 2885 | class="cmtt-8"> 3)</span><span
|
|---|
| 2886 | class="cmtt-8"> iterate</span><span
|
|---|
| 2887 | class="cmtt-8"> [i]</span><span
|
|---|
| 2888 | class="cmtt-8"> over</span><span
|
|---|
| 2889 | class="cmtt-8"> the</span><span
|
|---|
| 2890 | class="cmtt-8"> range</span><span
|
|---|
| 2891 | class="cmtt-8"> 0</span><span
|
|---|
| 2892 | class="cmtt-8"> ...</span><span
|
|---|
| 2893 | class="cmtt-8"> [codebook</span><span
|
|---|
| 2894 | class="cmtt-8">_dimensions]-1</span><span
|
|---|
| 2895 | class="cmtt-8"> (once</span><span
|
|---|
| 2896 | class="cmtt-8"> for</span><span
|
|---|
| 2897 | class="cmtt-8"> each</span><span
|
|---|
| 2898 | class="cmtt-8"> scalar</span><span
|
|---|
| 2899 | class="cmtt-8"> value</span><span
|
|---|
| 2900 | class="cmtt-8"> in</span><span
|
|---|
| 2901 | class="cmtt-8"> the</span><span
|
|---|
| 2902 | class="cmtt-8"> value</span><span
|
|---|
| 2903 | class="cmtt-8"> vector)</span><span
|
|---|
| 2904 | class="cmtt-8"> </span><span
|
|---|
| 2905 | class="cmsy-8">{</span><br class="fancyvrb" /><a
|
|---|
| 2906 | id="x1-56008r4"></a><span
|
|---|
| 2907 | class="cmr-6">4</span>
|
|---|
| 2908 | <br class="fancyvrb" /><a
|
|---|
| 2909 | id="x1-56010r5"></a><span
|
|---|
| 2910 | class="cmr-6">5</span><span
|
|---|
| 2911 | class="cmtt-8"> </span><span
|
|---|
| 2912 | class="cmtt-8"> </span><span
|
|---|
| 2913 | class="cmtt-8"> </span><span
|
|---|
| 2914 | class="cmtt-8"> </span><span
|
|---|
| 2915 | class="cmtt-8"> </span><span
|
|---|
| 2916 | class="cmtt-8"> </span><span
|
|---|
| 2917 | class="cmtt-8"> 4)</span><span
|
|---|
| 2918 | class="cmtt-8"> [multiplicand</span><span
|
|---|
| 2919 | class="cmtt-8">_offset]</span><span
|
|---|
| 2920 | class="cmtt-8"> =</span><span
|
|---|
| 2921 | class="cmtt-8"> (</span><span
|
|---|
| 2922 | class="cmtt-8"> [lookup</span><span
|
|---|
| 2923 | class="cmtt-8">_offset]</span><span
|
|---|
| 2924 | class="cmtt-8"> divided</span><span
|
|---|
| 2925 | class="cmtt-8"> by</span><span
|
|---|
| 2926 | class="cmtt-8"> [index</span><span
|
|---|
| 2927 | class="cmtt-8">_divisor]</span><span
|
|---|
| 2928 | class="cmtt-8"> using</span><span
|
|---|
| 2929 | class="cmtt-8"> integer</span>
|
|---|
| 2930 | <br class="fancyvrb" /><a
|
|---|
| 2931 | id="x1-56012r6"></a><span
|
|---|
| 2932 | class="cmr-6">6</span><span
|
|---|
| 2933 | class="cmtt-8"> </span><span
|
|---|
| 2934 | class="cmtt-8"> </span><span
|
|---|
| 2935 | class="cmtt-8"> </span><span
|
|---|
| 2936 | class="cmtt-8"> </span><span
|
|---|
| 2937 | class="cmtt-8"> </span><span
|
|---|
| 2938 | class="cmtt-8"> </span><span
|
|---|
| 2939 | class="cmtt-8"> </span><span
|
|---|
| 2940 | class="cmtt-8"> </span><span
|
|---|
| 2941 | class="cmtt-8"> </span><span
|
|---|
| 2942 | class="cmtt-8"> division</span><span
|
|---|
| 2943 | class="cmtt-8"> )</span><span
|
|---|
| 2944 | class="cmtt-8"> integer</span><span
|
|---|
| 2945 | class="cmtt-8"> modulo</span><span
|
|---|
| 2946 | class="cmtt-8"> [codebook</span><span
|
|---|
| 2947 | class="cmtt-8">_lookup</span><span
|
|---|
| 2948 | class="cmtt-8">_values]</span><br class="fancyvrb" /><a
|
|---|
| 2949 | id="x1-56014r7"></a><span
|
|---|
| 2950 | class="cmr-6">7</span><br class="fancyvrb" /><a
|
|---|
| 2951 | id="x1-56016r8"></a><span
|
|---|
| 2952 | class="cmr-6">8</span><span
|
|---|
| 2953 | class="cmtt-8"> </span><span
|
|---|
| 2954 | class="cmtt-8"> </span><span
|
|---|
| 2955 | class="cmtt-8"> </span><span
|
|---|
| 2956 | class="cmtt-8"> </span><span
|
|---|
| 2957 | class="cmtt-8"> </span><span
|
|---|
| 2958 | class="cmtt-8"> </span><span
|
|---|
| 2959 | class="cmtt-8"> 5)</span><span
|
|---|
| 2960 | class="cmtt-8"> vector</span><span
|
|---|
| 2961 | class="cmtt-8"> [value</span><span
|
|---|
| 2962 | class="cmtt-8">_vector]</span><span
|
|---|
| 2963 | class="cmtt-8"> element</span><span
|
|---|
| 2964 | class="cmtt-8"> [i]</span><span
|
|---|
| 2965 | class="cmtt-8"> =</span>
|
|---|
| 2966 | <br class="fancyvrb" /><a
|
|---|
| 2967 | id="x1-56018r9"></a><span
|
|---|
| 2968 | class="cmr-6">9</span><span
|
|---|
| 2969 | class="cmtt-8"> </span><span
|
|---|
| 2970 | class="cmtt-8"> </span><span
|
|---|
| 2971 | class="cmtt-8"> </span><span
|
|---|
| 2972 | class="cmtt-8"> </span><span
|
|---|
| 2973 | class="cmtt-8"> </span><span
|
|---|
| 2974 | class="cmtt-8"> </span><span
|
|---|
| 2975 | class="cmtt-8"> </span><span
|
|---|
| 2976 | class="cmtt-8"> </span><span
|
|---|
| 2977 | class="cmtt-8"> </span><span
|
|---|
| 2978 | class="cmtt-8"> </span><span
|
|---|
| 2979 | class="cmtt-8"> </span><span
|
|---|
| 2980 | class="cmtt-8"> (</span><span
|
|---|
| 2981 | class="cmtt-8"> [codebook</span><span
|
|---|
| 2982 | class="cmtt-8">_multiplicands]</span><span
|
|---|
| 2983 | class="cmtt-8"> array</span><span
|
|---|
| 2984 | class="cmtt-8"> element</span><span
|
|---|
| 2985 | class="cmtt-8"> number</span><span
|
|---|
| 2986 | class="cmtt-8"> [multiplicand</span><span
|
|---|
| 2987 | class="cmtt-8">_offset]</span><span
|
|---|
| 2988 | class="cmtt-8"> )</span><span
|
|---|
| 2989 | class="cmtt-8"> *</span>
|
|---|
| 2990 | <br class="fancyvrb" /><a
|
|---|
| 2991 | id="x1-56020r10"></a><span
|
|---|
| 2992 | class="cmr-6">10</span><span
|
|---|
| 2993 | class="cmtt-8"> </span><span
|
|---|
| 2994 | class="cmtt-8"> </span><span
|
|---|
| 2995 | class="cmtt-8"> </span><span
|
|---|
| 2996 | class="cmtt-8"> </span><span
|
|---|
| 2997 | class="cmtt-8"> </span><span
|
|---|
| 2998 | class="cmtt-8"> </span><span
|
|---|
| 2999 | class="cmtt-8"> </span><span
|
|---|
| 3000 | class="cmtt-8"> </span><span
|
|---|
| 3001 | class="cmtt-8"> </span><span
|
|---|
| 3002 | class="cmtt-8"> </span><span
|
|---|
| 3003 | class="cmtt-8"> </span><span
|
|---|
| 3004 | class="cmtt-8"> [codebook</span><span
|
|---|
| 3005 | class="cmtt-8">_delta</span><span
|
|---|
| 3006 | class="cmtt-8">_value]</span><span
|
|---|
| 3007 | class="cmtt-8"> +</span><span
|
|---|
| 3008 | class="cmtt-8"> [codebook</span><span
|
|---|
| 3009 | class="cmtt-8">_minimum</span><span
|
|---|
| 3010 | class="cmtt-8">_value]</span><span
|
|---|
| 3011 | class="cmtt-8"> +</span><span
|
|---|
| 3012 | class="cmtt-8"> [last];</span><br class="fancyvrb" /><a
|
|---|
| 3013 | id="x1-56022r11"></a><span
|
|---|
| 3014 | class="cmr-6">11</span>
|
|---|
| 3015 | <br class="fancyvrb" /><a
|
|---|
| 3016 | id="x1-56024r12"></a><span
|
|---|
| 3017 | class="cmr-6">12</span><span
|
|---|
| 3018 | class="cmtt-8"> </span><span
|
|---|
| 3019 | class="cmtt-8"> </span><span
|
|---|
| 3020 | class="cmtt-8"> </span><span
|
|---|
| 3021 | class="cmtt-8"> </span><span
|
|---|
| 3022 | class="cmtt-8"> </span><span
|
|---|
| 3023 | class="cmtt-8"> </span><span
|
|---|
| 3024 | class="cmtt-8"> 6)</span><span
|
|---|
| 3025 | class="cmtt-8"> if</span><span
|
|---|
| 3026 | class="cmtt-8"> (</span><span
|
|---|
| 3027 | class="cmtt-8"> [codebook</span><span
|
|---|
| 3028 | class="cmtt-8">_sequence</span><span
|
|---|
| 3029 | class="cmtt-8">_p]</span><span
|
|---|
| 3030 | class="cmtt-8"> is</span><span
|
|---|
| 3031 | class="cmtt-8"> set</span><span
|
|---|
| 3032 | class="cmtt-8"> )</span><span
|
|---|
| 3033 | class="cmtt-8"> then</span><span
|
|---|
| 3034 | class="cmtt-8"> set</span><span
|
|---|
| 3035 | class="cmtt-8"> [last]</span><span
|
|---|
| 3036 | class="cmtt-8"> =</span><span
|
|---|
| 3037 | class="cmtt-8"> vector</span><span
|
|---|
| 3038 | class="cmtt-8"> [value</span><span
|
|---|
| 3039 | class="cmtt-8">_vector]</span><span
|
|---|
| 3040 | class="cmtt-8"> element</span><span
|
|---|
| 3041 | class="cmtt-8"> [i]</span><br class="fancyvrb" /><a
|
|---|
| 3042 | id="x1-56026r13"></a><span
|
|---|
| 3043 | class="cmr-6">13</span>
|
|---|
| 3044 | <br class="fancyvrb" /><a
|
|---|
| 3045 | id="x1-56028r14"></a><span
|
|---|
| 3046 | class="cmr-6">14</span><span
|
|---|
| 3047 | class="cmtt-8"> </span><span
|
|---|
| 3048 | class="cmtt-8"> </span><span
|
|---|
| 3049 | class="cmtt-8"> </span><span
|
|---|
| 3050 | class="cmtt-8"> </span><span
|
|---|
| 3051 | class="cmtt-8"> </span><span
|
|---|
| 3052 | class="cmtt-8"> </span><span
|
|---|
| 3053 | class="cmtt-8"> 7)</span><span
|
|---|
| 3054 | class="cmtt-8"> [index</span><span
|
|---|
| 3055 | class="cmtt-8">_divisor]</span><span
|
|---|
| 3056 | class="cmtt-8"> =</span><span
|
|---|
| 3057 | class="cmtt-8"> [index</span><span
|
|---|
| 3058 | class="cmtt-8">_divisor]</span><span
|
|---|
| 3059 | class="cmtt-8"> *</span><span
|
|---|
| 3060 | class="cmtt-8"> [codebook</span><span
|
|---|
| 3061 | class="cmtt-8">_lookup</span><span
|
|---|
| 3062 | class="cmtt-8">_values]</span><br class="fancyvrb" /><a
|
|---|
| 3063 | id="x1-56030r15"></a><span
|
|---|
| 3064 | class="cmr-6">15</span><br class="fancyvrb" /><a
|
|---|
| 3065 | id="x1-56032r16"></a><span
|
|---|
| 3066 | class="cmr-6">16</span><span
|
|---|
| 3067 | class="cmtt-8"> </span><span
|
|---|
| 3068 | class="cmtt-8"> </span><span
|
|---|
| 3069 | class="cmtt-8"> </span><span
|
|---|
| 3070 | class="cmtt-8"> </span><span
|
|---|
| 3071 | class="cmtt-8"> </span><span
|
|---|
| 3072 | class="cmsy-8">}</span><br class="fancyvrb" /><a
|
|---|
| 3073 | id="x1-56034r17"></a><span
|
|---|
| 3074 | class="cmr-6">17</span><br class="fancyvrb" /><a
|
|---|
| 3075 | id="x1-56036r18"></a><span
|
|---|
| 3076 | class="cmr-6">18</span><span
|
|---|
| 3077 | class="cmtt-8"> </span><span
|
|---|
| 3078 | class="cmtt-8"> 8)</span><span
|
|---|
| 3079 | class="cmtt-8"> vector</span><span
|
|---|
| 3080 | class="cmtt-8"> calculation</span><span
|
|---|
| 3081 | class="cmtt-8"> completed.</span></div>
|
|---|
| 3082 | <!--l. 384--><p class="noindent" ><span class="paragraphHead"><a
|
|---|
| 3083 | id="x1-570003.2.1"></a><span
|
|---|
| 3084 | class="cmbx-12">Vector value decode: Lookup type 2</span></span>
|
|---|
| 3085 | Lookup type two specifies a VQ lookup table in which each scalar in each vector is explicitly set
|
|---|
| 3086 | by the <span
|
|---|
| 3087 | class="cmtt-12">[codebook</span><span
|
|---|
| 3088 | class="cmtt-12">_multiplicands] </span>array in a one-to-one mapping. Calculate [unpack] the final
|
|---|
| 3089 | values of a codebook entry vector from the entries in <span
|
|---|
| 3090 | class="cmtt-12">[codebook</span><span
|
|---|
| 3091 | class="cmtt-12">_multiplicands] </span>as follows
|
|---|
| 3092 | (<span
|
|---|
| 3093 | class="cmtt-12">[value</span><span
|
|---|
| 3094 | class="cmtt-12">_vector] </span>is the output vector representing the vector of values for entry number
|
|---|
| 3095 | <span
|
|---|
| 3096 | class="cmtt-12">[lookup</span><span
|
|---|
| 3097 | class="cmtt-12">_offset] </span>in this codebook):
|
|---|
| 3098 | <!--l. 394--><p class="noindent" >
|
|---|
| 3099 | <div class="fancyvrb" id="fancyvrb19"><a
|
|---|
| 3100 | id="x1-57002r1"></a><span
|
|---|
| 3101 | class="cmr-6">1</span><span
|
|---|
| 3102 | class="cmtt-8"> </span><span
|
|---|
| 3103 | class="cmtt-8"> 1)</span><span
|
|---|
| 3104 | class="cmtt-8"> [last]</span><span
|
|---|
| 3105 | class="cmtt-8"> =</span><span
|
|---|
| 3106 | class="cmtt-8"> 0;</span><br class="fancyvrb" /><a
|
|---|
| 3107 | id="x1-57004r2"></a><span
|
|---|
| 3108 | class="cmr-6">2</span><span
|
|---|
| 3109 | class="cmtt-8"> </span><span
|
|---|
| 3110 | class="cmtt-8"> 2)</span><span
|
|---|
| 3111 | class="cmtt-8"> [multiplicand</span><span
|
|---|
| 3112 | class="cmtt-8">_offset]</span><span
|
|---|
| 3113 | class="cmtt-8"> =</span><span
|
|---|
| 3114 | class="cmtt-8"> [lookup</span><span
|
|---|
| 3115 | class="cmtt-8">_offset]</span><span
|
|---|
| 3116 | class="cmtt-8"> *</span><span
|
|---|
| 3117 | class="cmtt-8"> [codebook</span><span
|
|---|
| 3118 | class="cmtt-8">_dimensions]</span>
|
|---|
| 3119 | <br class="fancyvrb" /><a
|
|---|
| 3120 | id="x1-57006r3"></a><span
|
|---|
| 3121 | class="cmr-6">3</span><span
|
|---|
| 3122 | class="cmtt-8"> </span><span
|
|---|
| 3123 | class="cmtt-8"> 3)</span><span
|
|---|
| 3124 | class="cmtt-8"> iterate</span><span
|
|---|
| 3125 | class="cmtt-8"> [i]</span><span
|
|---|
| 3126 | class="cmtt-8"> over</span><span
|
|---|
| 3127 | class="cmtt-8"> the</span><span
|
|---|
| 3128 | class="cmtt-8"> range</span><span
|
|---|
| 3129 | class="cmtt-8"> 0</span><span
|
|---|
| 3130 | class="cmtt-8"> ...</span><span
|
|---|
| 3131 | class="cmtt-8"> [codebook</span><span
|
|---|
| 3132 | class="cmtt-8">_dimensions]-1</span><span
|
|---|
| 3133 | class="cmtt-8"> (once</span><span
|
|---|
| 3134 | class="cmtt-8"> for</span><span
|
|---|
| 3135 | class="cmtt-8"> each</span><span
|
|---|
| 3136 | class="cmtt-8"> scalar</span><span
|
|---|
| 3137 | class="cmtt-8"> value</span><span
|
|---|
| 3138 | class="cmtt-8"> in</span><span
|
|---|
| 3139 | class="cmtt-8"> the</span><span
|
|---|
| 3140 | class="cmtt-8"> value</span><span
|
|---|
| 3141 | class="cmtt-8"> vector)</span><span
|
|---|
| 3142 | class="cmtt-8"> </span><span
|
|---|
| 3143 | class="cmsy-8">{</span><br class="fancyvrb" /><a
|
|---|
| 3144 | id="x1-57008r4"></a><span
|
|---|
| 3145 | class="cmr-6">4</span>
|
|---|
| 3146 | <br class="fancyvrb" /><a
|
|---|
| 3147 | id="x1-57010r5"></a><span
|
|---|
| 3148 | class="cmr-6">5</span><span
|
|---|
| 3149 | class="cmtt-8"> </span><span
|
|---|
| 3150 | class="cmtt-8"> </span><span
|
|---|
| 3151 | class="cmtt-8"> </span><span
|
|---|
| 3152 | class="cmtt-8"> </span><span
|
|---|
| 3153 | class="cmtt-8"> </span><span
|
|---|
| 3154 | class="cmtt-8"> </span><span
|
|---|
| 3155 | class="cmtt-8"> 4)</span><span
|
|---|
| 3156 | class="cmtt-8"> vector</span><span
|
|---|
| 3157 | class="cmtt-8"> [value</span><span
|
|---|
| 3158 | class="cmtt-8">_vector]</span><span
|
|---|
| 3159 | class="cmtt-8"> element</span><span
|
|---|
| 3160 | class="cmtt-8"> [i]</span><span
|
|---|
| 3161 | class="cmtt-8"> =</span><br class="fancyvrb" /><a
|
|---|
| 3162 | id="x1-57012r6"></a><span
|
|---|
| 3163 | class="cmr-6">6</span><span
|
|---|
| 3164 | class="cmtt-8"> </span><span
|
|---|
| 3165 | class="cmtt-8"> </span><span
|
|---|
| 3166 | class="cmtt-8"> </span><span
|
|---|
| 3167 | class="cmtt-8"> </span><span
|
|---|
| 3168 | class="cmtt-8"> </span><span
|
|---|
| 3169 | class="cmtt-8"> </span><span
|
|---|
| 3170 | class="cmtt-8"> </span><span
|
|---|
| 3171 | class="cmtt-8"> </span><span
|
|---|
| 3172 | class="cmtt-8"> </span><span
|
|---|
| 3173 | class="cmtt-8"> </span><span
|
|---|
| 3174 | class="cmtt-8"> </span><span
|
|---|
| 3175 | class="cmtt-8"> (</span><span
|
|---|
| 3176 | class="cmtt-8"> [codebook</span><span
|
|---|
| 3177 | class="cmtt-8">_multiplicands]</span><span
|
|---|
| 3178 | class="cmtt-8"> array</span><span
|
|---|
| 3179 | class="cmtt-8"> element</span><span
|
|---|
| 3180 | class="cmtt-8"> number</span><span
|
|---|
| 3181 | class="cmtt-8"> [multiplicand</span><span
|
|---|
| 3182 | class="cmtt-8">_offset]</span><span
|
|---|
| 3183 | class="cmtt-8"> )</span><span
|
|---|
| 3184 | class="cmtt-8"> *</span>
|
|---|
| 3185 | <br class="fancyvrb" /><a
|
|---|
| 3186 | id="x1-57014r7"></a><span
|
|---|
| 3187 | class="cmr-6">7</span><span
|
|---|
| 3188 | class="cmtt-8"> </span><span
|
|---|
| 3189 | class="cmtt-8"> </span><span
|
|---|
| 3190 | class="cmtt-8"> </span><span
|
|---|
| 3191 | class="cmtt-8"> </span><span
|
|---|
| 3192 | class="cmtt-8"> </span><span
|
|---|
| 3193 | class="cmtt-8"> </span><span
|
|---|
| 3194 | class="cmtt-8"> </span><span
|
|---|
| 3195 | class="cmtt-8"> </span><span
|
|---|
| 3196 | class="cmtt-8"> </span><span
|
|---|
| 3197 | class="cmtt-8"> </span><span
|
|---|
| 3198 | class="cmtt-8"> </span><span
|
|---|
| 3199 | class="cmtt-8"> [codebook</span><span
|
|---|
| 3200 | class="cmtt-8">_delta</span><span
|
|---|
| 3201 | class="cmtt-8">_value]</span><span
|
|---|
| 3202 | class="cmtt-8"> +</span><span
|
|---|
| 3203 | class="cmtt-8"> [codebook</span><span
|
|---|
| 3204 | class="cmtt-8">_minimum</span><span
|
|---|
| 3205 | class="cmtt-8">_value]</span><span
|
|---|
| 3206 | class="cmtt-8"> +</span><span
|
|---|
| 3207 | class="cmtt-8"> [last];</span><br class="fancyvrb" /><a
|
|---|
| 3208 | id="x1-57016r8"></a><span
|
|---|
| 3209 | class="cmr-6">8</span>
|
|---|
| 3210 | <br class="fancyvrb" /><a
|
|---|
| 3211 | id="x1-57018r9"></a><span
|
|---|
| 3212 | class="cmr-6">9</span><span
|
|---|
| 3213 | class="cmtt-8"> </span><span
|
|---|
| 3214 | class="cmtt-8"> </span><span
|
|---|
| 3215 | class="cmtt-8"> </span><span
|
|---|
| 3216 | class="cmtt-8"> </span><span
|
|---|
| 3217 | class="cmtt-8"> </span><span
|
|---|
| 3218 | class="cmtt-8"> </span><span
|
|---|
| 3219 | class="cmtt-8"> 5)</span><span
|
|---|
| 3220 | class="cmtt-8"> if</span><span
|
|---|
| 3221 | class="cmtt-8"> (</span><span
|
|---|
| 3222 | class="cmtt-8"> [codebook</span><span
|
|---|
| 3223 | class="cmtt-8">_sequence</span><span
|
|---|
| 3224 | class="cmtt-8">_p]</span><span
|
|---|
| 3225 | class="cmtt-8"> is</span><span
|
|---|
| 3226 | class="cmtt-8"> set</span><span
|
|---|
| 3227 | class="cmtt-8"> )</span><span
|
|---|
| 3228 | class="cmtt-8"> then</span><span
|
|---|
| 3229 | class="cmtt-8"> set</span><span
|
|---|
| 3230 | class="cmtt-8"> [last]</span><span
|
|---|
| 3231 | class="cmtt-8"> =</span><span
|
|---|
| 3232 | class="cmtt-8"> vector</span><span
|
|---|
| 3233 | class="cmtt-8"> [value</span><span
|
|---|
| 3234 | class="cmtt-8">_vector]</span><span
|
|---|
| 3235 | class="cmtt-8"> element</span><span
|
|---|
| 3236 | class="cmtt-8"> [i]</span><br class="fancyvrb" /><a
|
|---|
| 3237 | id="x1-57020r10"></a><span
|
|---|
| 3238 | class="cmr-6">10</span>
|
|---|
| 3239 | <br class="fancyvrb" /><a
|
|---|
| 3240 | id="x1-57022r11"></a><span
|
|---|
| 3241 | class="cmr-6">11</span><span
|
|---|
| 3242 | class="cmtt-8"> </span><span
|
|---|
| 3243 | class="cmtt-8"> </span><span
|
|---|
| 3244 | class="cmtt-8"> </span><span
|
|---|
| 3245 | class="cmtt-8"> </span><span
|
|---|
| 3246 | class="cmtt-8"> </span><span
|
|---|
| 3247 | class="cmtt-8"> </span><span
|
|---|
| 3248 | class="cmtt-8"> 6)</span><span
|
|---|
| 3249 | class="cmtt-8"> increment</span><span
|
|---|
| 3250 | class="cmtt-8"> [multiplicand</span><span
|
|---|
| 3251 | class="cmtt-8">_offset]</span><br class="fancyvrb" /><a
|
|---|
| 3252 | id="x1-57024r12"></a><span
|
|---|
| 3253 | class="cmr-6">12</span><br class="fancyvrb" /><a
|
|---|
| 3254 | id="x1-57026r13"></a><span
|
|---|
| 3255 | class="cmr-6">13</span><span
|
|---|
| 3256 | class="cmtt-8"> </span><span
|
|---|
| 3257 | class="cmtt-8"> </span><span
|
|---|
| 3258 | class="cmtt-8"> </span><span
|
|---|
| 3259 | class="cmtt-8"> </span><span
|
|---|
| 3260 | class="cmtt-8"> </span><span
|
|---|
| 3261 | class="cmsy-8">}</span><br class="fancyvrb" /><a
|
|---|
| 3262 | id="x1-57028r14"></a><span
|
|---|
| 3263 | class="cmr-6">14</span><br class="fancyvrb" /><a
|
|---|
| 3264 | id="x1-57030r15"></a><span
|
|---|
| 3265 | class="cmr-6">15</span><span
|
|---|
| 3266 | class="cmtt-8"> </span><span
|
|---|
| 3267 | class="cmtt-8"> 7)</span><span
|
|---|
| 3268 | class="cmtt-8"> vector</span><span
|
|---|
| 3269 | class="cmtt-8"> calculation</span><span
|
|---|
| 3270 | class="cmtt-8"> completed.</span></div>
|
|---|
| 3271 |
|
|---|
| 3272 |
|
|---|
| 3273 |
|
|---|
| 3274 | <!--l. 420--><p class="noindent" >
|
|---|
| 3275 | <h4 class="subsectionHead"><span class="titlemark">3.3. </span> <a
|
|---|
| 3276 | id="x1-580003.3"></a>Use of the codebook abstraction</h4>
|
|---|
| 3277 | <!--l. 422--><p class="noindent" >The decoder uses the codebook abstraction much as it does the bit-unpacking convention; a
|
|---|
| 3278 | specific codebook reads a codeword from the bitstream, decoding it into an entry number, and
|
|---|
| 3279 | then returns that entry number to the decoder (when used in a scalar entropy coding context), or
|
|---|
| 3280 | uses that entry number as an offset into the VQ lookup table, returning a vector of values (when
|
|---|
| 3281 | used in a context desiring a VQ value). Scalar or VQ context is always explicit; any
|
|---|
| 3282 | call to the codebook mechanism requests either a scalar entry number or a lookup
|
|---|
| 3283 | vector.
|
|---|
| 3284 | <!--l. 432--><p class="noindent" >Note that VQ lookup type zero indicates that there is no lookup table; requesting
|
|---|
| 3285 | decode using a codebook of lookup type 0 in any context expecting a vector return
|
|---|
| 3286 | value (even in a case where a vector of dimension one) is forbidden. If decoder setup
|
|---|
| 3287 | or decode requests such an action, that is an error condition rendering the packet
|
|---|
| 3288 | undecodable.
|
|---|
| 3289 | <!--l. 439--><p class="noindent" >Using a codebook to read from the packet bitstream consists first of reading and decoding the
|
|---|
| 3290 | next codeword in the bitstream. The decoder reads bits until the accumulated bits match a
|
|---|
| 3291 | codeword in the codebook. This process can be though of as logically walking the
|
|---|
| 3292 | Huffman decode tree by reading one bit at a time from the bitstream, and using the
|
|---|
| 3293 | bit as a decision boolean to take the 0 branch (left in the above examples) or the 1
|
|---|
| 3294 | branch (right in the above examples). Walking the tree finishes when the decode process
|
|---|
| 3295 | hits a leaf in the decision tree; the result is the entry number corresponding to that
|
|---|
| 3296 | leaf. Reading past the end of a packet propagates the ’end-of-stream’ condition to the
|
|---|
| 3297 | decoder.
|
|---|
| 3298 | <!--l. 451--><p class="noindent" >When used in a scalar context, the resulting codeword entry is the desired return
|
|---|
| 3299 | value.
|
|---|
| 3300 | <!--l. 454--><p class="noindent" >When used in a VQ context, the codeword entry number is used as an offset into the VQ lookup
|
|---|
| 3301 | table. The value returned to the decoder is the vector of scalars corresponding to this
|
|---|
| 3302 | offset.
|
|---|
| 3303 |
|
|---|
| 3304 |
|
|---|
| 3305 |
|
|---|
| 3306 |
|
|---|
| 3307 |
|
|---|
| 3308 |
|
|---|
| 3309 | <h3 class="sectionHead"><span class="titlemark">4. </span> <a
|
|---|
| 3310 | id="x1-590004"></a>Codec Setup and Packet Decode</h3>
|
|---|
| 3311 | <!--l. 6--><p class="noindent" >
|
|---|
| 3312 | <h4 class="subsectionHead"><span class="titlemark">4.1. </span> <a
|
|---|
| 3313 | id="x1-600004.1"></a>Overview</h4>
|
|---|
| 3314 | <!--l. 8--><p class="noindent" >This document serves as the top-level reference document for the bit-by-bit decode specification
|
|---|
| 3315 | of Vorbis I. This document assumes a high-level understanding of the Vorbis decode
|
|---|
| 3316 | process, which is provided in <a
|
|---|
| 3317 | href="#x1-20001">section 1</a>, “<a
|
|---|
| 3318 | href="#x1-20001">Introduction and Description<!--tex4ht:ref: vorbis:spec:intro --></a>”. <a
|
|---|
| 3319 | href="#x1-360002">section 2</a>,
|
|---|
| 3320 | “<a
|
|---|
| 3321 | href="#x1-360002">Bitpacking Convention<!--tex4ht:ref: vorbis:spec:bitpacking --></a>” covers reading and writing bit fields from and to bitstream
|
|---|
| 3322 | packets.
|
|---|
| 3323 | <!--l. 16--><p class="noindent" >
|
|---|
| 3324 | <h4 class="subsectionHead"><span class="titlemark">4.2. </span> <a
|
|---|
| 3325 | id="x1-610004.2"></a>Header decode and decode setup</h4>
|
|---|
| 3326 | <!--l. 18--><p class="noindent" >A Vorbis bitstream begins with three header packets. The header packets are, in order, the
|
|---|
| 3327 | identification header, the comments header, and the setup header. All are required for decode
|
|---|
| 3328 | compliance. An end-of-packet condition during decoding the first or third header packet renders
|
|---|
| 3329 | the stream undecodable. End-of-packet decoding the comment header is a non-fatal error
|
|---|
| 3330 | condition.
|
|---|
| 3331 | <!--l. 25--><p class="noindent" >
|
|---|
| 3332 | <h5 class="subsubsectionHead"><span class="titlemark">4.2.1. </span> <a
|
|---|
| 3333 | id="x1-620004.2.1"></a>Common header decode</h5>
|
|---|
| 3334 | <!--l. 27--><p class="noindent" >Each header packet begins with the same header fields.
|
|---|
| 3335 | <!--l. 30--><p class="noindent" >
|
|---|
| 3336 | <div class="fancyvrb" id="fancyvrb20"><a
|
|---|
| 3337 | id="x1-62002r1"></a><span
|
|---|
| 3338 | class="cmr-6">1</span><span
|
|---|
| 3339 | class="cmtt-8"> </span><span
|
|---|
| 3340 | class="cmtt-8"> 1)</span><span
|
|---|
| 3341 | class="cmtt-8"> [packet</span><span
|
|---|
| 3342 | class="cmtt-8">_type]</span><span
|
|---|
| 3343 | class="cmtt-8"> :</span><span
|
|---|
| 3344 | class="cmtt-8"> 8</span><span
|
|---|
| 3345 | class="cmtt-8"> bit</span><span
|
|---|
| 3346 | class="cmtt-8"> value</span><br class="fancyvrb" /><a
|
|---|
| 3347 | id="x1-62004r2"></a><span
|
|---|
| 3348 | class="cmr-6">2</span><span
|
|---|
| 3349 | class="cmtt-8"> </span><span
|
|---|
| 3350 | class="cmtt-8"> 2)</span><span
|
|---|
| 3351 | class="cmtt-8"> 0x76,</span><span
|
|---|
| 3352 | class="cmtt-8"> 0x6f,</span><span
|
|---|
| 3353 | class="cmtt-8"> 0x72,</span><span
|
|---|
| 3354 | class="cmtt-8"> 0x62,</span><span
|
|---|
| 3355 | class="cmtt-8"> 0x69,</span><span
|
|---|
| 3356 | class="cmtt-8"> 0x73:</span><span
|
|---|
| 3357 | class="cmtt-8"> the</span><span
|
|---|
| 3358 | class="cmtt-8"> characters</span><span
|
|---|
| 3359 | class="cmtt-8"> ’v’,’o’,’r’,’b’,’i’,’s’</span><span
|
|---|
| 3360 | class="cmtt-8"> as</span><span
|
|---|
| 3361 | class="cmtt-8"> six</span><span
|
|---|
| 3362 | class="cmtt-8"> octets</span></div>
|
|---|
| 3363 | <!--l. 35--><p class="noindent" >Decode continues according to packet type; the identification header is type 1, the comment
|
|---|
| 3364 | header type 3 and the setup header type 5 (these types are all odd as a packet with a leading
|
|---|
| 3365 | single bit of ’0’ is an audio packet). The packets must occur in the order of identification,
|
|---|
| 3366 |
|
|---|
| 3367 |
|
|---|
| 3368 |
|
|---|
| 3369 | comment, setup.
|
|---|
| 3370 | <!--l. 43--><p class="noindent" >
|
|---|
| 3371 | <h5 class="subsubsectionHead"><span class="titlemark">4.2.2. </span> <a
|
|---|
| 3372 | id="x1-630004.2.2"></a>Identification header</h5>
|
|---|
| 3373 | <!--l. 45--><p class="noindent" >The identification header is a short header of only a few fields used to declare the stream
|
|---|
| 3374 | definitively as Vorbis, and provide a few externally relevant pieces of information about the audio
|
|---|
| 3375 | stream. The identification header is coded as follows:
|
|---|
| 3376 | <!--l. 50--><p class="noindent" >
|
|---|
| 3377 | <div class="fancyvrb" id="fancyvrb21"><a
|
|---|
| 3378 | id="x1-63002r1"></a><span
|
|---|
| 3379 | class="cmr-6">1</span><span
|
|---|
| 3380 | class="cmtt-8"> 1)</span><span
|
|---|
| 3381 | class="cmtt-8"> [vorbis</span><span
|
|---|
| 3382 | class="cmtt-8">_version]</span><span
|
|---|
| 3383 | class="cmtt-8"> =</span><span
|
|---|
| 3384 | class="cmtt-8"> read</span><span
|
|---|
| 3385 | class="cmtt-8"> 32</span><span
|
|---|
| 3386 | class="cmtt-8"> bits</span><span
|
|---|
| 3387 | class="cmtt-8"> as</span><span
|
|---|
| 3388 | class="cmtt-8"> unsigned</span><span
|
|---|
| 3389 | class="cmtt-8"> integer</span><br class="fancyvrb" /><a
|
|---|
| 3390 | id="x1-63004r2"></a><span
|
|---|
| 3391 | class="cmr-6">2</span><span
|
|---|
| 3392 | class="cmtt-8"> 2)</span><span
|
|---|
| 3393 | class="cmtt-8"> [audio</span><span
|
|---|
| 3394 | class="cmtt-8">_channels]</span><span
|
|---|
| 3395 | class="cmtt-8"> =</span><span
|
|---|
| 3396 | class="cmtt-8"> read</span><span
|
|---|
| 3397 | class="cmtt-8"> 8</span><span
|
|---|
| 3398 | class="cmtt-8"> bit</span><span
|
|---|
| 3399 | class="cmtt-8"> integer</span><span
|
|---|
| 3400 | class="cmtt-8"> as</span><span
|
|---|
| 3401 | class="cmtt-8"> unsigned</span>
|
|---|
| 3402 | <br class="fancyvrb" /><a
|
|---|
| 3403 | id="x1-63006r3"></a><span
|
|---|
| 3404 | class="cmr-6">3</span><span
|
|---|
| 3405 | class="cmtt-8"> 3)</span><span
|
|---|
| 3406 | class="cmtt-8"> [audio</span><span
|
|---|
| 3407 | class="cmtt-8">_sample</span><span
|
|---|
| 3408 | class="cmtt-8">_rate]</span><span
|
|---|
| 3409 | class="cmtt-8"> =</span><span
|
|---|
| 3410 | class="cmtt-8"> read</span><span
|
|---|
| 3411 | class="cmtt-8"> 32</span><span
|
|---|
| 3412 | class="cmtt-8"> bits</span><span
|
|---|
| 3413 | class="cmtt-8"> as</span><span
|
|---|
| 3414 | class="cmtt-8"> unsigned</span><span
|
|---|
| 3415 | class="cmtt-8"> integer</span><br class="fancyvrb" /><a
|
|---|
| 3416 | id="x1-63008r4"></a><span
|
|---|
| 3417 | class="cmr-6">4</span><span
|
|---|
| 3418 | class="cmtt-8"> 4)</span><span
|
|---|
| 3419 | class="cmtt-8"> [bitrate</span><span
|
|---|
| 3420 | class="cmtt-8">_maximum]</span><span
|
|---|
| 3421 | class="cmtt-8"> =</span><span
|
|---|
| 3422 | class="cmtt-8"> read</span><span
|
|---|
| 3423 | class="cmtt-8"> 32</span><span
|
|---|
| 3424 | class="cmtt-8"> bits</span><span
|
|---|
| 3425 | class="cmtt-8"> as</span><span
|
|---|
| 3426 | class="cmtt-8"> signed</span><span
|
|---|
| 3427 | class="cmtt-8"> integer</span>
|
|---|
| 3428 | <br class="fancyvrb" /><a
|
|---|
| 3429 | id="x1-63010r5"></a><span
|
|---|
| 3430 | class="cmr-6">5</span><span
|
|---|
| 3431 | class="cmtt-8"> 5)</span><span
|
|---|
| 3432 | class="cmtt-8"> [bitrate</span><span
|
|---|
| 3433 | class="cmtt-8">_nominal]</span><span
|
|---|
| 3434 | class="cmtt-8"> =</span><span
|
|---|
| 3435 | class="cmtt-8"> read</span><span
|
|---|
| 3436 | class="cmtt-8"> 32</span><span
|
|---|
| 3437 | class="cmtt-8"> bits</span><span
|
|---|
| 3438 | class="cmtt-8"> as</span><span
|
|---|
| 3439 | class="cmtt-8"> signed</span><span
|
|---|
| 3440 | class="cmtt-8"> integer</span><br class="fancyvrb" /><a
|
|---|
| 3441 | id="x1-63012r6"></a><span
|
|---|
| 3442 | class="cmr-6">6</span><span
|
|---|
| 3443 | class="cmtt-8"> 6)</span><span
|
|---|
| 3444 | class="cmtt-8"> [bitrate</span><span
|
|---|
| 3445 | class="cmtt-8">_minimum]</span><span
|
|---|
| 3446 | class="cmtt-8"> =</span><span
|
|---|
| 3447 | class="cmtt-8"> read</span><span
|
|---|
| 3448 | class="cmtt-8"> 32</span><span
|
|---|
| 3449 | class="cmtt-8"> bits</span><span
|
|---|
| 3450 | class="cmtt-8"> as</span><span
|
|---|
| 3451 | class="cmtt-8"> signed</span><span
|
|---|
| 3452 | class="cmtt-8"> integer</span>
|
|---|
| 3453 | <br class="fancyvrb" /><a
|
|---|
| 3454 | id="x1-63014r7"></a><span
|
|---|
| 3455 | class="cmr-6">7</span><span
|
|---|
| 3456 | class="cmtt-8"> 7)</span><span
|
|---|
| 3457 | class="cmtt-8"> [blocksize</span><span
|
|---|
| 3458 | class="cmtt-8">_0]</span><span
|
|---|
| 3459 | class="cmtt-8"> =</span><span
|
|---|
| 3460 | class="cmtt-8"> 2</span><span
|
|---|
| 3461 | class="cmtt-8"> exponent</span><span
|
|---|
| 3462 | class="cmtt-8"> (read</span><span
|
|---|
| 3463 | class="cmtt-8"> 4</span><span
|
|---|
| 3464 | class="cmtt-8"> bits</span><span
|
|---|
| 3465 | class="cmtt-8"> as</span><span
|
|---|
| 3466 | class="cmtt-8"> unsigned</span><span
|
|---|
| 3467 | class="cmtt-8"> integer)</span><br class="fancyvrb" /><a
|
|---|
| 3468 | id="x1-63016r8"></a><span
|
|---|
| 3469 | class="cmr-6">8</span><span
|
|---|
| 3470 | class="cmtt-8"> 8)</span><span
|
|---|
| 3471 | class="cmtt-8"> [blocksize</span><span
|
|---|
| 3472 | class="cmtt-8">_1]</span><span
|
|---|
| 3473 | class="cmtt-8"> =</span><span
|
|---|
| 3474 | class="cmtt-8"> 2</span><span
|
|---|
| 3475 | class="cmtt-8"> exponent</span><span
|
|---|
| 3476 | class="cmtt-8"> (read</span><span
|
|---|
| 3477 | class="cmtt-8"> 4</span><span
|
|---|
| 3478 | class="cmtt-8"> bits</span><span
|
|---|
| 3479 | class="cmtt-8"> as</span><span
|
|---|
| 3480 | class="cmtt-8"> unsigned</span><span
|
|---|
| 3481 | class="cmtt-8"> integer)</span>
|
|---|
| 3482 | <br class="fancyvrb" /><a
|
|---|
| 3483 | id="x1-63018r9"></a><span
|
|---|
| 3484 | class="cmr-6">9</span><span
|
|---|
| 3485 | class="cmtt-8"> 9)</span><span
|
|---|
| 3486 | class="cmtt-8"> [framing</span><span
|
|---|
| 3487 | class="cmtt-8">_flag]</span><span
|
|---|
| 3488 | class="cmtt-8"> =</span><span
|
|---|
| 3489 | class="cmtt-8"> read</span><span
|
|---|
| 3490 | class="cmtt-8"> one</span><span
|
|---|
| 3491 | class="cmtt-8"> bit</span></div>
|
|---|
| 3492 | <!--l. 62--><p class="noindent" ><span
|
|---|
| 3493 | class="cmtt-12">[vorbis</span><span
|
|---|
| 3494 | class="cmtt-12">_version] </span>is to read ’0’ in order to be compatible with this document. Both
|
|---|
| 3495 | <span
|
|---|
| 3496 | class="cmtt-12">[audio</span><span
|
|---|
| 3497 | class="cmtt-12">_channels] </span>and <span
|
|---|
| 3498 | class="cmtt-12">[audio</span><span
|
|---|
| 3499 | class="cmtt-12">_sample</span><span
|
|---|
| 3500 | class="cmtt-12">_rate] </span>must read greater than zero. Allowed final
|
|---|
| 3501 | blocksize values are 64, 128, 256, 512, 1024, 2048, 4096 and 8192 in Vorbis I. <span
|
|---|
| 3502 | class="cmtt-12">[blocksize</span><span
|
|---|
| 3503 | class="cmtt-12">_0]</span>
|
|---|
| 3504 | must be less than or equal to <span
|
|---|
| 3505 | class="cmtt-12">[blocksize</span><span
|
|---|
| 3506 | class="cmtt-12">_1]</span>. The framing bit must be nonzero. Failure to meet
|
|---|
| 3507 | any of these conditions renders a stream undecodable.
|
|---|
| 3508 | <!--l. 70--><p class="noindent" >The bitrate fields above are used only as hints. The nominal bitrate field especially may be
|
|---|
| 3509 | considerably off in purely VBR streams. The fields are meaningful only when greater than
|
|---|
| 3510 | zero.
|
|---|
| 3511 | <ul class="itemize1">
|
|---|
| 3512 | <li class="itemize">All three fields set to the same value implies a fixed rate, or tightly bounded, nearly
|
|---|
| 3513 | fixed-rate bitstream
|
|---|
| 3514 | </li>
|
|---|
| 3515 | <li class="itemize">Only nominal set implies a VBR or ABR stream that averages the nominal bitrate
|
|---|
| 3516 | </li>
|
|---|
| 3517 | <li class="itemize">Maximum and or minimum set implies a VBR bitstream that obeys the bitrate limits
|
|---|
| 3518 | </li>
|
|---|
| 3519 | <li class="itemize">None set indicates the encoder does not care to speculate.</li></ul>
|
|---|
| 3520 |
|
|---|
| 3521 |
|
|---|
| 3522 |
|
|---|
| 3523 | <!--l. 84--><p class="noindent" >
|
|---|
| 3524 | <h5 class="subsubsectionHead"><span class="titlemark">4.2.3. </span> <a
|
|---|
| 3525 | id="x1-640004.2.3"></a>Comment header</h5>
|
|---|
| 3526 | <!--l. 85--><p class="noindent" >Comment header decode and data specification is covered in <a
|
|---|
| 3527 | href="#x1-820005">section 5</a>, “<a
|
|---|
| 3528 | href="#x1-820005">comment field and
|
|---|
| 3529 | header specification<!--tex4ht:ref: vorbis:spec:comment --></a>”.
|
|---|
| 3530 | <!--l. 89--><p class="noindent" >
|
|---|
| 3531 | <h5 class="subsubsectionHead"><span class="titlemark">4.2.4. </span> <a
|
|---|
| 3532 | id="x1-650004.2.4"></a>Setup header</h5>
|
|---|
| 3533 | <!--l. 91--><p class="noindent" >Vorbis codec setup is configurable to an extreme degree:
|
|---|
| 3534 | <div class="center"
|
|---|
| 3535 | >
|
|---|
| 3536 | <!--l. 93--><p class="noindent" >
|
|---|
| 3537 |
|
|---|
| 3538 | <!--l. 94--><p class="noindent" ><img
|
|---|
| 3539 | src="components.png" alt="PIC"
|
|---|
| 3540 | >
|
|---|
| 3541 | <br /> <div class="caption"
|
|---|
| 3542 | ><span class="id">Figure 6: </span><span
|
|---|
| 3543 | class="content">decoder pipeline configuration</span></div><!--tex4ht:label?: x1-650016 -->
|
|---|
| 3544 | </div>
|
|---|
| 3545 | <!--l. 99--><p class="noindent" >The setup header contains the bulk of the codec setup information needed for decode. The setup
|
|---|
| 3546 | header contains, in order, the lists of codebook configurations, time-domain transform
|
|---|
| 3547 | configurations (placeholders in Vorbis I), floor configurations, residue configurations, channel
|
|---|
| 3548 | mapping configurations and mode configurations. It finishes with a framing bit of ’1’. Header
|
|---|
| 3549 | decode proceeds in the following order:
|
|---|
| 3550 | <!--l. 107--><p class="noindent" ><span class="paragraphHead"><a
|
|---|
| 3551 | id="x1-660004.2.4"></a><span
|
|---|
| 3552 | class="cmbx-12">Codebooks</span></span>
|
|---|
| 3553 | <dl class="enumerate-enumitem"><dt class="enumerate-enumitem">
|
|---|
| 3554 | 1. </dt><dd
|
|---|
| 3555 | class="enumerate-enumitem"><span
|
|---|
| 3556 | class="cmtt-12">[vorbis</span><span
|
|---|
| 3557 | class="cmtt-12">_codebook</span><span
|
|---|
| 3558 | class="cmtt-12">_count] </span>= read eight bits as unsigned integer and add one
|
|---|
| 3559 | </dd><dt class="enumerate-enumitem">
|
|---|
| 3560 | 2. </dt><dd
|
|---|
| 3561 | class="enumerate-enumitem">Decode <span
|
|---|
| 3562 | class="cmtt-12">[vorbis</span><span
|
|---|
| 3563 | class="cmtt-12">_codebook</span><span
|
|---|
| 3564 | class="cmtt-12">_count] </span>codebooks in order as defined in <a
|
|---|
| 3565 | href="#x1-470003">section 3</a>,
|
|---|
| 3566 | “<a
|
|---|
| 3567 | href="#x1-470003">Probability Model and Codebooks<!--tex4ht:ref: vorbis:spec:codebook --></a>”. Save each configuration, in order, in an array
|
|---|
| 3568 | of codebook configurations <span
|
|---|
| 3569 | class="cmtt-12">[vorbis</span><span
|
|---|
| 3570 | class="cmtt-12">_codebook</span><span
|
|---|
| 3571 | class="cmtt-12">_configurations]</span>.</dd></dl>
|
|---|
| 3572 |
|
|---|
| 3573 |
|
|---|
| 3574 |
|
|---|
| 3575 | <!--l. 119--><p class="noindent" ><span class="paragraphHead"><a
|
|---|
| 3576 | id="x1-670004.2.4"></a><span
|
|---|
| 3577 | class="cmbx-12">Time domain transforms</span></span>
|
|---|
| 3578 | These hooks are placeholders in Vorbis I. Nevertheless, the configuration placeholder values must
|
|---|
| 3579 | be read to maintain bitstream sync.
|
|---|
| 3580 | <!--l. 126--><p class="noindent" >
|
|---|
| 3581 | <dl class="enumerate-enumitem"><dt class="enumerate-enumitem">
|
|---|
| 3582 | 1. </dt><dd
|
|---|
| 3583 | class="enumerate-enumitem"><span
|
|---|
| 3584 | class="cmtt-12">[vorbis</span><span
|
|---|
| 3585 | class="cmtt-12">_time</span><span
|
|---|
| 3586 | class="cmtt-12">_count] </span>= read 6 bits as unsigned integer and add one
|
|---|
| 3587 | </dd><dt class="enumerate-enumitem">
|
|---|
| 3588 | 2. </dt><dd
|
|---|
| 3589 | class="enumerate-enumitem">read <span
|
|---|
| 3590 | class="cmtt-12">[vorbis</span><span
|
|---|
| 3591 | class="cmtt-12">_time</span><span
|
|---|
| 3592 | class="cmtt-12">_count] </span>16 bit values; each value should be zero. If any value is
|
|---|
| 3593 | nonzero, this is an error condition and the stream is undecodable.</dd></dl>
|
|---|
| 3594 | <!--l. 132--><p class="noindent" ><span class="paragraphHead"><a
|
|---|
| 3595 | id="x1-680004.2.4"></a><span
|
|---|
| 3596 | class="cmbx-12">Floors</span></span>
|
|---|
| 3597 | Vorbis uses two floor types; header decode is handed to the decode abstraction of the appropriate
|
|---|
| 3598 | type.
|
|---|
| 3599 | <!--l. 138--><p class="noindent" >
|
|---|
| 3600 | <dl class="enumerate-enumitem"><dt class="enumerate-enumitem">
|
|---|
| 3601 | 1. </dt><dd
|
|---|
| 3602 | class="enumerate-enumitem"><span
|
|---|
| 3603 | class="cmtt-12">[vorbis</span><span
|
|---|
| 3604 | class="cmtt-12">_floor</span><span
|
|---|
| 3605 | class="cmtt-12">_count] </span>= read 6 bits as unsigned integer and add one
|
|---|
| 3606 | </dd><dt class="enumerate-enumitem">
|
|---|
| 3607 | 2. </dt><dd
|
|---|
| 3608 | class="enumerate-enumitem">For each <span
|
|---|
| 3609 | class="cmtt-12">[i] </span>of <span
|
|---|
| 3610 | class="cmtt-12">[vorbis</span><span
|
|---|
| 3611 | class="cmtt-12">_floor</span><span
|
|---|
| 3612 | class="cmtt-12">_count] </span>floor numbers:
|
|---|
| 3613 | <dl class="enumerate-enumitem"><dt class="enumerate-enumitem">
|
|---|
| 3614 | a) </dt><dd
|
|---|
| 3615 | class="enumerate-enumitem">read the floor type: vector <span
|
|---|
| 3616 | class="cmtt-12">[vorbis</span><span
|
|---|
| 3617 | class="cmtt-12">_floor</span><span
|
|---|
| 3618 | class="cmtt-12">_types] </span>element <span
|
|---|
| 3619 | class="cmtt-12">[i] </span>= read 16 bits
|
|---|
| 3620 | as unsigned integer
|
|---|
| 3621 | </dd><dt class="enumerate-enumitem">
|
|---|
| 3622 | b) </dt><dd
|
|---|
| 3623 | class="enumerate-enumitem">If the floor type is zero, decode the floor configuration as defined in <a
|
|---|
| 3624 | href="#x1-900006">section 6</a>,
|
|---|
| 3625 | “<a
|
|---|
| 3626 | href="#x1-900006">Floor type 0 setup and decode<!--tex4ht:ref: vorbis:spec:floor0 --></a>”; save this configuration in slot <span
|
|---|
| 3627 | class="cmtt-12">[i] </span>of the floor
|
|---|
| 3628 | configuration array <span
|
|---|
| 3629 | class="cmtt-12">[vorbis</span><span
|
|---|
| 3630 | class="cmtt-12">_floor</span><span
|
|---|
| 3631 | class="cmtt-12">_configurations]</span>.
|
|---|
| 3632 | </dd><dt class="enumerate-enumitem">
|
|---|
| 3633 | c) </dt><dd
|
|---|
| 3634 | class="enumerate-enumitem">If the floor type is one, decode the floor configuration as defined in <a
|
|---|
| 3635 | href="#x1-970007">section 7</a>,
|
|---|
| 3636 | “<a
|
|---|
| 3637 | href="#x1-970007">Floor type 1 setup and decode<!--tex4ht:ref: vorbis:spec:floor1 --></a>”; save this configuration in slot <span
|
|---|
| 3638 | class="cmtt-12">[i] </span>of the floor
|
|---|
| 3639 | configuration array <span
|
|---|
| 3640 | class="cmtt-12">[vorbis</span><span
|
|---|
| 3641 | class="cmtt-12">_floor</span><span
|
|---|
| 3642 | class="cmtt-12">_configurations]</span>.
|
|---|
| 3643 | </dd><dt class="enumerate-enumitem">
|
|---|
| 3644 | d) </dt><dd
|
|---|
| 3645 | class="enumerate-enumitem">If the the floor type is greater than one, this stream is undecodable; ERROR
|
|---|
| 3646 | CONDITION</dd></dl>
|
|---|
| 3647 |
|
|---|
| 3648 |
|
|---|
| 3649 |
|
|---|
| 3650 | </dd></dl>
|
|---|
| 3651 | <!--l. 156--><p class="noindent" ><span class="paragraphHead"><a
|
|---|
| 3652 | id="x1-690004.2.4"></a><span
|
|---|
| 3653 | class="cmbx-12">Residues</span></span>
|
|---|
| 3654 | Vorbis uses three residue types; header decode of each type is identical.
|
|---|
| 3655 | <!--l. 162--><p class="noindent" >
|
|---|
| 3656 | <dl class="enumerate-enumitem"><dt class="enumerate-enumitem">
|
|---|
| 3657 | 1. </dt><dd
|
|---|
| 3658 | class="enumerate-enumitem"><span
|
|---|
| 3659 | class="cmtt-12">[vorbis</span><span
|
|---|
| 3660 | class="cmtt-12">_residue</span><span
|
|---|
| 3661 | class="cmtt-12">_count] </span>= read 6 bits as unsigned integer and add one
|
|---|
| 3662 | </dd><dt class="enumerate-enumitem">
|
|---|
| 3663 | 2. </dt><dd
|
|---|
| 3664 | class="enumerate-enumitem">For each of <span
|
|---|
| 3665 | class="cmtt-12">[vorbis</span><span
|
|---|
| 3666 | class="cmtt-12">_residue</span><span
|
|---|
| 3667 | class="cmtt-12">_count] </span>residue numbers:
|
|---|
| 3668 | <dl class="enumerate-enumitem"><dt class="enumerate-enumitem">
|
|---|
| 3669 | a) </dt><dd
|
|---|
| 3670 | class="enumerate-enumitem">read the residue type; vector <span
|
|---|
| 3671 | class="cmtt-12">[vorbis</span><span
|
|---|
| 3672 | class="cmtt-12">_residue</span><span
|
|---|
| 3673 | class="cmtt-12">_types] </span>element <span
|
|---|
| 3674 | class="cmtt-12">[i] </span>= read 16
|
|---|
| 3675 | bits as unsigned integer
|
|---|
| 3676 | </dd><dt class="enumerate-enumitem">
|
|---|
| 3677 | b) </dt><dd
|
|---|
| 3678 | class="enumerate-enumitem">If the residue type is zero, one or two, decode the residue configuration as defined
|
|---|
| 3679 | in <a
|
|---|
| 3680 | href="#x1-1040008">section 8</a>, “<a
|
|---|
| 3681 | href="#x1-1040008">Residue setup and decode<!--tex4ht:ref: vorbis:spec:residue --></a>”; save this configuration in slot <span
|
|---|
| 3682 | class="cmtt-12">[i] </span>of
|
|---|
| 3683 | the residue configuration array <span
|
|---|
| 3684 | class="cmtt-12">[vorbis</span><span
|
|---|
| 3685 | class="cmtt-12">_residue</span><span
|
|---|
| 3686 | class="cmtt-12">_configurations]</span>.
|
|---|
| 3687 | </dd><dt class="enumerate-enumitem">
|
|---|
| 3688 | c) </dt><dd
|
|---|
| 3689 | class="enumerate-enumitem">If the the residue type is greater than two, this stream is undecodable; ERROR
|
|---|
| 3690 | CONDITION</dd></dl>
|
|---|
| 3691 | </dd></dl>
|
|---|
| 3692 | <!--l. 176--><p class="noindent" ><span class="paragraphHead"><a
|
|---|
| 3693 | id="x1-700004.2.4"></a><span
|
|---|
| 3694 | class="cmbx-12">Mappings</span></span>
|
|---|
| 3695 | Mappings are used to set up specific pipelines for encoding multichannel audio with varying
|
|---|
| 3696 | channel mapping applications. Vorbis I uses a single mapping type (0), with implicit PCM
|
|---|
| 3697 | channel mappings.
|
|---|
| 3698 | <!--l. 187--><p class="noindent" >
|
|---|
| 3699 | <dl class="enumerate-enumitem"><dt class="enumerate-enumitem">
|
|---|
| 3700 | 1. </dt><dd
|
|---|
| 3701 | class="enumerate-enumitem"><span
|
|---|
| 3702 | class="cmtt-12">[vorbis</span><span
|
|---|
| 3703 | class="cmtt-12">_mapping</span><span
|
|---|
| 3704 | class="cmtt-12">_count] </span>= read 6 bits as unsigned integer and add one
|
|---|
| 3705 | </dd><dt class="enumerate-enumitem">
|
|---|
| 3706 | 2. </dt><dd
|
|---|
| 3707 | class="enumerate-enumitem">For each <span
|
|---|
| 3708 | class="cmtt-12">[i] </span>of <span
|
|---|
| 3709 | class="cmtt-12">[vorbis</span><span
|
|---|
| 3710 | class="cmtt-12">_mapping</span><span
|
|---|
| 3711 | class="cmtt-12">_count] </span>mapping numbers:
|
|---|
| 3712 |
|
|---|
| 3713 |
|
|---|
| 3714 |
|
|---|
| 3715 | <dl class="enumerate-enumitem"><dt class="enumerate-enumitem">
|
|---|
| 3716 | a) </dt><dd
|
|---|
| 3717 | class="enumerate-enumitem">read the mapping type: 16 bits as unsigned integer. There’s no reason to save
|
|---|
| 3718 | the mapping type in Vorbis I.
|
|---|
| 3719 | </dd><dt class="enumerate-enumitem">
|
|---|
| 3720 | b) </dt><dd
|
|---|
| 3721 | class="enumerate-enumitem">If the mapping type is nonzero, the stream is undecodable
|
|---|
| 3722 | </dd><dt class="enumerate-enumitem">
|
|---|
| 3723 | c) </dt><dd
|
|---|
| 3724 | class="enumerate-enumitem">If the mapping type is zero:
|
|---|
| 3725 | <dl class="enumerate-enumitem"><dt class="enumerate-enumitem">
|
|---|
| 3726 | i. </dt><dd
|
|---|
| 3727 | class="enumerate-enumitem">read 1 bit as a boolean flag
|
|---|
| 3728 | <dl class="enumerate-enumitem"><dt class="enumerate-enumitem">
|
|---|
| 3729 | A. </dt><dd
|
|---|
| 3730 | class="enumerate-enumitem">if set, <span
|
|---|
| 3731 | class="cmtt-12">[vorbis</span><span
|
|---|
| 3732 | class="cmtt-12">_mapping</span><span
|
|---|
| 3733 | class="cmtt-12">_submaps] </span>= read 4 bits as unsigned integer
|
|---|
| 3734 | and add one
|
|---|
| 3735 | </dd><dt class="enumerate-enumitem">
|
|---|
| 3736 | B. </dt><dd
|
|---|
| 3737 | class="enumerate-enumitem">if unset, <span
|
|---|
| 3738 | class="cmtt-12">[vorbis</span><span
|
|---|
| 3739 | class="cmtt-12">_mapping</span><span
|
|---|
| 3740 | class="cmtt-12">_submaps] </span>= 1</dd></dl>
|
|---|
| 3741 | </dd><dt class="enumerate-enumitem">
|
|---|
| 3742 | ii. </dt><dd
|
|---|
| 3743 | class="enumerate-enumitem">read 1 bit as a boolean flag
|
|---|
| 3744 | <dl class="enumerate-enumitem"><dt class="enumerate-enumitem">
|
|---|
| 3745 | A. </dt><dd
|
|---|
| 3746 | class="enumerate-enumitem">if set, square polar channel mapping is in use:
|
|---|
| 3747 | <ul class="itemize1">
|
|---|
| 3748 | <li class="itemize"><span
|
|---|
| 3749 | class="cmtt-12">[vorbis</span><span
|
|---|
| 3750 | class="cmtt-12">_mapping</span><span
|
|---|
| 3751 | class="cmtt-12">_coupling</span><span
|
|---|
| 3752 | class="cmtt-12">_steps] </span>= read 8 bits as unsigned
|
|---|
| 3753 | integer and add one
|
|---|
| 3754 | </li>
|
|---|
| 3755 | <li class="itemize">for <span
|
|---|
| 3756 | class="cmtt-12">[j] </span>each of <span
|
|---|
| 3757 | class="cmtt-12">[vorbis</span><span
|
|---|
| 3758 | class="cmtt-12">_mapping</span><span
|
|---|
| 3759 | class="cmtt-12">_coupling</span><span
|
|---|
| 3760 | class="cmtt-12">_steps] </span>steps:
|
|---|
| 3761 | <ul class="itemize2">
|
|---|
| 3762 | <li class="itemize">vector <span
|
|---|
| 3763 | class="cmtt-12">[vorbis</span><span
|
|---|
| 3764 | class="cmtt-12">_mapping</span><span
|
|---|
| 3765 | class="cmtt-12">_magnitude] </span>element <span
|
|---|
| 3766 | class="cmtt-12">[j]</span>= read
|
|---|
| 3767 | <a
|
|---|
| 3768 | href="#x1-1190009.2.1">ilog</a>(<span
|
|---|
| 3769 | class="cmtt-12">[audio</span><span
|
|---|
| 3770 | class="cmtt-12">_channels] </span>- 1) bits as unsigned integer
|
|---|
| 3771 | </li>
|
|---|
| 3772 | <li class="itemize">vector <span
|
|---|
| 3773 | class="cmtt-12">[vorbis</span><span
|
|---|
| 3774 | class="cmtt-12">_mapping</span><span
|
|---|
| 3775 | class="cmtt-12">_angle] </span>element <span
|
|---|
| 3776 | class="cmtt-12">[j]</span>= read
|
|---|
| 3777 | <a
|
|---|
| 3778 | href="#x1-1190009.2.1">ilog</a>(<span
|
|---|
| 3779 | class="cmtt-12">[audio</span><span
|
|---|
| 3780 | class="cmtt-12">_channels] </span>- 1) bits as unsigned integer
|
|---|
| 3781 | </li>
|
|---|
| 3782 | <li class="itemize">the numbers read in the above two steps are channel numbers
|
|---|
| 3783 | representing the channel to treat as magnitude and the channel
|
|---|
| 3784 | to treat as angle, respectively. If for any coupling step the
|
|---|
| 3785 | angle channel number equals the magnitude channel number, the
|
|---|
| 3786 | magnitude channel number is greater than <span
|
|---|
| 3787 | class="cmtt-12">[audio</span><span
|
|---|
| 3788 | class="cmtt-12">_channels]</span>-1, or
|
|---|
| 3789 | the angle channel is greater than <span
|
|---|
| 3790 | class="cmtt-12">[audio</span><span
|
|---|
| 3791 | class="cmtt-12">_channels]</span>-1, the stream
|
|---|
| 3792 | is undecodable.</li></ul>
|
|---|
| 3793 |
|
|---|
| 3794 |
|
|---|
| 3795 |
|
|---|
| 3796 | </li></ul>
|
|---|
| 3797 | </dd><dt class="enumerate-enumitem">
|
|---|
| 3798 | B. </dt><dd
|
|---|
| 3799 | class="enumerate-enumitem">if unset, <span
|
|---|
| 3800 | class="cmtt-12">[vorbis</span><span
|
|---|
| 3801 | class="cmtt-12">_mapping</span><span
|
|---|
| 3802 | class="cmtt-12">_coupling</span><span
|
|---|
| 3803 | class="cmtt-12">_steps] </span>= 0</dd></dl>
|
|---|
| 3804 | </dd><dt class="enumerate-enumitem">
|
|---|
| 3805 | iii. </dt><dd
|
|---|
| 3806 | class="enumerate-enumitem">read 2 bits (reserved field); if the value is nonzero, the stream is undecodable
|
|---|
| 3807 | </dd><dt class="enumerate-enumitem">
|
|---|
| 3808 | iv. </dt><dd
|
|---|
| 3809 | class="enumerate-enumitem">if <span
|
|---|
| 3810 | class="cmtt-12">[vorbis</span><span
|
|---|
| 3811 | class="cmtt-12">_mapping</span><span
|
|---|
| 3812 | class="cmtt-12">_submaps] </span>is greater than one, we read channel multiplex
|
|---|
| 3813 | settings. For each <span
|
|---|
| 3814 | class="cmtt-12">[j] </span>of <span
|
|---|
| 3815 | class="cmtt-12">[audio</span><span
|
|---|
| 3816 | class="cmtt-12">_channels] </span>channels:
|
|---|
| 3817 | <dl class="enumerate-enumitem"><dt class="enumerate-enumitem">
|
|---|
| 3818 | A. </dt><dd
|
|---|
| 3819 | class="enumerate-enumitem">vector <span
|
|---|
| 3820 | class="cmtt-12">[vorbis</span><span
|
|---|
| 3821 | class="cmtt-12">_mapping</span><span
|
|---|
| 3822 | class="cmtt-12">_mux] </span>element <span
|
|---|
| 3823 | class="cmtt-12">[j] </span>= read 4 bits as unsigned
|
|---|
| 3824 | integer
|
|---|
| 3825 | </dd><dt class="enumerate-enumitem">
|
|---|
| 3826 | B. </dt><dd
|
|---|
| 3827 | class="enumerate-enumitem">if the value is greater than the highest numbered submap
|
|---|
| 3828 | (<span
|
|---|
| 3829 | class="cmtt-12">[vorbis</span><span
|
|---|
| 3830 | class="cmtt-12">_mapping</span><span
|
|---|
| 3831 | class="cmtt-12">_submaps] </span>- 1), this in an error condition rendering
|
|---|
| 3832 | the stream undecodable</dd></dl>
|
|---|
| 3833 | </dd><dt class="enumerate-enumitem">
|
|---|
| 3834 | v. </dt><dd
|
|---|
| 3835 | class="enumerate-enumitem">for each submap <span
|
|---|
| 3836 | class="cmtt-12">[j] </span>of <span
|
|---|
| 3837 | class="cmtt-12">[vorbis</span><span
|
|---|
| 3838 | class="cmtt-12">_mapping</span><span
|
|---|
| 3839 | class="cmtt-12">_submaps] </span>submaps, read the floor and
|
|---|
| 3840 | residue numbers for use in decoding that submap:
|
|---|
| 3841 | <dl class="enumerate-enumitem"><dt class="enumerate-enumitem">
|
|---|
| 3842 | A. </dt><dd
|
|---|
| 3843 | class="enumerate-enumitem">read and discard 8 bits (the unused time configuration placeholder)
|
|---|
| 3844 | </dd><dt class="enumerate-enumitem">
|
|---|
| 3845 | B. </dt><dd
|
|---|
| 3846 | class="enumerate-enumitem">read 8 bits as unsigned integer for the floor number; save in vector
|
|---|
| 3847 | <span
|
|---|
| 3848 | class="cmtt-12">[vorbis</span><span
|
|---|
| 3849 | class="cmtt-12">_mapping</span><span
|
|---|
| 3850 | class="cmtt-12">_submap</span><span
|
|---|
| 3851 | class="cmtt-12">_floor] </span>element <span
|
|---|
| 3852 | class="cmtt-12">[j]</span>
|
|---|
| 3853 | </dd><dt class="enumerate-enumitem">
|
|---|
| 3854 | C. </dt><dd
|
|---|
| 3855 | class="enumerate-enumitem">verify the floor number is not greater than the highest number floor
|
|---|
| 3856 | configured for the bitstream. If it is, the bitstream is undecodable
|
|---|
| 3857 | </dd><dt class="enumerate-enumitem">
|
|---|
| 3858 | D. </dt><dd
|
|---|
| 3859 | class="enumerate-enumitem">read 8 bits as unsigned integer for the residue number; save in vector
|
|---|
| 3860 | <span
|
|---|
| 3861 | class="cmtt-12">[vorbis</span><span
|
|---|
| 3862 | class="cmtt-12">_mapping</span><span
|
|---|
| 3863 | class="cmtt-12">_submap</span><span
|
|---|
| 3864 | class="cmtt-12">_residue] </span>element <span
|
|---|
| 3865 | class="cmtt-12">[j]</span>
|
|---|
| 3866 | </dd><dt class="enumerate-enumitem">
|
|---|
| 3867 | E. </dt><dd
|
|---|
| 3868 | class="enumerate-enumitem">verify the residue number is not greater than the highest number residue
|
|---|
| 3869 | configured for the bitstream. If it is, the bitstream is undecodable</dd></dl>
|
|---|
| 3870 | </dd><dt class="enumerate-enumitem">
|
|---|
| 3871 | vi. </dt><dd
|
|---|
| 3872 | class="enumerate-enumitem">save this mapping configuration in slot <span
|
|---|
| 3873 | class="cmtt-12">[i] </span>of the mapping configuration array
|
|---|
| 3874 | <span
|
|---|
| 3875 | class="cmtt-12">[vorbis</span><span
|
|---|
| 3876 | class="cmtt-12">_mapping</span><span
|
|---|
| 3877 | class="cmtt-12">_configurations]</span>.</dd></dl>
|
|---|
| 3878 | </dd></dl>
|
|---|
| 3879 |
|
|---|
| 3880 |
|
|---|
| 3881 |
|
|---|
| 3882 | </dd></dl>
|
|---|
| 3883 | <!--l. 246--><p class="noindent" ><span class="paragraphHead"><a
|
|---|
| 3884 | id="x1-710004.2.4"></a><span
|
|---|
| 3885 | class="cmbx-12">Modes</span></span>
|
|---|
| 3886 | <dl class="enumerate-enumitem"><dt class="enumerate-enumitem">
|
|---|
| 3887 | 1. </dt><dd
|
|---|
| 3888 | class="enumerate-enumitem"><span
|
|---|
| 3889 | class="cmtt-12">[vorbis</span><span
|
|---|
| 3890 | class="cmtt-12">_mode</span><span
|
|---|
| 3891 | class="cmtt-12">_count] </span>= read 6 bits as unsigned integer and add one
|
|---|
| 3892 | </dd><dt class="enumerate-enumitem">
|
|---|
| 3893 | 2. </dt><dd
|
|---|
| 3894 | class="enumerate-enumitem">For each of <span
|
|---|
| 3895 | class="cmtt-12">[vorbis</span><span
|
|---|
| 3896 | class="cmtt-12">_mode</span><span
|
|---|
| 3897 | class="cmtt-12">_count] </span>mode numbers:
|
|---|
| 3898 | <dl class="enumerate-enumitem"><dt class="enumerate-enumitem">
|
|---|
| 3899 | a) </dt><dd
|
|---|
| 3900 | class="enumerate-enumitem"><span
|
|---|
| 3901 | class="cmtt-12">[vorbis</span><span
|
|---|
| 3902 | class="cmtt-12">_mode</span><span
|
|---|
| 3903 | class="cmtt-12">_blockflag] </span>= read 1 bit
|
|---|
| 3904 | </dd><dt class="enumerate-enumitem">
|
|---|
| 3905 | b) </dt><dd
|
|---|
| 3906 | class="enumerate-enumitem"><span
|
|---|
| 3907 | class="cmtt-12">[vorbis</span><span
|
|---|
| 3908 | class="cmtt-12">_mode</span><span
|
|---|
| 3909 | class="cmtt-12">_windowtype] </span>= read 16 bits as unsigned integer
|
|---|
| 3910 | </dd><dt class="enumerate-enumitem">
|
|---|
| 3911 | c) </dt><dd
|
|---|
| 3912 | class="enumerate-enumitem"><span
|
|---|
| 3913 | class="cmtt-12">[vorbis</span><span
|
|---|
| 3914 | class="cmtt-12">_mode</span><span
|
|---|
| 3915 | class="cmtt-12">_transformtype] </span>= read 16 bits as unsigned integer
|
|---|
| 3916 | </dd><dt class="enumerate-enumitem">
|
|---|
| 3917 | d) </dt><dd
|
|---|
| 3918 | class="enumerate-enumitem"><span
|
|---|
| 3919 | class="cmtt-12">[vorbis</span><span
|
|---|
| 3920 | class="cmtt-12">_mode</span><span
|
|---|
| 3921 | class="cmtt-12">_mapping] </span>= read 8 bits as unsigned integer
|
|---|
| 3922 | </dd><dt class="enumerate-enumitem">
|
|---|
| 3923 | e) </dt><dd
|
|---|
| 3924 | class="enumerate-enumitem">verify ranges; zero is the only legal value in
|
|---|
| 3925 | Vorbis I for <span
|
|---|
| 3926 | class="cmtt-12">[vorbis</span><span
|
|---|
| 3927 | class="cmtt-12">_mode</span><span
|
|---|
| 3928 | class="cmtt-12">_windowtype] </span>and <span
|
|---|
| 3929 | class="cmtt-12">[vorbis</span><span
|
|---|
| 3930 | class="cmtt-12">_mode</span><span
|
|---|
| 3931 | class="cmtt-12">_transformtype]</span>.
|
|---|
| 3932 | <span
|
|---|
| 3933 | class="cmtt-12">[vorbis</span><span
|
|---|
| 3934 | class="cmtt-12">_mode</span><span
|
|---|
| 3935 | class="cmtt-12">_mapping] </span>must not be greater than the highest number mapping
|
|---|
| 3936 | in use. Any illegal values render the stream undecodable.
|
|---|
| 3937 | </dd><dt class="enumerate-enumitem">
|
|---|
| 3938 | f) </dt><dd
|
|---|
| 3939 | class="enumerate-enumitem">save this mode configuration in slot <span
|
|---|
| 3940 | class="cmtt-12">[i] </span>of the mode configuration array
|
|---|
| 3941 | <span
|
|---|
| 3942 | class="cmtt-12">[vorbis</span><span
|
|---|
| 3943 | class="cmtt-12">_mode</span><span
|
|---|
| 3944 | class="cmtt-12">_configurations]</span>.</dd></dl>
|
|---|
| 3945 | </dd><dt class="enumerate-enumitem">
|
|---|
| 3946 | 3. </dt><dd
|
|---|
| 3947 | class="enumerate-enumitem">read 1 bit as a framing flag. If unset, a framing error occurred and the stream is not
|
|---|
| 3948 | decodable.</dd></dl>
|
|---|
| 3949 | <!--l. 267--><p class="noindent" >After reading mode descriptions, setup header decode is complete.
|
|---|
| 3950 | <!--l. 276--><p class="noindent" >
|
|---|
| 3951 | <h4 class="subsectionHead"><span class="titlemark">4.3. </span> <a
|
|---|
| 3952 | id="x1-720004.3"></a>Audio packet decode and synthesis</h4>
|
|---|
| 3953 |
|
|---|
| 3954 |
|
|---|
| 3955 |
|
|---|
| 3956 | <!--l. 278--><p class="noindent" >Following the three header packets, all packets in a Vorbis I stream are audio. The first step of
|
|---|
| 3957 | audio packet decode is to read and verify the packet type. <span
|
|---|
| 3958 | class="cmti-12">A non-audio packet when audio is</span>
|
|---|
| 3959 | <span
|
|---|
| 3960 | class="cmti-12">expected indicates stream corruption or a non-compliant stream. The decoder must ignore the</span>
|
|---|
| 3961 | <span
|
|---|
| 3962 | class="cmti-12">packet and not attempt decoding it to audio</span>.
|
|---|
| 3963 | <!--l. 285--><p class="noindent" >
|
|---|
| 3964 | <h5 class="subsubsectionHead"><span class="titlemark">4.3.1. </span> <a
|
|---|
| 3965 | id="x1-730004.3.1"></a>packet type, mode and window decode</h5>
|
|---|
| 3966 | <!--l. 288--><p class="noindent" >
|
|---|
| 3967 | <dl class="enumerate-enumitem"><dt class="enumerate-enumitem">
|
|---|
| 3968 | 1. </dt><dd
|
|---|
| 3969 | class="enumerate-enumitem">read 1 bit <span
|
|---|
| 3970 | class="cmtt-12">[packet</span><span
|
|---|
| 3971 | class="cmtt-12">_type]</span>; check that packet type is 0 (audio)
|
|---|
| 3972 | </dd><dt class="enumerate-enumitem">
|
|---|
| 3973 | 2. </dt><dd
|
|---|
| 3974 | class="enumerate-enumitem">read <a
|
|---|
| 3975 | href="#x1-1190009.2.1">ilog</a>([vorbis_mode_count]-1) bits <span
|
|---|
| 3976 | class="cmtt-12">[mode</span><span
|
|---|
| 3977 | class="cmtt-12">_number]</span>
|
|---|
| 3978 | </dd><dt class="enumerate-enumitem">
|
|---|
| 3979 | 3. </dt><dd
|
|---|
| 3980 | class="enumerate-enumitem">decode blocksize <span
|
|---|
| 3981 | class="cmtt-12">[n] </span>is equal to <span
|
|---|
| 3982 | class="cmtt-12">[blocksize</span><span
|
|---|
| 3983 | class="cmtt-12">_0] </span>if <span
|
|---|
| 3984 | class="cmtt-12">[vorbis</span><span
|
|---|
| 3985 | class="cmtt-12">_mode</span><span
|
|---|
| 3986 | class="cmtt-12">_blockflag] </span>is 0,
|
|---|
| 3987 | else <span
|
|---|
| 3988 | class="cmtt-12">[n] </span>is equal to <span
|
|---|
| 3989 | class="cmtt-12">[blocksize</span><span
|
|---|
| 3990 | class="cmtt-12">_1]</span>.
|
|---|
| 3991 | </dd><dt class="enumerate-enumitem">
|
|---|
| 3992 | 4. </dt><dd
|
|---|
| 3993 | class="enumerate-enumitem">perform window selection and setup; this window is used later by the inverse
|
|---|
| 3994 | MDCT:
|
|---|
| 3995 | <dl class="enumerate-enumitem"><dt class="enumerate-enumitem">
|
|---|
| 3996 | a) </dt><dd
|
|---|
| 3997 | class="enumerate-enumitem">if this is a long window (the <span
|
|---|
| 3998 | class="cmtt-12">[vorbis</span><span
|
|---|
| 3999 | class="cmtt-12">_mode</span><span
|
|---|
| 4000 | class="cmtt-12">_blockflag] </span>flag of this mode is
|
|---|
| 4001 | set):
|
|---|
| 4002 | <dl class="enumerate-enumitem"><dt class="enumerate-enumitem">
|
|---|
| 4003 | i. </dt><dd
|
|---|
| 4004 | class="enumerate-enumitem">read 1 bit for <span
|
|---|
| 4005 | class="cmtt-12">[previous</span><span
|
|---|
| 4006 | class="cmtt-12">_window</span><span
|
|---|
| 4007 | class="cmtt-12">_flag]</span>
|
|---|
| 4008 | </dd><dt class="enumerate-enumitem">
|
|---|
| 4009 | ii. </dt><dd
|
|---|
| 4010 | class="enumerate-enumitem">read 1 bit for <span
|
|---|
| 4011 | class="cmtt-12">[next</span><span
|
|---|
| 4012 | class="cmtt-12">_window</span><span
|
|---|
| 4013 | class="cmtt-12">_flag]</span>
|
|---|
| 4014 | </dd><dt class="enumerate-enumitem">
|
|---|
| 4015 | iii. </dt><dd
|
|---|
| 4016 | class="enumerate-enumitem">if <span
|
|---|
| 4017 | class="cmtt-12">[previous</span><span
|
|---|
| 4018 | class="cmtt-12">_window</span><span
|
|---|
| 4019 | class="cmtt-12">_flag] </span>is not set, the left half of the window will
|
|---|
| 4020 | be a hybrid window for lapping with a short block. See <a
|
|---|
| 4021 | href="#paragraph.1" >paragraph <a
|
|---|
| 4022 | href="#x1-260001.3.2">1.3.2</a></a>,
|
|---|
| 4023 | “<a
|
|---|
| 4024 | href="#x1-260001.3.2">Window shape decode (long windows only)<!--tex4ht:ref: vorbis:spec:window --></a>” for an illustration of
|
|---|
| 4025 | overlapping dissimilar windows. Else, the left half window will have normal
|
|---|
| 4026 | long shape.
|
|---|
| 4027 | </dd><dt class="enumerate-enumitem">
|
|---|
| 4028 | iv. </dt><dd
|
|---|
| 4029 | class="enumerate-enumitem">if <span
|
|---|
| 4030 | class="cmtt-12">[next</span><span
|
|---|
| 4031 | class="cmtt-12">_window</span><span
|
|---|
| 4032 | class="cmtt-12">_flag] </span>is not set, the right half of the window will be
|
|---|
| 4033 | a hybrid window for lapping with a short block. See <a
|
|---|
| 4034 | href="#x1-260001.3.2">paragraph 1.3.2</a>,
|
|---|
| 4035 |
|
|---|
| 4036 |
|
|---|
| 4037 |
|
|---|
| 4038 | “<a
|
|---|
| 4039 | href="#x1-260001.3.2">Window shape decode (long windows only)<!--tex4ht:ref: vorbis:spec:window --></a>” for an illustration of
|
|---|
| 4040 | overlapping dissimilar windows. Else, the left right window will have normal
|
|---|
| 4041 | long shape.</dd></dl>
|
|---|
| 4042 | </dd><dt class="enumerate-enumitem">
|
|---|
| 4043 | b) </dt><dd
|
|---|
| 4044 | class="enumerate-enumitem">if this is a short window, the window is always the same short-window
|
|---|
| 4045 | shape.</dd></dl>
|
|---|
| 4046 | </dd></dl>
|
|---|
| 4047 | <!--l. 320--><p class="noindent" >Vorbis windows all use the slope function <span
|
|---|
| 4048 | class="cmmi-12">y </span>= sin(<img
|
|---|
| 4049 | src="Vorbis_I_spec1x.png" alt="π
|
|---|
| 4050 | 2" class="frac" align="middle"> <span
|
|---|
| 4051 | class="cmsy-10x-x-120">*</span> sin <sup><span
|
|---|
| 4052 | class="cmr-8">2</span></sup>((<span
|
|---|
| 4053 | class="cmmi-12">x </span>+ 0<span
|
|---|
| 4054 | class="cmmi-12">.</span>5)<span
|
|---|
| 4055 | class="cmmi-12">∕n </span><span
|
|---|
| 4056 | class="cmsy-10x-x-120">* </span><span
|
|---|
| 4057 | class="cmmi-12">π</span>)), where <span
|
|---|
| 4058 | class="cmmi-12">n </span>is window
|
|---|
| 4059 | size and <span
|
|---|
| 4060 | class="cmmi-12">x </span>ranges 0<span
|
|---|
| 4061 | class="cmmi-12">…</span><span
|
|---|
| 4062 | class="cmmi-12">n</span><span
|
|---|
| 4063 | class="cmsy-10x-x-120">- </span>1, but dissimilar lapping requirements can affect overall shape. Window
|
|---|
| 4064 | generation proceeds as follows:
|
|---|
| 4065 | <!--l. 326--><p class="noindent" >
|
|---|
| 4066 | <dl class="enumerate-enumitem"><dt class="enumerate-enumitem">
|
|---|
| 4067 | 1. </dt><dd
|
|---|
| 4068 | class="enumerate-enumitem"><span
|
|---|
| 4069 | class="cmtt-12">[window</span><span
|
|---|
| 4070 | class="cmtt-12">_center] </span>= <span
|
|---|
| 4071 | class="cmtt-12">[n] </span>/ 2
|
|---|
| 4072 | </dd><dt class="enumerate-enumitem">
|
|---|
| 4073 | 2. </dt><dd
|
|---|
| 4074 | class="enumerate-enumitem">if (<span
|
|---|
| 4075 | class="cmtt-12">[vorbis</span><span
|
|---|
| 4076 | class="cmtt-12">_mode</span><span
|
|---|
| 4077 | class="cmtt-12">_blockflag] </span>is set and <span
|
|---|
| 4078 | class="cmtt-12">[previous</span><span
|
|---|
| 4079 | class="cmtt-12">_window</span><span
|
|---|
| 4080 | class="cmtt-12">_flag] </span>is not set)
|
|---|
| 4081 | then
|
|---|
| 4082 | <dl class="enumerate-enumitem"><dt class="enumerate-enumitem">
|
|---|
| 4083 | a) </dt><dd
|
|---|
| 4084 | class="enumerate-enumitem"><span
|
|---|
| 4085 | class="cmtt-12">[left</span><span
|
|---|
| 4086 | class="cmtt-12">_window</span><span
|
|---|
| 4087 | class="cmtt-12">_start] </span>= <span
|
|---|
| 4088 | class="cmtt-12">[n]</span>/4 - <span
|
|---|
| 4089 | class="cmtt-12">[blocksize</span><span
|
|---|
| 4090 | class="cmtt-12">_0]</span>/4
|
|---|
| 4091 | </dd><dt class="enumerate-enumitem">
|
|---|
| 4092 | b) </dt><dd
|
|---|
| 4093 | class="enumerate-enumitem"><span
|
|---|
| 4094 | class="cmtt-12">[left</span><span
|
|---|
| 4095 | class="cmtt-12">_window</span><span
|
|---|
| 4096 | class="cmtt-12">_end] </span>= <span
|
|---|
| 4097 | class="cmtt-12">[n]</span>/4 + <span
|
|---|
| 4098 | class="cmtt-12">[blocksize</span><span
|
|---|
| 4099 | class="cmtt-12">_0]</span>/4
|
|---|
| 4100 | </dd><dt class="enumerate-enumitem">
|
|---|
| 4101 | c) </dt><dd
|
|---|
| 4102 | class="enumerate-enumitem"><span
|
|---|
| 4103 | class="cmtt-12">[left</span><span
|
|---|
| 4104 | class="cmtt-12">_n] </span>= <span
|
|---|
| 4105 | class="cmtt-12">[blocksize</span><span
|
|---|
| 4106 | class="cmtt-12">_0]</span>/2</dd></dl>
|
|---|
| 4107 | <!--l. 335--><p class="noindent" >else
|
|---|
| 4108 | <dl class="enumerate-enumitem"><dt class="enumerate-enumitem">
|
|---|
| 4109 | a) </dt><dd
|
|---|
| 4110 | class="enumerate-enumitem"><span
|
|---|
| 4111 | class="cmtt-12">[left</span><span
|
|---|
| 4112 | class="cmtt-12">_window</span><span
|
|---|
| 4113 | class="cmtt-12">_start] </span>= 0
|
|---|
| 4114 | </dd><dt class="enumerate-enumitem">
|
|---|
| 4115 | b) </dt><dd
|
|---|
| 4116 | class="enumerate-enumitem"><span
|
|---|
| 4117 | class="cmtt-12">[left</span><span
|
|---|
| 4118 | class="cmtt-12">_window</span><span
|
|---|
| 4119 | class="cmtt-12">_end] </span>= <span
|
|---|
| 4120 | class="cmtt-12">[window</span><span
|
|---|
| 4121 | class="cmtt-12">_center]</span>
|
|---|
| 4122 | </dd><dt class="enumerate-enumitem">
|
|---|
| 4123 | c) </dt><dd
|
|---|
| 4124 | class="enumerate-enumitem"><span
|
|---|
| 4125 | class="cmtt-12">[left</span><span
|
|---|
| 4126 | class="cmtt-12">_n] </span>= <span
|
|---|
| 4127 | class="cmtt-12">[n]</span>/2</dd></dl>
|
|---|
| 4128 | </dd><dt class="enumerate-enumitem">
|
|---|
| 4129 | 3. </dt><dd
|
|---|
| 4130 | class="enumerate-enumitem">if (<span
|
|---|
| 4131 | class="cmtt-12">[vorbis</span><span
|
|---|
| 4132 | class="cmtt-12">_mode</span><span
|
|---|
| 4133 | class="cmtt-12">_blockflag] </span>is set and <span
|
|---|
| 4134 | class="cmtt-12">[next</span><span
|
|---|
| 4135 | class="cmtt-12">_window</span><span
|
|---|
| 4136 | class="cmtt-12">_flag] </span>is not set) then
|
|---|
| 4137 | <dl class="enumerate-enumitem"><dt class="enumerate-enumitem">
|
|---|
| 4138 | a) </dt><dd
|
|---|
| 4139 | class="enumerate-enumitem"><span
|
|---|
| 4140 | class="cmtt-12">[right</span><span
|
|---|
| 4141 | class="cmtt-12">_window</span><span
|
|---|
| 4142 | class="cmtt-12">_start] </span>= <span
|
|---|
| 4143 | class="cmtt-12">[n]*3</span>/4 - <span
|
|---|
| 4144 | class="cmtt-12">[blocksize</span><span
|
|---|
| 4145 | class="cmtt-12">_0]</span>/4
|
|---|
| 4146 | </dd><dt class="enumerate-enumitem">
|
|---|
| 4147 | b) </dt><dd
|
|---|
| 4148 | class="enumerate-enumitem"><span
|
|---|
| 4149 | class="cmtt-12">[right</span><span
|
|---|
| 4150 | class="cmtt-12">_window</span><span
|
|---|
| 4151 | class="cmtt-12">_end] </span>= <span
|
|---|
| 4152 | class="cmtt-12">[n]*3</span>/4 + <span
|
|---|
| 4153 | class="cmtt-12">[blocksize</span><span
|
|---|
| 4154 | class="cmtt-12">_0]</span>/4
|
|---|
| 4155 |
|
|---|
| 4156 |
|
|---|
| 4157 |
|
|---|
| 4158 | </dd><dt class="enumerate-enumitem">
|
|---|
| 4159 | c) </dt><dd
|
|---|
| 4160 | class="enumerate-enumitem"><span
|
|---|
| 4161 | class="cmtt-12">[right</span><span
|
|---|
| 4162 | class="cmtt-12">_n] </span>= <span
|
|---|
| 4163 | class="cmtt-12">[blocksize</span><span
|
|---|
| 4164 | class="cmtt-12">_0]</span>/2</dd></dl>
|
|---|
| 4165 | <!--l. 351--><p class="noindent" >else
|
|---|
| 4166 | <dl class="enumerate-enumitem"><dt class="enumerate-enumitem">
|
|---|
| 4167 | a) </dt><dd
|
|---|
| 4168 | class="enumerate-enumitem"><span
|
|---|
| 4169 | class="cmtt-12">[right</span><span
|
|---|
| 4170 | class="cmtt-12">_window</span><span
|
|---|
| 4171 | class="cmtt-12">_start] </span>= <span
|
|---|
| 4172 | class="cmtt-12">[window</span><span
|
|---|
| 4173 | class="cmtt-12">_center]</span>
|
|---|
| 4174 | </dd><dt class="enumerate-enumitem">
|
|---|
| 4175 | b) </dt><dd
|
|---|
| 4176 | class="enumerate-enumitem"><span
|
|---|
| 4177 | class="cmtt-12">[right</span><span
|
|---|
| 4178 | class="cmtt-12">_window</span><span
|
|---|
| 4179 | class="cmtt-12">_end] </span>= <span
|
|---|
| 4180 | class="cmtt-12">[n]</span>
|
|---|
| 4181 | </dd><dt class="enumerate-enumitem">
|
|---|
| 4182 | c) </dt><dd
|
|---|
| 4183 | class="enumerate-enumitem"><span
|
|---|
| 4184 | class="cmtt-12">[right</span><span
|
|---|
| 4185 | class="cmtt-12">_n] </span>= <span
|
|---|
| 4186 | class="cmtt-12">[n]</span>/2</dd></dl>
|
|---|
| 4187 | </dd><dt class="enumerate-enumitem">
|
|---|
| 4188 | 4. </dt><dd
|
|---|
| 4189 | class="enumerate-enumitem">window from range 0 ... <span
|
|---|
| 4190 | class="cmtt-12">[left</span><span
|
|---|
| 4191 | class="cmtt-12">_window</span><span
|
|---|
| 4192 | class="cmtt-12">_start]</span>-1 inclusive is zero
|
|---|
| 4193 | </dd><dt class="enumerate-enumitem">
|
|---|
| 4194 | 5. </dt><dd
|
|---|
| 4195 | class="enumerate-enumitem">for <span
|
|---|
| 4196 | class="cmtt-12">[i] </span>in range <span
|
|---|
| 4197 | class="cmtt-12">[left</span><span
|
|---|
| 4198 | class="cmtt-12">_window</span><span
|
|---|
| 4199 | class="cmtt-12">_start] </span>... <span
|
|---|
| 4200 | class="cmtt-12">[left</span><span
|
|---|
| 4201 | class="cmtt-12">_window</span><span
|
|---|
| 4202 | class="cmtt-12">_end]</span>-1, window(<span
|
|---|
| 4203 | class="cmtt-12">[i]</span>) =
|
|---|
| 4204 | sin(<img
|
|---|
| 4205 | src="Vorbis_I_spec2x.png" alt="π
|
|---|
| 4206 | 2" class="frac" align="middle"> <span
|
|---|
| 4207 | class="cmsy-10x-x-120">*</span> sin <sup><span
|
|---|
| 4208 | class="cmr-8">2</span></sup>( (<span
|
|---|
| 4209 | class="cmtt-12">[i]</span>-<span
|
|---|
| 4210 | class="cmtt-12">[left</span><span
|
|---|
| 4211 | class="cmtt-12">_window</span><span
|
|---|
| 4212 | class="cmtt-12">_start]</span>+0.5) / <span
|
|---|
| 4213 | class="cmtt-12">[left</span><span
|
|---|
| 4214 | class="cmtt-12">_n] </span><span
|
|---|
| 4215 | class="cmsy-10x-x-120">*</span><img
|
|---|
| 4216 | src="Vorbis_I_spec3x.png" alt="π
|
|---|
| 4217 | 2" class="frac" align="middle">) )
|
|---|
| 4218 | </dd><dt class="enumerate-enumitem">
|
|---|
| 4219 | 6. </dt><dd
|
|---|
| 4220 | class="enumerate-enumitem">window from range <span
|
|---|
| 4221 | class="cmtt-12">[left</span><span
|
|---|
| 4222 | class="cmtt-12">_window</span><span
|
|---|
| 4223 | class="cmtt-12">_end] </span>... <span
|
|---|
| 4224 | class="cmtt-12">[right</span><span
|
|---|
| 4225 | class="cmtt-12">_window</span><span
|
|---|
| 4226 | class="cmtt-12">_start]</span>-1 inclusive is
|
|---|
| 4227 | one
|
|---|
| 4228 | </dd><dt class="enumerate-enumitem">
|
|---|
| 4229 | 7. </dt><dd
|
|---|
| 4230 | class="enumerate-enumitem">for <span
|
|---|
| 4231 | class="cmtt-12">[i] </span>in range <span
|
|---|
| 4232 | class="cmtt-12">[right</span><span
|
|---|
| 4233 | class="cmtt-12">_window</span><span
|
|---|
| 4234 | class="cmtt-12">_start] </span>... <span
|
|---|
| 4235 | class="cmtt-12">[right</span><span
|
|---|
| 4236 | class="cmtt-12">_window</span><span
|
|---|
| 4237 | class="cmtt-12">_end]</span>-1, window(<span
|
|---|
| 4238 | class="cmtt-12">[i]</span>) =
|
|---|
| 4239 | sin(<img
|
|---|
| 4240 | src="Vorbis_I_spec4x.png" alt="π2" class="frac" align="middle"> <span
|
|---|
| 4241 | class="cmsy-10x-x-120">*</span> sin <sup><span
|
|---|
| 4242 | class="cmr-8">2</span></sup>( (<span
|
|---|
| 4243 | class="cmtt-12">[i]</span>-<span
|
|---|
| 4244 | class="cmtt-12">[right</span><span
|
|---|
| 4245 | class="cmtt-12">_window</span><span
|
|---|
| 4246 | class="cmtt-12">_start]</span>+0.5) / <span
|
|---|
| 4247 | class="cmtt-12">[right</span><span
|
|---|
| 4248 | class="cmtt-12">_n] </span><span
|
|---|
| 4249 | class="cmsy-10x-x-120">*</span><img
|
|---|
| 4250 | src="Vorbis_I_spec5x.png" alt="π2" class="frac" align="middle"> + <img
|
|---|
| 4251 | src="Vorbis_I_spec6x.png" alt="π2" class="frac" align="middle">) )
|
|---|
| 4252 | </dd><dt class="enumerate-enumitem">
|
|---|
| 4253 | 8. </dt><dd
|
|---|
| 4254 | class="enumerate-enumitem">window from range <span
|
|---|
| 4255 | class="cmtt-12">[right</span><span
|
|---|
| 4256 | class="cmtt-12">_window</span><span
|
|---|
| 4257 | class="cmtt-12">_start] </span>... <span
|
|---|
| 4258 | class="cmtt-12">[n]</span>-1 is zero</dd></dl>
|
|---|
| 4259 | <!--l. 367--><p class="noindent" >An end-of-packet condition up to this point should be considered an error that discards this
|
|---|
| 4260 | packet from the stream. An end of packet condition past this point is to be considered a possible
|
|---|
| 4261 | nominal occurrence.
|
|---|
| 4262 | <!--l. 374--><p class="noindent" >
|
|---|
| 4263 | <h5 class="subsubsectionHead"><span class="titlemark">4.3.2. </span> <a
|
|---|
| 4264 | id="x1-740004.3.2"></a>floor curve decode</h5>
|
|---|
| 4265 | <!--l. 376--><p class="noindent" >From this point on, we assume out decode context is using mode number <span
|
|---|
| 4266 | class="cmtt-12">[mode</span><span
|
|---|
| 4267 | class="cmtt-12">_number]</span>
|
|---|
| 4268 | from configuration array <span
|
|---|
| 4269 | class="cmtt-12">[vorbis</span><span
|
|---|
| 4270 | class="cmtt-12">_mode</span><span
|
|---|
| 4271 | class="cmtt-12">_configurations] </span>and the map number
|
|---|
| 4272 | <span
|
|---|
| 4273 | class="cmtt-12">[vorbis</span><span
|
|---|
| 4274 | class="cmtt-12">_mode</span><span
|
|---|
| 4275 | class="cmtt-12">_mapping] </span>(specified by the current mode) taken from the mapping configuration
|
|---|
| 4276 | array <span
|
|---|
| 4277 | class="cmtt-12">[vorbis</span><span
|
|---|
| 4278 | class="cmtt-12">_mapping</span><span
|
|---|
| 4279 | class="cmtt-12">_configurations]</span>.
|
|---|
| 4280 | <!--l. 383--><p class="noindent" >Floor curves are decoded one-by-one in channel order.
|
|---|
| 4281 |
|
|---|
| 4282 |
|
|---|
| 4283 |
|
|---|
| 4284 | <!--l. 385--><p class="noindent" >For each floor <span
|
|---|
| 4285 | class="cmtt-12">[i] </span>of <span
|
|---|
| 4286 | class="cmtt-12">[audio</span><span
|
|---|
| 4287 | class="cmtt-12">_channels]</span>
|
|---|
| 4288 | <dl class="enumerate-enumitem"><dt class="enumerate-enumitem">
|
|---|
| 4289 | 1. </dt><dd
|
|---|
| 4290 | class="enumerate-enumitem"><span
|
|---|
| 4291 | class="cmtt-12">[submap</span><span
|
|---|
| 4292 | class="cmtt-12">_number] </span>= element <span
|
|---|
| 4293 | class="cmtt-12">[i] </span>of vector [vorbis_mapping_mux]
|
|---|
| 4294 | </dd><dt class="enumerate-enumitem">
|
|---|
| 4295 | 2. </dt><dd
|
|---|
| 4296 | class="enumerate-enumitem"><span
|
|---|
| 4297 | class="cmtt-12">[floor</span><span
|
|---|
| 4298 | class="cmtt-12">_number] </span>= element <span
|
|---|
| 4299 | class="cmtt-12">[submap</span><span
|
|---|
| 4300 | class="cmtt-12">_number] </span>of vector [vorbis_submap_floor]
|
|---|
| 4301 | </dd><dt class="enumerate-enumitem">
|
|---|
| 4302 | 3. </dt><dd
|
|---|
| 4303 | class="enumerate-enumitem">if the floor type of this floor (vector
|
|---|
| 4304 | <span
|
|---|
| 4305 | class="cmtt-12">[vorbis</span><span
|
|---|
| 4306 | class="cmtt-12">_floor</span><span
|
|---|
| 4307 | class="cmtt-12">_types] </span>element <span
|
|---|
| 4308 | class="cmtt-12">[floor</span><span
|
|---|
| 4309 | class="cmtt-12">_number]</span>) is zero then decode the floor for
|
|---|
| 4310 | channel <span
|
|---|
| 4311 | class="cmtt-12">[i] </span>according to the <a
|
|---|
| 4312 | href="#x1-940006.2.2">subsubsection 6.2.2</a>, “<a
|
|---|
| 4313 | href="#x1-940006.2.2">packet decode<!--tex4ht:ref: vorbis:spec:floor0-decode --></a>”
|
|---|
| 4314 | </dd><dt class="enumerate-enumitem">
|
|---|
| 4315 | 4. </dt><dd
|
|---|
| 4316 | class="enumerate-enumitem">if the type of this floor is one then decode the floor for channel <span
|
|---|
| 4317 | class="cmtt-12">[i] </span>according to the
|
|---|
| 4318 | <a
|
|---|
| 4319 | href="#x1-1020007.2.3">subsubsection 7.2.3</a>, “<a
|
|---|
| 4320 | href="#x1-1020007.2.3">packet decode<!--tex4ht:ref: vorbis:spec:floor1-decode --></a>”
|
|---|
| 4321 | </dd><dt class="enumerate-enumitem">
|
|---|
| 4322 | 5. </dt><dd
|
|---|
| 4323 | class="enumerate-enumitem">save the needed decoded floor information for channel for later synthesis
|
|---|
| 4324 | </dd><dt class="enumerate-enumitem">
|
|---|
| 4325 | 6. </dt><dd
|
|---|
| 4326 | class="enumerate-enumitem">if the decoded floor returned ’unused’, set vector <span
|
|---|
| 4327 | class="cmtt-12">[no</span><span
|
|---|
| 4328 | class="cmtt-12">_residue] </span>element <span
|
|---|
| 4329 | class="cmtt-12">[i] </span>to true,
|
|---|
| 4330 | else set vector <span
|
|---|
| 4331 | class="cmtt-12">[no</span><span
|
|---|
| 4332 | class="cmtt-12">_residue] </span>element <span
|
|---|
| 4333 | class="cmtt-12">[i] </span>to false</dd></dl>
|
|---|
| 4334 | <!--l. 405--><p class="noindent" >An end-of-packet condition during floor decode shall result in packet decode zeroing all channel
|
|---|
| 4335 | output vectors and skipping to the add/overlap output stage.
|
|---|
| 4336 | <!--l. 411--><p class="noindent" >
|
|---|
| 4337 | <h5 class="subsubsectionHead"><span class="titlemark">4.3.3. </span> <a
|
|---|
| 4338 | id="x1-750004.3.3"></a>nonzero vector propagate</h5>
|
|---|
| 4339 | <!--l. 413--><p class="noindent" >A possible result of floor decode is that a specific vector is marked ’unused’ which indicates that
|
|---|
| 4340 | that final output vector is all-zero values (and the floor is zero). The residue for that vector is not
|
|---|
| 4341 | coded in the stream, save for one complication. If some vectors are used and some are not,
|
|---|
| 4342 | channel coupling could result in mixing a zeroed and nonzeroed vector to produce two nonzeroed
|
|---|
| 4343 | vectors.
|
|---|
| 4344 | <!--l. 420--><p class="noindent" >for each <span
|
|---|
| 4345 | class="cmtt-12">[i] </span>from 0 ... <span
|
|---|
| 4346 | class="cmtt-12">[vorbis</span><span
|
|---|
| 4347 | class="cmtt-12">_mapping</span><span
|
|---|
| 4348 | class="cmtt-12">_coupling</span><span
|
|---|
| 4349 | class="cmtt-12">_steps]</span>-1
|
|---|
| 4350 | <!--l. 423--><p class="noindent" >
|
|---|
| 4351 | <dl class="enumerate-enumitem"><dt class="enumerate-enumitem">
|
|---|
| 4352 | 1. </dt><dd
|
|---|
| 4353 | class="enumerate-enumitem">if either <span
|
|---|
| 4354 | class="cmtt-12">[no</span><span
|
|---|
| 4355 | class="cmtt-12">_residue] </span>entry for channel (<span
|
|---|
| 4356 | class="cmtt-12">[vorbis</span><span
|
|---|
| 4357 | class="cmtt-12">_mapping</span><span
|
|---|
| 4358 | class="cmtt-12">_magnitude] </span>element
|
|---|
| 4359 | <span
|
|---|
| 4360 | class="cmtt-12">[i]</span>) or channel (<span
|
|---|
| 4361 | class="cmtt-12">[vorbis</span><span
|
|---|
| 4362 | class="cmtt-12">_mapping</span><span
|
|---|
| 4363 | class="cmtt-12">_angle] </span>element <span
|
|---|
| 4364 | class="cmtt-12">[i]</span>) are set to false, then both
|
|---|
| 4365 | must be set to false. Note that an ’unused’ floor has no decoded floor information; it
|
|---|
| 4366 |
|
|---|
| 4367 |
|
|---|
| 4368 |
|
|---|
| 4369 | is important that this is remembered at floor curve synthesis time.</dd></dl>
|
|---|
| 4370 | <!--l. 435--><p class="noindent" >
|
|---|
| 4371 | <h5 class="subsubsectionHead"><span class="titlemark">4.3.4. </span> <a
|
|---|
| 4372 | id="x1-760004.3.4"></a>residue decode</h5>
|
|---|
| 4373 | <!--l. 437--><p class="noindent" >Unlike floors, which are decoded in channel order, the residue vectors are decoded in submap
|
|---|
| 4374 | order.
|
|---|
| 4375 | <!--l. 440--><p class="noindent" >for each submap <span
|
|---|
| 4376 | class="cmtt-12">[i] </span>in order from 0 ... <span
|
|---|
| 4377 | class="cmtt-12">[vorbis</span><span
|
|---|
| 4378 | class="cmtt-12">_mapping</span><span
|
|---|
| 4379 | class="cmtt-12">_submaps]</span>-1
|
|---|
| 4380 | <!--l. 443--><p class="noindent" >
|
|---|
| 4381 | <dl class="enumerate-enumitem"><dt class="enumerate-enumitem">
|
|---|
| 4382 | 1. </dt><dd
|
|---|
| 4383 | class="enumerate-enumitem"><span
|
|---|
| 4384 | class="cmtt-12">[ch] </span>= 0
|
|---|
| 4385 | </dd><dt class="enumerate-enumitem">
|
|---|
| 4386 | 2. </dt><dd
|
|---|
| 4387 | class="enumerate-enumitem">for each channel <span
|
|---|
| 4388 | class="cmtt-12">[j] </span>in order from 0 ... <span
|
|---|
| 4389 | class="cmtt-12">[audio</span><span
|
|---|
| 4390 | class="cmtt-12">_channels] </span>- 1
|
|---|
| 4391 | <dl class="enumerate-enumitem"><dt class="enumerate-enumitem">
|
|---|
| 4392 | a) </dt><dd
|
|---|
| 4393 | class="enumerate-enumitem">if channel <span
|
|---|
| 4394 | class="cmtt-12">[j] </span>in submap <span
|
|---|
| 4395 | class="cmtt-12">[i] </span>(vector <span
|
|---|
| 4396 | class="cmtt-12">[vorbis</span><span
|
|---|
| 4397 | class="cmtt-12">_mapping</span><span
|
|---|
| 4398 | class="cmtt-12">_mux] </span>element <span
|
|---|
| 4399 | class="cmtt-12">[j] </span>is equal to
|
|---|
| 4400 | <span
|
|---|
| 4401 | class="cmtt-12">[i]</span>)
|
|---|
| 4402 | <dl class="enumerate-enumitem"><dt class="enumerate-enumitem">
|
|---|
| 4403 | i. </dt><dd
|
|---|
| 4404 | class="enumerate-enumitem">if vector <span
|
|---|
| 4405 | class="cmtt-12">[no</span><span
|
|---|
| 4406 | class="cmtt-12">_residue] </span>element <span
|
|---|
| 4407 | class="cmtt-12">[j] </span>is true
|
|---|
| 4408 | <dl class="enumerate-enumitem"><dt class="enumerate-enumitem">
|
|---|
| 4409 | A. </dt><dd
|
|---|
| 4410 | class="enumerate-enumitem">vector <span
|
|---|
| 4411 | class="cmtt-12">[do</span><span
|
|---|
| 4412 | class="cmtt-12">_not</span><span
|
|---|
| 4413 | class="cmtt-12">_decode</span><span
|
|---|
| 4414 | class="cmtt-12">_flag] </span>element <span
|
|---|
| 4415 | class="cmtt-12">[ch] </span>is set</dd></dl>
|
|---|
| 4416 | <!--l. 452--><p class="noindent" >else
|
|---|
| 4417 | <dl class="enumerate-enumitem"><dt class="enumerate-enumitem">
|
|---|
| 4418 | A. </dt><dd
|
|---|
| 4419 | class="enumerate-enumitem">vector <span
|
|---|
| 4420 | class="cmtt-12">[do</span><span
|
|---|
| 4421 | class="cmtt-12">_not</span><span
|
|---|
| 4422 | class="cmtt-12">_decode</span><span
|
|---|
| 4423 | class="cmtt-12">_flag] </span>element <span
|
|---|
| 4424 | class="cmtt-12">[ch] </span>is unset</dd></dl>
|
|---|
| 4425 | </dd><dt class="enumerate-enumitem">
|
|---|
| 4426 | ii. </dt><dd
|
|---|
| 4427 | class="enumerate-enumitem">increment <span
|
|---|
| 4428 | class="cmtt-12">[ch]</span></dd></dl>
|
|---|
| 4429 | </dd></dl>
|
|---|
| 4430 | </dd><dt class="enumerate-enumitem">
|
|---|
| 4431 | 3. </dt><dd
|
|---|
| 4432 | class="enumerate-enumitem"><span
|
|---|
| 4433 | class="cmtt-12">[residue</span><span
|
|---|
| 4434 | class="cmtt-12">_number] </span>= vector <span
|
|---|
| 4435 | class="cmtt-12">[vorbis</span><span
|
|---|
| 4436 | class="cmtt-12">_mapping</span><span
|
|---|
| 4437 | class="cmtt-12">_submap</span><span
|
|---|
| 4438 | class="cmtt-12">_residue] </span>element <span
|
|---|
| 4439 | class="cmtt-12">[i]</span>
|
|---|
| 4440 | </dd><dt class="enumerate-enumitem">
|
|---|
| 4441 | 4. </dt><dd
|
|---|
| 4442 | class="enumerate-enumitem"><span
|
|---|
| 4443 | class="cmtt-12">[residue</span><span
|
|---|
| 4444 | class="cmtt-12">_type] </span>= vector <span
|
|---|
| 4445 | class="cmtt-12">[vorbis</span><span
|
|---|
| 4446 | class="cmtt-12">_residue</span><span
|
|---|
| 4447 | class="cmtt-12">_types] </span>element <span
|
|---|
| 4448 | class="cmtt-12">[residue</span><span
|
|---|
| 4449 | class="cmtt-12">_number]</span>
|
|---|
| 4450 | </dd><dt class="enumerate-enumitem">
|
|---|
| 4451 | 5. </dt><dd
|
|---|
| 4452 | class="enumerate-enumitem">decode <span
|
|---|
| 4453 | class="cmtt-12">[ch] </span>vectors using residue <span
|
|---|
| 4454 | class="cmtt-12">[residue</span><span
|
|---|
| 4455 | class="cmtt-12">_number]</span>, according to type <span
|
|---|
| 4456 | class="cmtt-12">[residue</span><span
|
|---|
| 4457 | class="cmtt-12">_type]</span>,
|
|---|
| 4458 |
|
|---|
| 4459 |
|
|---|
| 4460 |
|
|---|
| 4461 | also passing vector <span
|
|---|
| 4462 | class="cmtt-12">[do</span><span
|
|---|
| 4463 | class="cmtt-12">_not</span><span
|
|---|
| 4464 | class="cmtt-12">_decode</span><span
|
|---|
| 4465 | class="cmtt-12">_flag] </span>to indicate which vectors in the bundle should
|
|---|
| 4466 | not be decoded. Correct per-vector decode length is <span
|
|---|
| 4467 | class="cmtt-12">[n]</span>/2.
|
|---|
| 4468 | </dd><dt class="enumerate-enumitem">
|
|---|
| 4469 | 6. </dt><dd
|
|---|
| 4470 | class="enumerate-enumitem"><span
|
|---|
| 4471 | class="cmtt-12">[ch] </span>= 0
|
|---|
| 4472 | </dd><dt class="enumerate-enumitem">
|
|---|
| 4473 | 7. </dt><dd
|
|---|
| 4474 | class="enumerate-enumitem">for each channel <span
|
|---|
| 4475 | class="cmtt-12">[j] </span>in order from 0 ... <span
|
|---|
| 4476 | class="cmtt-12">[audio</span><span
|
|---|
| 4477 | class="cmtt-12">_channels]</span>
|
|---|
| 4478 | <dl class="enumerate-enumitem"><dt class="enumerate-enumitem">
|
|---|
| 4479 | a) </dt><dd
|
|---|
| 4480 | class="enumerate-enumitem">if channel <span
|
|---|
| 4481 | class="cmtt-12">[j] </span>is in submap <span
|
|---|
| 4482 | class="cmtt-12">[i] </span>(vector <span
|
|---|
| 4483 | class="cmtt-12">[vorbis</span><span
|
|---|
| 4484 | class="cmtt-12">_mapping</span><span
|
|---|
| 4485 | class="cmtt-12">_mux] </span>element <span
|
|---|
| 4486 | class="cmtt-12">[j] </span>is equal
|
|---|
| 4487 | to <span
|
|---|
| 4488 | class="cmtt-12">[i]</span>)
|
|---|
| 4489 | <dl class="enumerate-enumitem"><dt class="enumerate-enumitem">
|
|---|
| 4490 | i. </dt><dd
|
|---|
| 4491 | class="enumerate-enumitem">residue vector for channel <span
|
|---|
| 4492 | class="cmtt-12">[j] </span>is set to decoded residue vector <span
|
|---|
| 4493 | class="cmtt-12">[ch]</span>
|
|---|
| 4494 | </dd><dt class="enumerate-enumitem">
|
|---|
| 4495 | ii. </dt><dd
|
|---|
| 4496 | class="enumerate-enumitem">increment <span
|
|---|
| 4497 | class="cmtt-12">[ch]</span></dd></dl>
|
|---|
| 4498 | </dd></dl>
|
|---|
| 4499 | </dd></dl>
|
|---|
| 4500 | <!--l. 479--><p class="noindent" >
|
|---|
| 4501 | <h5 class="subsubsectionHead"><span class="titlemark">4.3.5. </span> <a
|
|---|
| 4502 | id="x1-770004.3.5"></a>inverse coupling</h5>
|
|---|
| 4503 | <!--l. 481--><p class="noindent" >for each <span
|
|---|
| 4504 | class="cmtt-12">[i] </span>from <span
|
|---|
| 4505 | class="cmtt-12">[vorbis</span><span
|
|---|
| 4506 | class="cmtt-12">_mapping</span><span
|
|---|
| 4507 | class="cmtt-12">_coupling</span><span
|
|---|
| 4508 | class="cmtt-12">_steps]</span>-1 descending to 0
|
|---|
| 4509 | <!--l. 484--><p class="noindent" >
|
|---|
| 4510 | <dl class="enumerate-enumitem"><dt class="enumerate-enumitem">
|
|---|
| 4511 | 1. </dt><dd
|
|---|
| 4512 | class="enumerate-enumitem"><span
|
|---|
| 4513 | class="cmtt-12">[magnitude</span><span
|
|---|
| 4514 | class="cmtt-12">_vector] </span>= the residue vector for channel (vector
|
|---|
| 4515 | <span
|
|---|
| 4516 | class="cmtt-12">[vorbis</span><span
|
|---|
| 4517 | class="cmtt-12">_mapping</span><span
|
|---|
| 4518 | class="cmtt-12">_magnitude] </span>element <span
|
|---|
| 4519 | class="cmtt-12">[i]</span>)
|
|---|
| 4520 | </dd><dt class="enumerate-enumitem">
|
|---|
| 4521 | 2. </dt><dd
|
|---|
| 4522 | class="enumerate-enumitem"><span
|
|---|
| 4523 | class="cmtt-12">[angle</span><span
|
|---|
| 4524 | class="cmtt-12">_vector] </span>= the residue vector for channel (vector <span
|
|---|
| 4525 | class="cmtt-12">[vorbis</span><span
|
|---|
| 4526 | class="cmtt-12">_mapping</span><span
|
|---|
| 4527 | class="cmtt-12">_angle]</span>
|
|---|
| 4528 | element <span
|
|---|
| 4529 | class="cmtt-12">[i]</span>)
|
|---|
| 4530 | </dd><dt class="enumerate-enumitem">
|
|---|
| 4531 | 3. </dt><dd
|
|---|
| 4532 | class="enumerate-enumitem">for each scalar value <span
|
|---|
| 4533 | class="cmtt-12">[M] </span>in vector <span
|
|---|
| 4534 | class="cmtt-12">[magnitude</span><span
|
|---|
| 4535 | class="cmtt-12">_vector] </span>and the corresponding scalar value
|
|---|
| 4536 | <span
|
|---|
| 4537 | class="cmtt-12">[A] </span>in vector <span
|
|---|
| 4538 | class="cmtt-12">[angle</span><span
|
|---|
| 4539 | class="cmtt-12">_vector]</span>:
|
|---|
| 4540 | <dl class="enumerate-enumitem"><dt class="enumerate-enumitem">
|
|---|
| 4541 | a) </dt><dd
|
|---|
| 4542 | class="enumerate-enumitem">if (<span
|
|---|
| 4543 | class="cmtt-12">[M] </span>is greater than zero)
|
|---|
| 4544 |
|
|---|
| 4545 |
|
|---|
| 4546 |
|
|---|
| 4547 | <dl class="enumerate-enumitem"><dt class="enumerate-enumitem">
|
|---|
| 4548 | i. </dt><dd
|
|---|
| 4549 | class="enumerate-enumitem">if (<span
|
|---|
| 4550 | class="cmtt-12">[A] </span>is greater than zero)
|
|---|
| 4551 | <dl class="enumerate-enumitem"><dt class="enumerate-enumitem">
|
|---|
| 4552 | A. </dt><dd
|
|---|
| 4553 | class="enumerate-enumitem"><span
|
|---|
| 4554 | class="cmtt-12">[new</span><span
|
|---|
| 4555 | class="cmtt-12">_M] </span>= <span
|
|---|
| 4556 | class="cmtt-12">[M]</span>
|
|---|
| 4557 | </dd><dt class="enumerate-enumitem">
|
|---|
| 4558 | B. </dt><dd
|
|---|
| 4559 | class="enumerate-enumitem"><span
|
|---|
| 4560 | class="cmtt-12">[new</span><span
|
|---|
| 4561 | class="cmtt-12">_A] </span>= <span
|
|---|
| 4562 | class="cmtt-12">[M]</span>-<span
|
|---|
| 4563 | class="cmtt-12">[A]</span></dd></dl>
|
|---|
| 4564 | <!--l. 497--><p class="noindent" >else
|
|---|
| 4565 | <dl class="enumerate-enumitem"><dt class="enumerate-enumitem">
|
|---|
| 4566 | A. </dt><dd
|
|---|
| 4567 | class="enumerate-enumitem"><span
|
|---|
| 4568 | class="cmtt-12">[new</span><span
|
|---|
| 4569 | class="cmtt-12">_A] </span>= <span
|
|---|
| 4570 | class="cmtt-12">[M]</span>
|
|---|
| 4571 | </dd><dt class="enumerate-enumitem">
|
|---|
| 4572 | B. </dt><dd
|
|---|
| 4573 | class="enumerate-enumitem"><span
|
|---|
| 4574 | class="cmtt-12">[new</span><span
|
|---|
| 4575 | class="cmtt-12">_M] </span>= <span
|
|---|
| 4576 | class="cmtt-12">[M]</span>+<span
|
|---|
| 4577 | class="cmtt-12">[A]</span></dd></dl>
|
|---|
| 4578 | </dd></dl>
|
|---|
| 4579 | <!--l. 504--><p class="noindent" >else
|
|---|
| 4580 | <dl class="enumerate-enumitem"><dt class="enumerate-enumitem">
|
|---|
| 4581 | i. </dt><dd
|
|---|
| 4582 | class="enumerate-enumitem">if (<span
|
|---|
| 4583 | class="cmtt-12">[A] </span>is greater than zero)
|
|---|
| 4584 | <dl class="enumerate-enumitem"><dt class="enumerate-enumitem">
|
|---|
| 4585 | A. </dt><dd
|
|---|
| 4586 | class="enumerate-enumitem"><span
|
|---|
| 4587 | class="cmtt-12">[new</span><span
|
|---|
| 4588 | class="cmtt-12">_M] </span>= <span
|
|---|
| 4589 | class="cmtt-12">[M]</span>
|
|---|
| 4590 | </dd><dt class="enumerate-enumitem">
|
|---|
| 4591 | B. </dt><dd
|
|---|
| 4592 | class="enumerate-enumitem"><span
|
|---|
| 4593 | class="cmtt-12">[new</span><span
|
|---|
| 4594 | class="cmtt-12">_A] </span>= <span
|
|---|
| 4595 | class="cmtt-12">[M]</span>+<span
|
|---|
| 4596 | class="cmtt-12">[A]</span></dd></dl>
|
|---|
| 4597 | <!--l. 511--><p class="noindent" >else
|
|---|
| 4598 | <dl class="enumerate-enumitem"><dt class="enumerate-enumitem">
|
|---|
| 4599 | A. </dt><dd
|
|---|
| 4600 | class="enumerate-enumitem"><span
|
|---|
| 4601 | class="cmtt-12">[new</span><span
|
|---|
| 4602 | class="cmtt-12">_A] </span>= <span
|
|---|
| 4603 | class="cmtt-12">[M]</span>
|
|---|
| 4604 | </dd><dt class="enumerate-enumitem">
|
|---|
| 4605 | B. </dt><dd
|
|---|
| 4606 | class="enumerate-enumitem"><span
|
|---|
| 4607 | class="cmtt-12">[new</span><span
|
|---|
| 4608 | class="cmtt-12">_M] </span>= <span
|
|---|
| 4609 | class="cmtt-12">[M]</span>-<span
|
|---|
| 4610 | class="cmtt-12">[A]</span></dd></dl>
|
|---|
| 4611 | </dd></dl>
|
|---|
| 4612 | </dd><dt class="enumerate-enumitem">
|
|---|
| 4613 | b) </dt><dd
|
|---|
| 4614 | class="enumerate-enumitem">set scalar value <span
|
|---|
| 4615 | class="cmtt-12">[M] </span>in vector <span
|
|---|
| 4616 | class="cmtt-12">[magnitude</span><span
|
|---|
| 4617 | class="cmtt-12">_vector] </span>to <span
|
|---|
| 4618 | class="cmtt-12">[new</span><span
|
|---|
| 4619 | class="cmtt-12">_M]</span>
|
|---|
| 4620 | </dd><dt class="enumerate-enumitem">
|
|---|
| 4621 | c) </dt><dd
|
|---|
| 4622 | class="enumerate-enumitem">set scalar value <span
|
|---|
| 4623 | class="cmtt-12">[A] </span>in vector <span
|
|---|
| 4624 | class="cmtt-12">[angle</span><span
|
|---|
| 4625 | class="cmtt-12">_vector] </span>to <span
|
|---|
| 4626 | class="cmtt-12">[new</span><span
|
|---|
| 4627 | class="cmtt-12">_A]</span></dd></dl>
|
|---|
| 4628 | </dd></dl>
|
|---|
| 4629 |
|
|---|
| 4630 |
|
|---|
| 4631 |
|
|---|
| 4632 | <!--l. 528--><p class="noindent" >
|
|---|
| 4633 | <h5 class="subsubsectionHead"><span class="titlemark">4.3.6. </span> <a
|
|---|
| 4634 | id="x1-780004.3.6"></a>dot product</h5>
|
|---|
| 4635 | <!--l. 530--><p class="noindent" >For each channel, synthesize the floor curve from the decoded floor information, according to
|
|---|
| 4636 | packet type. Note that the vector synthesis length for floor computation is <span
|
|---|
| 4637 | class="cmtt-12">[n]</span>/2.
|
|---|
| 4638 | <!--l. 534--><p class="noindent" >For each channel, multiply each element of the floor curve by each element of that
|
|---|
| 4639 | channel’s residue vector. The result is the dot product of the floor and residue vectors for
|
|---|
| 4640 | each channel; the produced vectors are the length <span
|
|---|
| 4641 | class="cmtt-12">[n]</span>/2 audio spectrum for each
|
|---|
| 4642 | channel.
|
|---|
| 4643 | <!--l. 542--><p class="noindent" >One point is worth mentioning about this dot product; a common mistake in a fixed point
|
|---|
| 4644 | implementation might be to assume that a 32 bit fixed-point representation for floor and
|
|---|
| 4645 | residue and direct multiplication of the vectors is sufficient for acceptable spectral depth
|
|---|
| 4646 | in all cases because it happens to mostly work with the current Xiph.Org reference
|
|---|
| 4647 | encoder.
|
|---|
| 4648 | <!--l. 549--><p class="noindent" >However, floor vector values can span <span
|
|---|
| 4649 | class="cmsy-10x-x-120">~</span>140dB (<span
|
|---|
| 4650 | class="cmsy-10x-x-120">~</span>24 bits unsigned), and the audio spectrum
|
|---|
| 4651 | vector should represent a minimum of 120dB (<span
|
|---|
| 4652 | class="cmsy-10x-x-120">~</span>21 bits with sign), even when output is to a 16
|
|---|
| 4653 | bit PCM device. For the residue vector to represent full scale if the floor is nailed
|
|---|
| 4654 | to <span
|
|---|
| 4655 | class="cmsy-10x-x-120">-</span>140dB, it must be able to span 0 to +140dB. For the residue vector to reach
|
|---|
| 4656 | full scale if the floor is nailed at 0dB, it must be able to represent <span
|
|---|
| 4657 | class="cmsy-10x-x-120">-</span>140dB to +0dB.
|
|---|
| 4658 | Thus, in order to handle full range dynamics, a residue vector may span <span
|
|---|
| 4659 | class="cmsy-10x-x-120">-</span>140dB to
|
|---|
| 4660 | +140dB entirely within spec. A 280dB range is approximately 48 bits with sign; thus the
|
|---|
| 4661 | residue vector must be able to represent a 48 bit range and the dot product must
|
|---|
| 4662 | be able to handle an effective 48 bit times 24 bit multiplication. This range may be
|
|---|
| 4663 | achieved using large (64 bit or larger) integers, or implementing a movable binary point
|
|---|
| 4664 | representation.
|
|---|
| 4665 | <!--l. 566--><p class="noindent" >
|
|---|
| 4666 | <h5 class="subsubsectionHead"><span class="titlemark">4.3.7. </span> <a
|
|---|
| 4667 | id="x1-790004.3.7"></a>inverse MDCT</h5>
|
|---|
| 4668 | <!--l. 568--><p class="noindent" >Convert the audio spectrum vector of each channel back into time domain PCM audio via an
|
|---|
| 4669 | inverse Modified Discrete Cosine Transform (MDCT). A detailed description of the MDCT is
|
|---|
| 4670 | available in <span class="cite">[<a
|
|---|
| 4671 | href="#XSporer/Brandenburg/Edler">1</a>]</span>. The window function used for the MDCT is the function described
|
|---|
| 4672 | earlier.
|
|---|
| 4673 |
|
|---|
| 4674 |
|
|---|
| 4675 |
|
|---|
| 4676 | <!--l. 575--><p class="noindent" >
|
|---|
| 4677 | <h5 class="subsubsectionHead"><span class="titlemark">4.3.8. </span> <a
|
|---|
| 4678 | id="x1-800004.3.8"></a>overlap_add</h5>
|
|---|
| 4679 | <!--l. 577--><p class="noindent" >Windowed MDCT output is overlapped and added with the right hand data of the previous
|
|---|
| 4680 | window such that the 3/4 point of the previous window is aligned with the 1/4 point of the
|
|---|
| 4681 | current window (as illustrated in <a
|
|---|
| 4682 | href="#x1-260001.3.2">paragraph 1.3.2</a>, “<a
|
|---|
| 4683 | href="#x1-260001.3.2">Window shape decode (long windows
|
|---|
| 4684 | only)<!--tex4ht:ref: vorbis:spec:window --></a>”). The overlapped portion produced from overlapping the previous and current frame data
|
|---|
| 4685 | is finished data to be returned by the decoder. This data spans from the center of
|
|---|
| 4686 | the previous window to the center of the current window. In the case of same-sized
|
|---|
| 4687 | windows, the amount of data to return is one-half block consisting of and only of the
|
|---|
| 4688 | overlapped portions. When overlapping a short and long window, much of the returned
|
|---|
| 4689 | range does not actually overlap. This does not damage transform orthogonality. Pay
|
|---|
| 4690 | attention however to returning the correct data range; the amount of data to be returned
|
|---|
| 4691 | is:
|
|---|
| 4692 | <!--l. 591--><p class="noindent" >
|
|---|
| 4693 | <div class="fancyvrb" id="fancyvrb22"><a
|
|---|
| 4694 | id="x1-80002r1"></a><span
|
|---|
| 4695 | class="cmr-6">1</span><span
|
|---|
| 4696 | class="cmtt-8">window_blocksize(previous_window)/4+window_blocksize(current_window)/4</span></div>
|
|---|
| 4697 | <!--l. 595--><p class="noindent" >from the center (element windowsize/2) of the previous window to the center (element
|
|---|
| 4698 | windowsize/2-1, inclusive) of the current window.
|
|---|
| 4699 | <!--l. 598--><p class="noindent" >Data is not returned from the first frame; it must be used to ’prime’ the decode engine. The
|
|---|
| 4700 | encoder accounts for this priming when calculating PCM offsets; after the first frame, the proper
|
|---|
| 4701 | PCM output offset is ’0’ (as no data has been returned yet).
|
|---|
| 4702 | <!--l. 605--><p class="noindent" >
|
|---|
| 4703 | <h5 class="subsubsectionHead"><span class="titlemark">4.3.9. </span> <a
|
|---|
| 4704 | id="x1-810004.3.9"></a>output channel order</h5>
|
|---|
| 4705 | <!--l. 607--><p class="noindent" >Vorbis I specifies only a channel mapping type 0. In mapping type 0, channel mapping is
|
|---|
| 4706 | implicitly defined as follows for standard audio applications. As of revision 16781 (20100113), the
|
|---|
| 4707 | specification adds defined channel locations for 6.1 and 7.1 surround. Ordering/location for
|
|---|
| 4708 | greater-than-eight channels remains ’left to the implementation’.
|
|---|
| 4709 | <!--l. 613--><p class="noindent" >These channel orderings refer to order within the encoded stream. It is naturally possible for a
|
|---|
| 4710 | decoder to produce output with channels in any order. Any such decoder should explicitly
|
|---|
| 4711 | document channel reordering behavior.
|
|---|
| 4712 | <!--l. 619--><p class="noindent" >
|
|---|
| 4713 | <dl class="description"><dt class="description">
|
|---|
| 4714 | <span
|
|---|
| 4715 | class="cmssbx-10x-x-120">one channel</span> </dt><dd
|
|---|
| 4716 | class="description">the stream is monophonic
|
|---|
| 4717 |
|
|---|
| 4718 |
|
|---|
| 4719 |
|
|---|
| 4720 | </dd><dt class="description">
|
|---|
| 4721 | <span
|
|---|
| 4722 | class="cmssbx-10x-x-120">two channels</span> </dt><dd
|
|---|
| 4723 | class="description">the stream is stereo. channel order: left, right
|
|---|
| 4724 | </dd><dt class="description">
|
|---|
| 4725 | <span
|
|---|
| 4726 | class="cmssbx-10x-x-120">three channels</span> </dt><dd
|
|---|
| 4727 | class="description">the stream is a 1d-surround encoding. channel order: left, center, right
|
|---|
| 4728 | </dd><dt class="description">
|
|---|
| 4729 | <span
|
|---|
| 4730 | class="cmssbx-10x-x-120">four channels</span> </dt><dd
|
|---|
| 4731 | class="description">the stream is quadraphonic surround. channel order: front left, front right,
|
|---|
| 4732 | rear left, rear right
|
|---|
| 4733 | </dd><dt class="description">
|
|---|
| 4734 | <span
|
|---|
| 4735 | class="cmssbx-10x-x-120">five channels</span> </dt><dd
|
|---|
| 4736 | class="description">the stream is five-channel surround. channel order: front left, center, front
|
|---|
| 4737 | right, rear left, rear right
|
|---|
| 4738 | </dd><dt class="description">
|
|---|
| 4739 | <span
|
|---|
| 4740 | class="cmssbx-10x-x-120">six channels</span> </dt><dd
|
|---|
| 4741 | class="description">the stream is 5.1 surround. channel order: front left, center, front right, rear
|
|---|
| 4742 | left, rear right, LFE
|
|---|
| 4743 | </dd><dt class="description">
|
|---|
| 4744 | <span
|
|---|
| 4745 | class="cmssbx-10x-x-120">seven channels</span> </dt><dd
|
|---|
| 4746 | class="description">the stream is 6.1 surround. channel order: front left, center, front right,
|
|---|
| 4747 | side left, side right, rear center, LFE
|
|---|
| 4748 | </dd><dt class="description">
|
|---|
| 4749 | <span
|
|---|
| 4750 | class="cmssbx-10x-x-120">eight channels</span> </dt><dd
|
|---|
| 4751 | class="description">the stream is 7.1 surround. channel order: front left, center, front right,
|
|---|
| 4752 | side left, side right, rear left, rear right, LFE
|
|---|
| 4753 | </dd><dt class="description">
|
|---|
| 4754 | <span
|
|---|
| 4755 | class="cmssbx-10x-x-120">greater than eight channels</span> </dt><dd
|
|---|
| 4756 | class="description">channel use and order is defined by the application
|
|---|
| 4757 | </dd></dl>
|
|---|
| 4758 | <!--l. 655--><p class="noindent" >Applications using Vorbis for dedicated purposes may define channel mapping as seen fit. Future
|
|---|
| 4759 | channel mappings (such as three and four channel <a
|
|---|
| 4760 | href="http://www.ambisonic.net/" >Ambisonics</a>) will make use of channel
|
|---|
| 4761 | mappings other than mapping 0.
|
|---|
| 4762 |
|
|---|
| 4763 |
|
|---|
| 4764 |
|
|---|
| 4765 |
|
|---|
| 4766 |
|
|---|
| 4767 |
|
|---|
| 4768 | <h3 class="sectionHead"><span class="titlemark">5. </span> <a
|
|---|
| 4769 | id="x1-820005"></a>comment field and header specification</h3>
|
|---|
| 4770 | <!--l. 5--><p class="noindent" >
|
|---|
| 4771 | <h4 class="subsectionHead"><span class="titlemark">5.1. </span> <a
|
|---|
| 4772 | id="x1-830005.1"></a>Overview</h4>
|
|---|
| 4773 | <!--l. 7--><p class="noindent" >The Vorbis text comment header is the second (of three) header packets that begin a Vorbis
|
|---|
| 4774 | bitstream. It is meant for short text comments, not arbitrary metadata; arbitrary metadata
|
|---|
| 4775 | belongs in a separate logical bitstream (usually an XML stream type) that provides greater
|
|---|
| 4776 | structure and machine parseability.
|
|---|
| 4777 | <!--l. 13--><p class="noindent" >The comment field is meant to be used much like someone jotting a quick note on the bottom of
|
|---|
| 4778 | a CDR. It should be a little information to remember the disc by and explain it to others; a
|
|---|
| 4779 | short, to-the-point text note that need not only be a couple words, but isn’t going to be more
|
|---|
| 4780 | than a short paragraph. The essentials, in other words, whatever they turn out to be,
|
|---|
| 4781 | eg:
|
|---|
| 4782 | <!--l. 20--><p class="noindent" >
|
|---|
| 4783 | <div class="quote">
|
|---|
| 4784 | <!--l. 21--><p class="noindent" >Honest Bob and the Factory-to-Dealer-Incentives, <span
|
|---|
| 4785 | class="cmti-12">“I’m Still Around”</span>, opening
|
|---|
| 4786 | for Moxy Früvous, 1997.</div>
|
|---|
| 4787 | <!--l. 28--><p class="noindent" >
|
|---|
| 4788 | <h4 class="subsectionHead"><span class="titlemark">5.2. </span> <a
|
|---|
| 4789 | id="x1-840005.2"></a>Comment encoding</h4>
|
|---|
| 4790 | <!--l. 30--><p class="noindent" >
|
|---|
| 4791 | <h5 class="subsubsectionHead"><span class="titlemark">5.2.1. </span> <a
|
|---|
| 4792 | id="x1-850005.2.1"></a>Structure</h5>
|
|---|
| 4793 | <!--l. 32--><p class="noindent" >The comment header is logically a list of eight-bit-clean vectors; the number of vectors is
|
|---|
| 4794 | bounded to 2<sup><span
|
|---|
| 4795 | class="cmr-8">32</span></sup> <span
|
|---|
| 4796 | class="cmsy-10x-x-120">- </span>1 and the length of each vector is limited to 2<sup><span
|
|---|
| 4797 | class="cmr-8">32</span></sup> <span
|
|---|
| 4798 | class="cmsy-10x-x-120">- </span>1 bytes. The vector length is
|
|---|
| 4799 |
|
|---|
| 4800 |
|
|---|
| 4801 |
|
|---|
| 4802 | encoded; the vector contents themselves are not null terminated. In addition to the vector list,
|
|---|
| 4803 | there is a single vector for vendor name (also 8 bit clean, length encoded in 32 bits). For
|
|---|
| 4804 | example, the 1.0 release of libvorbis set the vendor string to “Xiph.Org libVorbis I
|
|---|
| 4805 | 20020717”.
|
|---|
| 4806 | <!--l. 40--><p class="noindent" >The vector lengths and number of vectors are stored lsb first, according to the bit
|
|---|
| 4807 | packing conventions of the vorbis codec. However, since data in the comment header
|
|---|
| 4808 | is octet-aligned, they can simply be read as unaligned 32 bit little endian unsigned
|
|---|
| 4809 | integers.
|
|---|
| 4810 | <!--l. 45--><p class="noindent" >The comment header is decoded as follows:
|
|---|
| 4811 | <!--l. 47--><p class="noindent" >
|
|---|
| 4812 | <div class="fancyvrb" id="fancyvrb23"><a
|
|---|
| 4813 | id="x1-85002r1"></a><span
|
|---|
| 4814 | class="cmr-6">1</span><span
|
|---|
| 4815 | class="cmtt-8"> </span><span
|
|---|
| 4816 | class="cmtt-8"> 1)</span><span
|
|---|
| 4817 | class="cmtt-8"> [vendor\_length]</span><span
|
|---|
| 4818 | class="cmtt-8"> =</span><span
|
|---|
| 4819 | class="cmtt-8"> read</span><span
|
|---|
| 4820 | class="cmtt-8"> an</span><span
|
|---|
| 4821 | class="cmtt-8"> unsigned</span><span
|
|---|
| 4822 | class="cmtt-8"> integer</span><span
|
|---|
| 4823 | class="cmtt-8"> of</span><span
|
|---|
| 4824 | class="cmtt-8"> 32</span><span
|
|---|
| 4825 | class="cmtt-8"> bits</span><br class="fancyvrb" /><a
|
|---|
| 4826 | id="x1-85004r2"></a><span
|
|---|
| 4827 | class="cmr-6">2</span><span
|
|---|
| 4828 | class="cmtt-8"> </span><span
|
|---|
| 4829 | class="cmtt-8"> 2)</span><span
|
|---|
| 4830 | class="cmtt-8"> [vendor\_string]</span><span
|
|---|
| 4831 | class="cmtt-8"> =</span><span
|
|---|
| 4832 | class="cmtt-8"> read</span><span
|
|---|
| 4833 | class="cmtt-8"> a</span><span
|
|---|
| 4834 | class="cmtt-8"> UTF-8</span><span
|
|---|
| 4835 | class="cmtt-8"> vector</span><span
|
|---|
| 4836 | class="cmtt-8"> as</span><span
|
|---|
| 4837 | class="cmtt-8"> [vendor\_length]</span><span
|
|---|
| 4838 | class="cmtt-8"> octets</span>
|
|---|
| 4839 | <br class="fancyvrb" /><a
|
|---|
| 4840 | id="x1-85006r3"></a><span
|
|---|
| 4841 | class="cmr-6">3</span><span
|
|---|
| 4842 | class="cmtt-8"> </span><span
|
|---|
| 4843 | class="cmtt-8"> 3)</span><span
|
|---|
| 4844 | class="cmtt-8"> [user\_comment\_list\_length]</span><span
|
|---|
| 4845 | class="cmtt-8"> =</span><span
|
|---|
| 4846 | class="cmtt-8"> read</span><span
|
|---|
| 4847 | class="cmtt-8"> an</span><span
|
|---|
| 4848 | class="cmtt-8"> unsigned</span><span
|
|---|
| 4849 | class="cmtt-8"> integer</span><span
|
|---|
| 4850 | class="cmtt-8"> of</span><span
|
|---|
| 4851 | class="cmtt-8"> 32</span><span
|
|---|
| 4852 | class="cmtt-8"> bits</span><br class="fancyvrb" /><a
|
|---|
| 4853 | id="x1-85008r4"></a><span
|
|---|
| 4854 | class="cmr-6">4</span><span
|
|---|
| 4855 | class="cmtt-8"> </span><span
|
|---|
| 4856 | class="cmtt-8"> 4)</span><span
|
|---|
| 4857 | class="cmtt-8"> iterate</span><span
|
|---|
| 4858 | class="cmtt-8"> [user\_comment\_list\_length]</span><span
|
|---|
| 4859 | class="cmtt-8"> times</span><span
|
|---|
| 4860 | class="cmtt-8"> {</span>
|
|---|
| 4861 | <br class="fancyvrb" /><a
|
|---|
| 4862 | id="x1-85010r5"></a><span
|
|---|
| 4863 | class="cmr-6">5</span><span
|
|---|
| 4864 | class="cmtt-8"> </span><span
|
|---|
| 4865 | class="cmtt-8"> </span><span
|
|---|
| 4866 | class="cmtt-8"> </span><span
|
|---|
| 4867 | class="cmtt-8"> </span><span
|
|---|
| 4868 | class="cmtt-8"> </span><span
|
|---|
| 4869 | class="cmtt-8"> </span><span
|
|---|
| 4870 | class="cmtt-8"> 5)</span><span
|
|---|
| 4871 | class="cmtt-8"> [length]</span><span
|
|---|
| 4872 | class="cmtt-8"> =</span><span
|
|---|
| 4873 | class="cmtt-8"> read</span><span
|
|---|
| 4874 | class="cmtt-8"> an</span><span
|
|---|
| 4875 | class="cmtt-8"> unsigned</span><span
|
|---|
| 4876 | class="cmtt-8"> integer</span><span
|
|---|
| 4877 | class="cmtt-8"> of</span><span
|
|---|
| 4878 | class="cmtt-8"> 32</span><span
|
|---|
| 4879 | class="cmtt-8"> bits</span><br class="fancyvrb" /><a
|
|---|
| 4880 | id="x1-85012r6"></a><span
|
|---|
| 4881 | class="cmr-6">6</span><span
|
|---|
| 4882 | class="cmtt-8"> </span><span
|
|---|
| 4883 | class="cmtt-8"> </span><span
|
|---|
| 4884 | class="cmtt-8"> </span><span
|
|---|
| 4885 | class="cmtt-8"> </span><span
|
|---|
| 4886 | class="cmtt-8"> </span><span
|
|---|
| 4887 | class="cmtt-8"> </span><span
|
|---|
| 4888 | class="cmtt-8"> 6)</span><span
|
|---|
| 4889 | class="cmtt-8"> this</span><span
|
|---|
| 4890 | class="cmtt-8"> iteration’s</span><span
|
|---|
| 4891 | class="cmtt-8"> user</span><span
|
|---|
| 4892 | class="cmtt-8"> comment</span><span
|
|---|
| 4893 | class="cmtt-8"> =</span><span
|
|---|
| 4894 | class="cmtt-8"> read</span><span
|
|---|
| 4895 | class="cmtt-8"> a</span><span
|
|---|
| 4896 | class="cmtt-8"> UTF-8</span><span
|
|---|
| 4897 | class="cmtt-8"> vector</span><span
|
|---|
| 4898 | class="cmtt-8"> as</span><span
|
|---|
| 4899 | class="cmtt-8"> [length]</span><span
|
|---|
| 4900 | class="cmtt-8"> octets</span>
|
|---|
| 4901 | <br class="fancyvrb" /><a
|
|---|
| 4902 | id="x1-85014r7"></a><span
|
|---|
| 4903 | class="cmr-6">7</span><span
|
|---|
| 4904 | class="cmtt-8"> </span><span
|
|---|
| 4905 | class="cmtt-8"> </span><span
|
|---|
| 4906 | class="cmtt-8"> </span><span
|
|---|
| 4907 | class="cmtt-8"> </span><span
|
|---|
| 4908 | class="cmtt-8"> }</span><br class="fancyvrb" /><a
|
|---|
| 4909 | id="x1-85016r8"></a><span
|
|---|
| 4910 | class="cmr-6">8</span><span
|
|---|
| 4911 | class="cmtt-8"> </span><span
|
|---|
| 4912 | class="cmtt-8"> 7)</span><span
|
|---|
| 4913 | class="cmtt-8"> [framing\_bit]</span><span
|
|---|
| 4914 | class="cmtt-8"> =</span><span
|
|---|
| 4915 | class="cmtt-8"> read</span><span
|
|---|
| 4916 | class="cmtt-8"> a</span><span
|
|---|
| 4917 | class="cmtt-8"> single</span><span
|
|---|
| 4918 | class="cmtt-8"> bit</span><span
|
|---|
| 4919 | class="cmtt-8"> as</span><span
|
|---|
| 4920 | class="cmtt-8"> boolean</span><br class="fancyvrb" /><a
|
|---|
| 4921 | id="x1-85018r9"></a><span
|
|---|
| 4922 | class="cmr-6">9</span><span
|
|---|
| 4923 | class="cmtt-8"> </span><span
|
|---|
| 4924 | class="cmtt-8"> 8)</span><span
|
|---|
| 4925 | class="cmtt-8"> if</span><span
|
|---|
| 4926 | class="cmtt-8"> (</span><span
|
|---|
| 4927 | class="cmtt-8"> [framing\_bit]</span><span
|
|---|
| 4928 | class="cmtt-8"> unset</span><span
|
|---|
| 4929 | class="cmtt-8"> or</span><span
|
|---|
| 4930 | class="cmtt-8"> end-of-packet</span><span
|
|---|
| 4931 | class="cmtt-8"> )</span><span
|
|---|
| 4932 | class="cmtt-8"> then</span><span
|
|---|
| 4933 | class="cmtt-8"> ERROR</span><br class="fancyvrb" /><a
|
|---|
| 4934 | id="x1-85020r10"></a><span
|
|---|
| 4935 | class="cmr-6">10</span><span
|
|---|
| 4936 | class="cmtt-8"> </span><span
|
|---|
| 4937 | class="cmtt-8"> 9)</span><span
|
|---|
| 4938 | class="cmtt-8"> done.</span></div>
|
|---|
| 4939 | <!--l. 63--><p class="noindent" >
|
|---|
| 4940 | <h5 class="subsubsectionHead"><span class="titlemark">5.2.2. </span> <a
|
|---|
| 4941 | id="x1-860005.2.2"></a>Content vector format</h5>
|
|---|
| 4942 | <!--l. 65--><p class="noindent" >The comment vectors are structured similarly to a UNIX environment variable. That is,
|
|---|
| 4943 | comment fields consist of a field name and a corresponding value and look like:
|
|---|
| 4944 | <!--l. 69--><p class="noindent" >
|
|---|
| 4945 | <div class="quote">
|
|---|
| 4946 | <!--l. 70--><p class="noindent" >
|
|---|
| 4947 | <div class="fancyvrb" id="fancyvrb24"><a
|
|---|
| 4948 | id="x1-86002r1"></a><span
|
|---|
| 4949 | class="cmr-6">1</span><span
|
|---|
| 4950 | class="cmtt-8">comment[0]="ARTIST=me";</span><br class="fancyvrb" /><a
|
|---|
| 4951 | id="x1-86004r2"></a><span
|
|---|
| 4952 | class="cmr-6">2</span><span
|
|---|
| 4953 | class="cmtt-8">comment[1]="TITLE=the</span><span
|
|---|
| 4954 | class="cmtt-8"> sound</span><span
|
|---|
| 4955 | class="cmtt-8"> of</span><span
|
|---|
| 4956 | class="cmtt-8"> Vorbis";</span></div>
|
|---|
| 4957 | </div>
|
|---|
| 4958 | <!--l. 76--><p class="noindent" >The field name is case-insensitive and may consist of ASCII 0x20 through 0x7D, 0x3D (’=’)
|
|---|
| 4959 | excluded. ASCII 0x41 through 0x5A inclusive (characters A-Z) is to be considered equivalent to
|
|---|
| 4960 | ASCII 0x61 through 0x7A inclusive (characters a-z).
|
|---|
| 4961 | <!--l. 82--><p class="noindent" >The field name is immediately followed by ASCII 0x3D (’=’); this equals sign is used to
|
|---|
| 4962 | terminate the field name.
|
|---|
| 4963 | <!--l. 86--><p class="noindent" >0x3D is followed by 8 bit clean UTF-8 encoded value of the field contents to the end of the
|
|---|
| 4964 | field.
|
|---|
| 4965 |
|
|---|
| 4966 |
|
|---|
| 4967 |
|
|---|
| 4968 | <!--l. 90--><p class="noindent" ><span class="paragraphHead"><a
|
|---|
| 4969 | id="x1-870005.2.2"></a><span
|
|---|
| 4970 | class="cmbx-12">Field names</span></span>
|
|---|
| 4971 | Below is a proposed, minimal list of standard field names with a description of intended use. No
|
|---|
| 4972 | single or group of field names is mandatory; a comment header may contain one, all or none of
|
|---|
| 4973 | the names in this list.
|
|---|
| 4974 | <!--l. 98--><p class="noindent" >
|
|---|
| 4975 | <dl class="description"><dt class="description">
|
|---|
| 4976 | <span
|
|---|
| 4977 | class="cmssbx-10x-x-120">TITLE</span> </dt><dd
|
|---|
| 4978 | class="description">Track/Work name
|
|---|
| 4979 | </dd><dt class="description">
|
|---|
| 4980 | <span
|
|---|
| 4981 | class="cmssbx-10x-x-120">VERSION</span> </dt><dd
|
|---|
| 4982 | class="description">The version field may be used to differentiate multiple versions of the same
|
|---|
| 4983 | track title in a single collection. (e.g. remix info)
|
|---|
| 4984 | </dd><dt class="description">
|
|---|
| 4985 | <span
|
|---|
| 4986 | class="cmssbx-10x-x-120">ALBUM</span> </dt><dd
|
|---|
| 4987 | class="description">The collection name to which this track belongs
|
|---|
| 4988 | </dd><dt class="description">
|
|---|
| 4989 | <span
|
|---|
| 4990 | class="cmssbx-10x-x-120">TRACKNUMBER</span> </dt><dd
|
|---|
| 4991 | class="description">The track number of this piece if part of a specific larger collection or
|
|---|
| 4992 | album
|
|---|
| 4993 | </dd><dt class="description">
|
|---|
| 4994 | <span
|
|---|
| 4995 | class="cmssbx-10x-x-120">ARTIST</span> </dt><dd
|
|---|
| 4996 | class="description">The artist generally considered responsible for the work. In popular music this is
|
|---|
| 4997 | usually the performing band or singer. For classical music it would be the composer.
|
|---|
| 4998 | For an audio book it would be the author of the original text.
|
|---|
| 4999 | </dd><dt class="description">
|
|---|
| 5000 | <span
|
|---|
| 5001 | class="cmssbx-10x-x-120">PERFORMER</span> </dt><dd
|
|---|
| 5002 | class="description">The artist(s) who performed the work. In classical music this would be the
|
|---|
| 5003 | conductor, orchestra, soloists. In an audio book it would be the actor who did the
|
|---|
| 5004 | reading. In popular music this is typically the same as the ARTIST and is omitted.
|
|---|
| 5005 | </dd><dt class="description">
|
|---|
| 5006 | <span
|
|---|
| 5007 | class="cmssbx-10x-x-120">COPYRIGHT</span> </dt><dd
|
|---|
| 5008 | class="description">Copyright attribution, e.g., ’2001 Nobody’s Band’ or ’1999 Jack Moffitt’
|
|---|
| 5009 | </dd><dt class="description">
|
|---|
| 5010 | <span
|
|---|
| 5011 | class="cmssbx-10x-x-120">LICENSE</span> </dt><dd
|
|---|
| 5012 | class="description">License information, for example, ’All Rights Reserved’, ’Any Use
|
|---|
| 5013 | Permitted’, a URL to a license such as a Creative Commons license (e.g.
|
|---|
| 5014 | ”creativecommons.org/license/by/4.0/”) or similar.
|
|---|
| 5015 | </dd><dt class="description">
|
|---|
| 5016 | <span
|
|---|
| 5017 | class="cmssbx-10x-x-120">ORGANIZATION</span> </dt><dd
|
|---|
| 5018 | class="description">Name of the organization producing the track (i.e. the ’record label’)
|
|---|
| 5019 | </dd><dt class="description">
|
|---|
| 5020 | <span
|
|---|
| 5021 | class="cmssbx-10x-x-120">DESCRIPTION</span> </dt><dd
|
|---|
| 5022 | class="description">A short text description of the contents
|
|---|
| 5023 | </dd><dt class="description">
|
|---|
| 5024 | <span
|
|---|
| 5025 | class="cmssbx-10x-x-120">GENRE</span> </dt><dd
|
|---|
| 5026 | class="description">A short text indication of music genre
|
|---|
| 5027 |
|
|---|
| 5028 |
|
|---|
| 5029 |
|
|---|
| 5030 | </dd><dt class="description">
|
|---|
| 5031 | <span
|
|---|
| 5032 | class="cmssbx-10x-x-120">DATE</span> </dt><dd
|
|---|
| 5033 | class="description">Date the track was recorded
|
|---|
| 5034 | </dd><dt class="description">
|
|---|
| 5035 | <span
|
|---|
| 5036 | class="cmssbx-10x-x-120">LOCATION</span> </dt><dd
|
|---|
| 5037 | class="description">Location where track was recorded
|
|---|
| 5038 | </dd><dt class="description">
|
|---|
| 5039 | <span
|
|---|
| 5040 | class="cmssbx-10x-x-120">CONTACT</span> </dt><dd
|
|---|
| 5041 | class="description">Contact information for the creators or distributors of the track. This could
|
|---|
| 5042 | be a URL, an email address, the physical address of the producing label.
|
|---|
| 5043 | </dd><dt class="description">
|
|---|
| 5044 | <span
|
|---|
| 5045 | class="cmssbx-10x-x-120">ISRC</span> </dt><dd
|
|---|
| 5046 | class="description">International Standard Recording Code for the track; see <a
|
|---|
| 5047 | href="https://isrc.ifpi.org/" >the ISRC intro page</a> for
|
|---|
| 5048 | more information on ISRC numbers.
|
|---|
| 5049 | </dd></dl>
|
|---|
| 5050 | <!--l. 154--><p class="noindent" ><span class="paragraphHead"><a
|
|---|
| 5051 | id="x1-880005.2.2"></a><span
|
|---|
| 5052 | class="cmbx-12">Implications</span></span>
|
|---|
| 5053 | Field names should not be ’internationalized’; this is a concession to simplicity not
|
|---|
| 5054 | an attempt to exclude the majority of the world that doesn’t speak English. Field
|
|---|
| 5055 | <span
|
|---|
| 5056 | class="cmti-12">contents</span>, however, use the UTF-8 character encoding to allow easy representation of any
|
|---|
| 5057 | language.
|
|---|
| 5058 | <!--l. 162--><p class="noindent" >We have the length of the entirety of the field and restrictions on the field name so that
|
|---|
| 5059 | the field name is bounded in a known way. Thus we also have the length of the field
|
|---|
| 5060 | contents.
|
|---|
| 5061 | <!--l. 166--><p class="noindent" >Individual ’vendors’ may use non-standard field names within reason. The proper
|
|---|
| 5062 | use of comment fields should be clear through context at this point. Abuse will be
|
|---|
| 5063 | discouraged.
|
|---|
| 5064 | <!--l. 170--><p class="noindent" >There is no vendor-specific prefix to ’nonstandard’ field names. Vendors should make some effort
|
|---|
| 5065 | to avoid arbitrarily polluting the common namespace. We will generally collect the more useful
|
|---|
| 5066 | tags here to help with standardization.
|
|---|
| 5067 | <!--l. 175--><p class="noindent" >Field names are not required to be unique (occur once) within a comment header. As an
|
|---|
| 5068 | example, assume a track was recorded by three well know artists; the following is permissible,
|
|---|
| 5069 | and encouraged:
|
|---|
| 5070 | <!--l. 179--><p class="noindent" >
|
|---|
| 5071 | <div class="quote">
|
|---|
| 5072 | <!--l. 180--><p class="noindent" >
|
|---|
| 5073 | <div class="fancyvrb" id="fancyvrb25"><a
|
|---|
| 5074 | id="x1-88002r1"></a><span
|
|---|
| 5075 | class="cmr-6">1</span><span
|
|---|
| 5076 | class="cmtt-8">ARTIST=Dizzy</span><span
|
|---|
| 5077 | class="cmtt-8"> Gillespie</span><br class="fancyvrb" /><a
|
|---|
| 5078 | id="x1-88004r2"></a><span
|
|---|
| 5079 | class="cmr-6">2</span><span
|
|---|
| 5080 | class="cmtt-8">ARTIST=Sonny</span><span
|
|---|
| 5081 | class="cmtt-8"> Rollins</span><br class="fancyvrb" /><a
|
|---|
| 5082 | id="x1-88006r3"></a><span
|
|---|
| 5083 | class="cmr-6">3</span><span
|
|---|
| 5084 | class="cmtt-8">ARTIST=Sonny</span><span
|
|---|
| 5085 | class="cmtt-8"> Stitt</span></div>
|
|---|
| 5086 |
|
|---|
| 5087 |
|
|---|
| 5088 |
|
|---|
| 5089 | </div>
|
|---|
| 5090 | <!--l. 193--><p class="noindent" >
|
|---|
| 5091 | <h5 class="subsubsectionHead"><span class="titlemark">5.2.3. </span> <a
|
|---|
| 5092 | id="x1-890005.2.3"></a>Encoding</h5>
|
|---|
| 5093 | <!--l. 195--><p class="noindent" >The comment header comprises the entirety of the second bitstream header packet. Unlike the
|
|---|
| 5094 | first bitstream header packet, it is not generally the only packet on the second page and may not
|
|---|
| 5095 | be restricted to within the second bitstream page. The length of the comment header packet is
|
|---|
| 5096 | (practically) unbounded. The comment header packet is not optional; it must be present in the
|
|---|
| 5097 | bitstream even if it is effectively empty.
|
|---|
| 5098 | <!--l. 203--><p class="noindent" >The comment header is encoded as follows (as per Ogg’s standard bitstream mapping which
|
|---|
| 5099 | renders least-significant-bit of the word to be coded into the least significant available bit of the
|
|---|
| 5100 | current bitstream octet first):
|
|---|
| 5101 | <!--l. 209--><p class="noindent" >
|
|---|
| 5102 | <dl class="enumerate-enumitem"><dt class="enumerate-enumitem">
|
|---|
| 5103 | 1. </dt><dd
|
|---|
| 5104 | class="enumerate-enumitem">Vendor string length (32 bit unsigned quantity specifying number of octets)
|
|---|
| 5105 | </dd><dt class="enumerate-enumitem">
|
|---|
| 5106 | 2. </dt><dd
|
|---|
| 5107 | class="enumerate-enumitem">Vendor string ([vendor string length] octets coded from beginning of string to end of
|
|---|
| 5108 | string, not null terminated)
|
|---|
| 5109 | </dd><dt class="enumerate-enumitem">
|
|---|
| 5110 | 3. </dt><dd
|
|---|
| 5111 | class="enumerate-enumitem">Number of comment fields (32 bit unsigned quantity specifying number of fields)
|
|---|
| 5112 | </dd><dt class="enumerate-enumitem">
|
|---|
| 5113 | 4. </dt><dd
|
|---|
| 5114 | class="enumerate-enumitem">Comment field 0 length (if [Number of comment fields] <span
|
|---|
| 5115 | class="cmmi-12">> </span>0; 32 bit unsigned quantity
|
|---|
| 5116 | specifying number of octets)
|
|---|
| 5117 | </dd><dt class="enumerate-enumitem">
|
|---|
| 5118 | 5. </dt><dd
|
|---|
| 5119 | class="enumerate-enumitem">Comment field 0 ([Comment field 0 length] octets coded from beginning of string to
|
|---|
| 5120 | end of string, not null terminated)
|
|---|
| 5121 | </dd><dt class="enumerate-enumitem">
|
|---|
| 5122 | 6. </dt><dd
|
|---|
| 5123 | class="enumerate-enumitem">Comment field 1 length (if [Number of comment fields] <span
|
|---|
| 5124 | class="cmmi-12">> </span>1...)...
|
|---|
| 5125 | </dd></dl>
|
|---|
| 5126 | <!--l. 230--><p class="noindent" >This is actually somewhat easier to describe in code; implementation of the above can be found
|
|---|
| 5127 | in <span
|
|---|
| 5128 | class="cmtt-12">vorbis/lib/info.c</span>, <span
|
|---|
| 5129 | class="cmtt-12">_vorbis</span><span
|
|---|
| 5130 | class="cmtt-12">_pack</span><span
|
|---|
| 5131 | class="cmtt-12">_comment() </span>and <span
|
|---|
| 5132 | class="cmtt-12">_vorbis</span><span
|
|---|
| 5133 | class="cmtt-12">_unpack</span><span
|
|---|
| 5134 | class="cmtt-12">_comment()</span>.
|
|---|
| 5135 |
|
|---|
| 5136 |
|
|---|
| 5137 |
|
|---|
| 5138 |
|
|---|
| 5139 |
|
|---|
| 5140 |
|
|---|
| 5141 | <h3 class="sectionHead"><span class="titlemark">6. </span> <a
|
|---|
| 5142 | id="x1-900006"></a>Floor type 0 setup and decode</h3>
|
|---|
| 5143 | <!--l. 5--><p class="noindent" >
|
|---|
| 5144 | <h4 class="subsectionHead"><span class="titlemark">6.1. </span> <a
|
|---|
| 5145 | id="x1-910006.1"></a>Overview</h4>
|
|---|
| 5146 | <!--l. 7--><p class="noindent" >Vorbis floor type zero uses Line Spectral Pair (LSP, also alternately known as Line Spectral
|
|---|
| 5147 | Frequency or LSF) representation to encode a smooth spectral envelope curve as the frequency
|
|---|
| 5148 | response of the LSP filter. This representation is equivalent to a traditional all-pole infinite
|
|---|
| 5149 | impulse response filter as would be used in linear predictive coding; LSP representation may be
|
|---|
| 5150 | converted to LPC representation and vice-versa.
|
|---|
| 5151 | <!--l. 17--><p class="noindent" >
|
|---|
| 5152 | <h4 class="subsectionHead"><span class="titlemark">6.2. </span> <a
|
|---|
| 5153 | id="x1-920006.2"></a>Floor 0 format</h4>
|
|---|
| 5154 | <!--l. 19--><p class="noindent" >Floor zero configuration consists of six integer fields and a list of VQ codebooks for use in
|
|---|
| 5155 | coding/decoding the LSP filter coefficient values used by each frame.
|
|---|
| 5156 | <!--l. 23--><p class="noindent" >
|
|---|
| 5157 | <h5 class="subsubsectionHead"><span class="titlemark">6.2.1. </span> <a
|
|---|
| 5158 | id="x1-930006.2.1"></a>header decode</h5>
|
|---|
| 5159 | <!--l. 25--><p class="noindent" >Configuration information for instances of floor zero decodes from the codec setup header (third
|
|---|
| 5160 | packet). configuration decode proceeds as follows:
|
|---|
| 5161 | <!--l. 29--><p class="noindent" >
|
|---|
| 5162 | <div class="fancyvrb" id="fancyvrb26"><a
|
|---|
| 5163 | id="x1-93002r1"></a><span
|
|---|
| 5164 | class="cmr-6">1</span><span
|
|---|
| 5165 | class="cmtt-8"> </span><span
|
|---|
| 5166 | class="cmtt-8"> 1)</span><span
|
|---|
| 5167 | class="cmtt-8"> [floor0</span><span
|
|---|
| 5168 | class="cmtt-8">_order]</span><span
|
|---|
| 5169 | class="cmtt-8"> =</span><span
|
|---|
| 5170 | class="cmtt-8"> read</span><span
|
|---|
| 5171 | class="cmtt-8"> an</span><span
|
|---|
| 5172 | class="cmtt-8"> unsigned</span><span
|
|---|
| 5173 | class="cmtt-8"> integer</span><span
|
|---|
| 5174 | class="cmtt-8"> of</span><span
|
|---|
| 5175 | class="cmtt-8"> 8</span><span
|
|---|
| 5176 | class="cmtt-8"> bits</span><br class="fancyvrb" /><a
|
|---|
| 5177 | id="x1-93004r2"></a><span
|
|---|
| 5178 | class="cmr-6">2</span><span
|
|---|
| 5179 | class="cmtt-8"> </span><span
|
|---|
| 5180 | class="cmtt-8"> 2)</span><span
|
|---|
| 5181 | class="cmtt-8"> [floor0</span><span
|
|---|
| 5182 | class="cmtt-8">_rate]</span><span
|
|---|
| 5183 | class="cmtt-8"> =</span><span
|
|---|
| 5184 | class="cmtt-8"> read</span><span
|
|---|
| 5185 | class="cmtt-8"> an</span><span
|
|---|
| 5186 | class="cmtt-8"> unsigned</span><span
|
|---|
| 5187 | class="cmtt-8"> integer</span><span
|
|---|
| 5188 | class="cmtt-8"> of</span><span
|
|---|
| 5189 | class="cmtt-8"> 16</span><span
|
|---|
| 5190 | class="cmtt-8"> bits</span>
|
|---|
| 5191 | <br class="fancyvrb" /><a
|
|---|
| 5192 | id="x1-93006r3"></a><span
|
|---|
| 5193 | class="cmr-6">3</span><span
|
|---|
| 5194 | class="cmtt-8"> </span><span
|
|---|
| 5195 | class="cmtt-8"> 3)</span><span
|
|---|
| 5196 | class="cmtt-8"> [floor0</span><span
|
|---|
| 5197 | class="cmtt-8">_bark</span><span
|
|---|
| 5198 | class="cmtt-8">_map</span><span
|
|---|
| 5199 | class="cmtt-8">_size]</span><span
|
|---|
| 5200 | class="cmtt-8"> =</span><span
|
|---|
| 5201 | class="cmtt-8"> read</span><span
|
|---|
| 5202 | class="cmtt-8"> an</span><span
|
|---|
| 5203 | class="cmtt-8"> unsigned</span><span
|
|---|
| 5204 | class="cmtt-8"> integer</span><span
|
|---|
| 5205 | class="cmtt-8"> of</span><span
|
|---|
| 5206 | class="cmtt-8"> 16</span><span
|
|---|
| 5207 | class="cmtt-8"> bits</span><br class="fancyvrb" /><a
|
|---|
| 5208 | id="x1-93008r4"></a><span
|
|---|
| 5209 | class="cmr-6">4</span><span
|
|---|
| 5210 | class="cmtt-8"> </span><span
|
|---|
| 5211 | class="cmtt-8"> 4)</span><span
|
|---|
| 5212 | class="cmtt-8"> [floor0</span><span
|
|---|
| 5213 | class="cmtt-8">_amplitude</span><span
|
|---|
| 5214 | class="cmtt-8">_bits]</span><span
|
|---|
| 5215 | class="cmtt-8"> =</span><span
|
|---|
| 5216 | class="cmtt-8"> read</span><span
|
|---|
| 5217 | class="cmtt-8"> an</span><span
|
|---|
| 5218 | class="cmtt-8"> unsigned</span><span
|
|---|
| 5219 | class="cmtt-8"> integer</span><span
|
|---|
| 5220 | class="cmtt-8"> of</span><span
|
|---|
| 5221 | class="cmtt-8"> six</span><span
|
|---|
| 5222 | class="cmtt-8"> bits</span>
|
|---|
| 5223 | <br class="fancyvrb" /><a
|
|---|
| 5224 | id="x1-93010r5"></a><span
|
|---|
| 5225 | class="cmr-6">5</span><span
|
|---|
| 5226 | class="cmtt-8"> </span><span
|
|---|
| 5227 | class="cmtt-8"> 5)</span><span
|
|---|
| 5228 | class="cmtt-8"> [floor0</span><span
|
|---|
| 5229 | class="cmtt-8">_amplitude</span><span
|
|---|
| 5230 | class="cmtt-8">_offset]</span><span
|
|---|
| 5231 | class="cmtt-8"> =</span><span
|
|---|
| 5232 | class="cmtt-8"> read</span><span
|
|---|
| 5233 | class="cmtt-8"> an</span><span
|
|---|
| 5234 | class="cmtt-8"> unsigned</span><span
|
|---|
| 5235 | class="cmtt-8"> integer</span><span
|
|---|
| 5236 | class="cmtt-8"> of</span><span
|
|---|
| 5237 | class="cmtt-8"> eight</span><span
|
|---|
| 5238 | class="cmtt-8"> bits</span><br class="fancyvrb" /><a
|
|---|
| 5239 | id="x1-93012r6"></a><span
|
|---|
| 5240 | class="cmr-6">6</span><span
|
|---|
| 5241 | class="cmtt-8"> </span><span
|
|---|
| 5242 | class="cmtt-8"> 6)</span><span
|
|---|
| 5243 | class="cmtt-8"> [floor0</span><span
|
|---|
| 5244 | class="cmtt-8">_number</span><span
|
|---|
| 5245 | class="cmtt-8">_of</span><span
|
|---|
| 5246 | class="cmtt-8">_books]</span><span
|
|---|
| 5247 | class="cmtt-8"> =</span><span
|
|---|
| 5248 | class="cmtt-8"> read</span><span
|
|---|
| 5249 | class="cmtt-8"> an</span><span
|
|---|
| 5250 | class="cmtt-8"> unsigned</span><span
|
|---|
| 5251 | class="cmtt-8"> integer</span><span
|
|---|
| 5252 | class="cmtt-8"> of</span><span
|
|---|
| 5253 | class="cmtt-8"> four</span><span
|
|---|
| 5254 | class="cmtt-8"> bits</span><span
|
|---|
| 5255 | class="cmtt-8"> and</span><span
|
|---|
| 5256 | class="cmtt-8"> add</span><span
|
|---|
| 5257 | class="cmtt-8"> 1</span>
|
|---|
| 5258 | <br class="fancyvrb" /><a
|
|---|
| 5259 | id="x1-93014r7"></a><span
|
|---|
| 5260 | class="cmr-6">7</span><span
|
|---|
| 5261 | class="cmtt-8"> </span><span
|
|---|
| 5262 | class="cmtt-8"> 7)</span><span
|
|---|
| 5263 | class="cmtt-8"> array</span><span
|
|---|
| 5264 | class="cmtt-8"> [floor0</span><span
|
|---|
| 5265 | class="cmtt-8">_book</span><span
|
|---|
| 5266 | class="cmtt-8">_list]</span><span
|
|---|
| 5267 | class="cmtt-8"> =</span><span
|
|---|
| 5268 | class="cmtt-8"> read</span><span
|
|---|
| 5269 | class="cmtt-8"> a</span><span
|
|---|
| 5270 | class="cmtt-8"> list</span><span
|
|---|
| 5271 | class="cmtt-8"> of</span><span
|
|---|
| 5272 | class="cmtt-8"> [floor0</span><span
|
|---|
| 5273 | class="cmtt-8">_number</span><span
|
|---|
| 5274 | class="cmtt-8">_of</span><span
|
|---|
| 5275 | class="cmtt-8">_books]</span><span
|
|---|
| 5276 | class="cmtt-8"> unsigned</span><span
|
|---|
| 5277 | class="cmtt-8"> integers</span><span
|
|---|
| 5278 | class="cmtt-8"> of</span><span
|
|---|
| 5279 | class="cmtt-8"> eight</span><span
|
|---|
| 5280 | class="cmtt-8"> bits</span><span
|
|---|
| 5281 | class="cmtt-8"> each;</span></div>
|
|---|
| 5282 | <!--l. 39--><p class="noindent" >An end-of-packet condition during any of these bitstream reads renders this stream undecodable.
|
|---|
| 5283 | In addition, any element of the array <span
|
|---|
| 5284 | class="cmtt-12">[floor0</span><span
|
|---|
| 5285 | class="cmtt-12">_book</span><span
|
|---|
| 5286 | class="cmtt-12">_list] </span>that is greater than the maximum
|
|---|
| 5287 | codebook number for this bitstream is an error condition that also renders the stream
|
|---|
| 5288 |
|
|---|
| 5289 |
|
|---|
| 5290 |
|
|---|
| 5291 | undecodable.
|
|---|
| 5292 | <!--l. 47--><p class="noindent" >
|
|---|
| 5293 | <h5 class="subsubsectionHead"><span class="titlemark">6.2.2. </span> <a
|
|---|
| 5294 | id="x1-940006.2.2"></a>packet decode</h5>
|
|---|
| 5295 | <!--l. 49--><p class="noindent" >Extracting a floor0 curve from an audio packet consists of first decoding the curve
|
|---|
| 5296 | amplitude and <span
|
|---|
| 5297 | class="cmtt-12">[floor0</span><span
|
|---|
| 5298 | class="cmtt-12">_order] </span>LSP coefficient values from the bitstream, and then
|
|---|
| 5299 | computing the floor curve, which is defined as the frequency response of the decoded LSP
|
|---|
| 5300 | filter.
|
|---|
| 5301 | <!--l. 55--><p class="noindent" >Packet decode proceeds as follows:
|
|---|
| 5302 | <div class="fancyvrb" id="fancyvrb27"><a
|
|---|
| 5303 | id="x1-94002r1"></a><span
|
|---|
| 5304 | class="cmr-6">1</span><span
|
|---|
| 5305 | class="cmtt-8"> </span><span
|
|---|
| 5306 | class="cmtt-8"> 1)</span><span
|
|---|
| 5307 | class="cmtt-8"> [amplitude]</span><span
|
|---|
| 5308 | class="cmtt-8"> =</span><span
|
|---|
| 5309 | class="cmtt-8"> read</span><span
|
|---|
| 5310 | class="cmtt-8"> an</span><span
|
|---|
| 5311 | class="cmtt-8"> unsigned</span><span
|
|---|
| 5312 | class="cmtt-8"> integer</span><span
|
|---|
| 5313 | class="cmtt-8"> of</span><span
|
|---|
| 5314 | class="cmtt-8"> [floor0</span><span
|
|---|
| 5315 | class="cmtt-8">_amplitude</span><span
|
|---|
| 5316 | class="cmtt-8">_bits]</span><span
|
|---|
| 5317 | class="cmtt-8"> bits</span><br class="fancyvrb" /><a
|
|---|
| 5318 | id="x1-94004r2"></a><span
|
|---|
| 5319 | class="cmr-6">2</span><span
|
|---|
| 5320 | class="cmtt-8"> </span><span
|
|---|
| 5321 | class="cmtt-8"> 2)</span><span
|
|---|
| 5322 | class="cmtt-8"> if</span><span
|
|---|
| 5323 | class="cmtt-8"> (</span><span
|
|---|
| 5324 | class="cmtt-8"> [amplitude]</span><span
|
|---|
| 5325 | class="cmtt-8"> is</span><span
|
|---|
| 5326 | class="cmtt-8"> greater</span><span
|
|---|
| 5327 | class="cmtt-8"> than</span><span
|
|---|
| 5328 | class="cmtt-8"> zero</span><span
|
|---|
| 5329 | class="cmtt-8"> )</span><span
|
|---|
| 5330 | class="cmtt-8"> </span><span
|
|---|
| 5331 | class="cmsy-8">{</span>
|
|---|
| 5332 | <br class="fancyvrb" /><a
|
|---|
| 5333 | id="x1-94006r3"></a><span
|
|---|
| 5334 | class="cmr-6">3</span><span
|
|---|
| 5335 | class="cmtt-8"> </span><span
|
|---|
| 5336 | class="cmtt-8"> </span><span
|
|---|
| 5337 | class="cmtt-8"> </span><span
|
|---|
| 5338 | class="cmtt-8"> </span><span
|
|---|
| 5339 | class="cmtt-8"> </span><span
|
|---|
| 5340 | class="cmtt-8"> </span><span
|
|---|
| 5341 | class="cmtt-8"> 3)</span><span
|
|---|
| 5342 | class="cmtt-8"> [coefficients]</span><span
|
|---|
| 5343 | class="cmtt-8"> is</span><span
|
|---|
| 5344 | class="cmtt-8"> an</span><span
|
|---|
| 5345 | class="cmtt-8"> empty,</span><span
|
|---|
| 5346 | class="cmtt-8"> zero</span><span
|
|---|
| 5347 | class="cmtt-8"> length</span><span
|
|---|
| 5348 | class="cmtt-8"> vector</span><br class="fancyvrb" /><a
|
|---|
| 5349 | id="x1-94008r4"></a><span
|
|---|
| 5350 | class="cmr-6">4</span><span
|
|---|
| 5351 | class="cmtt-8"> </span><span
|
|---|
| 5352 | class="cmtt-8"> </span><span
|
|---|
| 5353 | class="cmtt-8"> </span><span
|
|---|
| 5354 | class="cmtt-8"> </span><span
|
|---|
| 5355 | class="cmtt-8"> </span><span
|
|---|
| 5356 | class="cmtt-8"> </span><span
|
|---|
| 5357 | class="cmtt-8"> 4)</span><span
|
|---|
| 5358 | class="cmtt-8"> [booknumber]</span><span
|
|---|
| 5359 | class="cmtt-8"> =</span><span
|
|---|
| 5360 | class="cmtt-8"> read</span><span
|
|---|
| 5361 | class="cmtt-8"> an</span><span
|
|---|
| 5362 | class="cmtt-8"> unsigned</span><span
|
|---|
| 5363 | class="cmtt-8"> integer</span><span
|
|---|
| 5364 | class="cmtt-8"> of</span><span
|
|---|
| 5365 | class="cmtt-8"> </span><a
|
|---|
| 5366 | href="#x1-1190009.2.1"><span
|
|---|
| 5367 | class="cmtt-8">ilog</span></a><span
|
|---|
| 5368 | class="cmtt-8">(</span><span
|
|---|
| 5369 | class="cmtt-8"> [floor0</span><span
|
|---|
| 5370 | class="cmtt-8">_number</span><span
|
|---|
| 5371 | class="cmtt-8">_of</span><span
|
|---|
| 5372 | class="cmtt-8">_books]</span><span
|
|---|
| 5373 | class="cmtt-8"> )</span><span
|
|---|
| 5374 | class="cmtt-8"> bits</span>
|
|---|
| 5375 | <br class="fancyvrb" /><a
|
|---|
| 5376 | id="x1-94010r5"></a><span
|
|---|
| 5377 | class="cmr-6">5</span><span
|
|---|
| 5378 | class="cmtt-8"> </span><span
|
|---|
| 5379 | class="cmtt-8"> </span><span
|
|---|
| 5380 | class="cmtt-8"> </span><span
|
|---|
| 5381 | class="cmtt-8"> </span><span
|
|---|
| 5382 | class="cmtt-8"> </span><span
|
|---|
| 5383 | class="cmtt-8"> </span><span
|
|---|
| 5384 | class="cmtt-8"> 5)</span><span
|
|---|
| 5385 | class="cmtt-8"> if</span><span
|
|---|
| 5386 | class="cmtt-8"> (</span><span
|
|---|
| 5387 | class="cmtt-8"> [booknumber]</span><span
|
|---|
| 5388 | class="cmtt-8"> is</span><span
|
|---|
| 5389 | class="cmtt-8"> greater</span><span
|
|---|
| 5390 | class="cmtt-8"> than</span><span
|
|---|
| 5391 | class="cmtt-8"> the</span><span
|
|---|
| 5392 | class="cmtt-8"> highest</span><span
|
|---|
| 5393 | class="cmtt-8"> number</span><span
|
|---|
| 5394 | class="cmtt-8"> decode</span><span
|
|---|
| 5395 | class="cmtt-8"> codebook</span><span
|
|---|
| 5396 | class="cmtt-8"> )</span><span
|
|---|
| 5397 | class="cmtt-8"> then</span><span
|
|---|
| 5398 | class="cmtt-8"> packet</span><span
|
|---|
| 5399 | class="cmtt-8"> is</span><span
|
|---|
| 5400 | class="cmtt-8"> undecodable</span><br class="fancyvrb" /><a
|
|---|
| 5401 | id="x1-94012r6"></a><span
|
|---|
| 5402 | class="cmr-6">6</span><span
|
|---|
| 5403 | class="cmtt-8"> </span><span
|
|---|
| 5404 | class="cmtt-8"> </span><span
|
|---|
| 5405 | class="cmtt-8"> </span><span
|
|---|
| 5406 | class="cmtt-8"> </span><span
|
|---|
| 5407 | class="cmtt-8"> </span><span
|
|---|
| 5408 | class="cmtt-8"> </span><span
|
|---|
| 5409 | class="cmtt-8"> 6)</span><span
|
|---|
| 5410 | class="cmtt-8"> [last]</span><span
|
|---|
| 5411 | class="cmtt-8"> =</span><span
|
|---|
| 5412 | class="cmtt-8"> zero;</span>
|
|---|
| 5413 | <br class="fancyvrb" /><a
|
|---|
| 5414 | id="x1-94014r7"></a><span
|
|---|
| 5415 | class="cmr-6">7</span><span
|
|---|
| 5416 | class="cmtt-8"> </span><span
|
|---|
| 5417 | class="cmtt-8"> </span><span
|
|---|
| 5418 | class="cmtt-8"> </span><span
|
|---|
| 5419 | class="cmtt-8"> </span><span
|
|---|
| 5420 | class="cmtt-8"> </span><span
|
|---|
| 5421 | class="cmtt-8"> </span><span
|
|---|
| 5422 | class="cmtt-8"> 7)</span><span
|
|---|
| 5423 | class="cmtt-8"> vector</span><span
|
|---|
| 5424 | class="cmtt-8"> [temp</span><span
|
|---|
| 5425 | class="cmtt-8">_vector]</span><span
|
|---|
| 5426 | class="cmtt-8"> =</span><span
|
|---|
| 5427 | class="cmtt-8"> read</span><span
|
|---|
| 5428 | class="cmtt-8"> vector</span><span
|
|---|
| 5429 | class="cmtt-8"> from</span><span
|
|---|
| 5430 | class="cmtt-8"> bitstream</span><span
|
|---|
| 5431 | class="cmtt-8"> using</span><span
|
|---|
| 5432 | class="cmtt-8"> codebook</span><span
|
|---|
| 5433 | class="cmtt-8"> number</span><span
|
|---|
| 5434 | class="cmtt-8"> [floor0</span><span
|
|---|
| 5435 | class="cmtt-8">_book</span><span
|
|---|
| 5436 | class="cmtt-8">_list]</span><span
|
|---|
| 5437 | class="cmtt-8"> element</span><span
|
|---|
| 5438 | class="cmtt-8"> [booknumber]</span><span
|
|---|
| 5439 | class="cmtt-8"> in</span><span
|
|---|
| 5440 | class="cmtt-8"> VQ</span><span
|
|---|
| 5441 | class="cmtt-8"> context.</span>
|
|---|
| 5442 | <br class="fancyvrb" /><a
|
|---|
| 5443 | id="x1-94016r8"></a><span
|
|---|
| 5444 | class="cmr-6">8</span><span
|
|---|
| 5445 | class="cmtt-8"> </span><span
|
|---|
| 5446 | class="cmtt-8"> </span><span
|
|---|
| 5447 | class="cmtt-8"> </span><span
|
|---|
| 5448 | class="cmtt-8"> </span><span
|
|---|
| 5449 | class="cmtt-8"> </span><span
|
|---|
| 5450 | class="cmtt-8"> </span><span
|
|---|
| 5451 | class="cmtt-8"> 8)</span><span
|
|---|
| 5452 | class="cmtt-8"> add</span><span
|
|---|
| 5453 | class="cmtt-8"> the</span><span
|
|---|
| 5454 | class="cmtt-8"> scalar</span><span
|
|---|
| 5455 | class="cmtt-8"> value</span><span
|
|---|
| 5456 | class="cmtt-8"> [last]</span><span
|
|---|
| 5457 | class="cmtt-8"> to</span><span
|
|---|
| 5458 | class="cmtt-8"> each</span><span
|
|---|
| 5459 | class="cmtt-8"> scalar</span><span
|
|---|
| 5460 | class="cmtt-8"> in</span><span
|
|---|
| 5461 | class="cmtt-8"> vector</span><span
|
|---|
| 5462 | class="cmtt-8"> [temp</span><span
|
|---|
| 5463 | class="cmtt-8">_vector]</span><br class="fancyvrb" /><a
|
|---|
| 5464 | id="x1-94018r9"></a><span
|
|---|
| 5465 | class="cmr-6">9</span><span
|
|---|
| 5466 | class="cmtt-8"> </span><span
|
|---|
| 5467 | class="cmtt-8"> </span><span
|
|---|
| 5468 | class="cmtt-8"> </span><span
|
|---|
| 5469 | class="cmtt-8"> </span><span
|
|---|
| 5470 | class="cmtt-8"> </span><span
|
|---|
| 5471 | class="cmtt-8"> </span><span
|
|---|
| 5472 | class="cmtt-8"> 9)</span><span
|
|---|
| 5473 | class="cmtt-8"> [last]</span><span
|
|---|
| 5474 | class="cmtt-8"> =</span><span
|
|---|
| 5475 | class="cmtt-8"> the</span><span
|
|---|
| 5476 | class="cmtt-8"> value</span><span
|
|---|
| 5477 | class="cmtt-8"> of</span><span
|
|---|
| 5478 | class="cmtt-8"> the</span><span
|
|---|
| 5479 | class="cmtt-8"> last</span><span
|
|---|
| 5480 | class="cmtt-8"> scalar</span><span
|
|---|
| 5481 | class="cmtt-8"> in</span><span
|
|---|
| 5482 | class="cmtt-8"> vector</span><span
|
|---|
| 5483 | class="cmtt-8"> [temp</span><span
|
|---|
| 5484 | class="cmtt-8">_vector]</span>
|
|---|
| 5485 | <br class="fancyvrb" /><a
|
|---|
| 5486 | id="x1-94020r10"></a><span
|
|---|
| 5487 | class="cmr-6">10</span><span
|
|---|
| 5488 | class="cmtt-8"> </span><span
|
|---|
| 5489 | class="cmtt-8"> </span><span
|
|---|
| 5490 | class="cmtt-8"> </span><span
|
|---|
| 5491 | class="cmtt-8"> </span><span
|
|---|
| 5492 | class="cmtt-8"> </span><span
|
|---|
| 5493 | class="cmtt-8"> 10)</span><span
|
|---|
| 5494 | class="cmtt-8"> concatenate</span><span
|
|---|
| 5495 | class="cmtt-8"> [temp</span><span
|
|---|
| 5496 | class="cmtt-8">_vector]</span><span
|
|---|
| 5497 | class="cmtt-8"> onto</span><span
|
|---|
| 5498 | class="cmtt-8"> the</span><span
|
|---|
| 5499 | class="cmtt-8"> end</span><span
|
|---|
| 5500 | class="cmtt-8"> of</span><span
|
|---|
| 5501 | class="cmtt-8"> the</span><span
|
|---|
| 5502 | class="cmtt-8"> [coefficients]</span><span
|
|---|
| 5503 | class="cmtt-8"> vector</span>
|
|---|
| 5504 | <br class="fancyvrb" /><a
|
|---|
| 5505 | id="x1-94022r11"></a><span
|
|---|
| 5506 | class="cmr-6">11</span><span
|
|---|
| 5507 | class="cmtt-8"> </span><span
|
|---|
| 5508 | class="cmtt-8"> </span><span
|
|---|
| 5509 | class="cmtt-8"> </span><span
|
|---|
| 5510 | class="cmtt-8"> </span><span
|
|---|
| 5511 | class="cmtt-8"> </span><span
|
|---|
| 5512 | class="cmtt-8"> 11)</span><span
|
|---|
| 5513 | class="cmtt-8"> if</span><span
|
|---|
| 5514 | class="cmtt-8"> (length</span><span
|
|---|
| 5515 | class="cmtt-8"> of</span><span
|
|---|
| 5516 | class="cmtt-8"> vector</span><span
|
|---|
| 5517 | class="cmtt-8"> [coefficients]</span><span
|
|---|
| 5518 | class="cmtt-8"> is</span><span
|
|---|
| 5519 | class="cmtt-8"> less</span><span
|
|---|
| 5520 | class="cmtt-8"> than</span><span
|
|---|
| 5521 | class="cmtt-8"> [floor0</span><span
|
|---|
| 5522 | class="cmtt-8">_order],</span><span
|
|---|
| 5523 | class="cmtt-8"> continue</span><span
|
|---|
| 5524 | class="cmtt-8"> at</span><span
|
|---|
| 5525 | class="cmtt-8"> step</span><span
|
|---|
| 5526 | class="cmtt-8"> 6</span><br class="fancyvrb" /><a
|
|---|
| 5527 | id="x1-94024r12"></a><span
|
|---|
| 5528 | class="cmr-6">12</span><br class="fancyvrb" /><a
|
|---|
| 5529 | id="x1-94026r13"></a><span
|
|---|
| 5530 | class="cmr-6">13</span><span
|
|---|
| 5531 | class="cmtt-8"> </span><span
|
|---|
| 5532 | class="cmtt-8"> </span><span
|
|---|
| 5533 | class="cmtt-8"> </span><span
|
|---|
| 5534 | class="cmtt-8"> </span><span
|
|---|
| 5535 | class="cmtt-8"> </span><span
|
|---|
| 5536 | class="cmsy-8">}</span><br class="fancyvrb" /><a
|
|---|
| 5537 | id="x1-94028r14"></a><span
|
|---|
| 5538 | class="cmr-6">14</span><br class="fancyvrb" /><a
|
|---|
| 5539 | id="x1-94030r15"></a><span
|
|---|
| 5540 | class="cmr-6">15</span><span
|
|---|
| 5541 | class="cmtt-8"> 12)</span><span
|
|---|
| 5542 | class="cmtt-8"> done.</span><br class="fancyvrb" /><a
|
|---|
| 5543 | id="x1-94032r16"></a><span
|
|---|
| 5544 | class="cmr-6">16</span></div>
|
|---|
| 5545 | <!--l. 75--><p class="noindent" >Take note of the following properties of decode:
|
|---|
| 5546 | <ul class="itemize1">
|
|---|
| 5547 | <li class="itemize">An <span
|
|---|
| 5548 | class="cmtt-12">[amplitude] </span>value of zero must result in a return code that indicates this channel
|
|---|
| 5549 | is unused in this frame (the output of the channel will be all-zeroes in synthesis).
|
|---|
| 5550 | Several later stages of decode don’t occur for an unused channel.
|
|---|
| 5551 | </li>
|
|---|
| 5552 | <li class="itemize">An end-of-packet condition during decode should be considered a nominal occruence;
|
|---|
| 5553 | if end-of-packet is reached during any read operation above, floor decode is to return
|
|---|
| 5554 | ’unused’ status as if the <span
|
|---|
| 5555 | class="cmtt-12">[amplitude] </span>value had read zero at the beginning of decode.
|
|---|
| 5556 | </li>
|
|---|
| 5557 | <li class="itemize">The book number used for decode can, in fact, be stored in the bitstream in <a
|
|---|
| 5558 | href="#x1-1190009.2.1">ilog</a>(
|
|---|
| 5559 | <span
|
|---|
| 5560 | class="cmtt-12">[floor0</span><span
|
|---|
| 5561 | class="cmtt-12">_number</span><span
|
|---|
| 5562 | class="cmtt-12">_of</span><span
|
|---|
| 5563 | class="cmtt-12">_books] </span>- 1 ) bits. Nevertheless, the above specification is correct
|
|---|
| 5564 | and values greater than the maximum possible book value are reserved.
|
|---|
| 5565 | </li>
|
|---|
| 5566 | <li class="itemize">The number of scalars read into the vector <span
|
|---|
| 5567 | class="cmtt-12">[coefficients] </span>may be greater
|
|---|
| 5568 | than <span
|
|---|
| 5569 | class="cmtt-12">[floor0</span><span
|
|---|
| 5570 | class="cmtt-12">_order]</span>, the number actually required for curve computation. For
|
|---|
| 5571 | example, if the VQ codebook used for the floor currently being decoded has a
|
|---|
| 5572 | <span
|
|---|
| 5573 | class="cmtt-12">[codebook</span><span
|
|---|
| 5574 | class="cmtt-12">_dimensions] </span>value of three and <span
|
|---|
| 5575 | class="cmtt-12">[floor0</span><span
|
|---|
| 5576 | class="cmtt-12">_order] </span>is ten, the only way to
|
|---|
| 5577 | fill all the needed scalars in <span
|
|---|
| 5578 | class="cmtt-12">[coefficients] </span>is to to read a total of twelve scalars
|
|---|
| 5579 | as four vectors of three scalars each. This is not an error condition, and care must
|
|---|
| 5580 | be taken not to allow a buffer overflow in decode. The extra values are not used and
|
|---|
| 5581 |
|
|---|
| 5582 |
|
|---|
| 5583 |
|
|---|
| 5584 | may be ignored or discarded.</li></ul>
|
|---|
| 5585 | <!--l. 103--><p class="noindent" >
|
|---|
| 5586 | <h5 class="subsubsectionHead"><span class="titlemark">6.2.3. </span> <a
|
|---|
| 5587 | id="x1-950006.2.3"></a>curve computation</h5>
|
|---|
| 5588 | <!--l. 105--><p class="noindent" >Given an <span
|
|---|
| 5589 | class="cmtt-12">[amplitude] </span>integer and <span
|
|---|
| 5590 | class="cmtt-12">[coefficients] </span>vector from packet decode as well as
|
|---|
| 5591 | the [floor0_order], [floor0_rate], [floor0_bark_map_size], [floor0_amplitude_bits] and
|
|---|
| 5592 | [floor0_amplitude_offset] values from floor setup, and an output vector size <span
|
|---|
| 5593 | class="cmtt-12">[n] </span>specified by the
|
|---|
| 5594 | decode process, we compute a floor output vector.
|
|---|
| 5595 | <!--l. 112--><p class="noindent" >If the value <span
|
|---|
| 5596 | class="cmtt-12">[amplitude] </span>is zero, the return value is a length <span
|
|---|
| 5597 | class="cmtt-12">[n] </span>vector with all-zero
|
|---|
| 5598 | scalars. Otherwise, begin by assuming the following definitions for the given vector to be
|
|---|
| 5599 | synthesized:
|
|---|
| 5600 | <center class="par-math-display" >
|
|---|
| 5601 | <img
|
|---|
| 5602 | src="Vorbis_I_spec7x.png" alt=" {
|
|---|
| 5603 | min (floor0xbarkxmapxsize - 1,f oobar) for i ∈ [0, n - 1]
|
|---|
| 5604 | mapi = - 1 for i = n
|
|---|
| 5605 | " class="par-math-display" ></center>
|
|---|
| 5606 | <!--l. 127--><p class="nopar" >
|
|---|
| 5607 | <!--l. 129--><p class="noindent" >where
|
|---|
| 5608 | <center class="par-math-display" >
|
|---|
| 5609 | <img
|
|---|
| 5610 | src="Vorbis_I_spec8x.png" alt=" ⌊ ( floor0xrate ⋅ i) floor0xbarkxmapxsize ⌋
|
|---|
| 5611 | f oobar = bark ---------------- ⋅------------------------
|
|---|
| 5612 | 2n bark(.5 ⋅ floor0xrate )
|
|---|
| 5613 | " class="par-math-display" ></center>
|
|---|
| 5614 | <!--l. 136--><p class="nopar" >
|
|---|
| 5615 | <!--l. 138--><p class="noindent" >and
|
|---|
| 5616 | <center class="par-math-display" >
|
|---|
| 5617 | <img
|
|---|
| 5618 | src="Vorbis_I_spec9x.png" alt="bark(x) = 13.1arctan (.00074x ) + 2.24 arctan(.0000000185x2 ) + .0001x
|
|---|
| 5619 | " class="par-math-display" ></center>
|
|---|
| 5620 | <!--l. 142--><p class="nopar" >
|
|---|
| 5621 |
|
|---|
| 5622 |
|
|---|
| 5623 |
|
|---|
| 5624 | <!--l. 144--><p class="noindent" >The above is used to synthesize the LSP curve on a Bark-scale frequency axis, then map the
|
|---|
| 5625 | result to a linear-scale frequency axis. Similarly, the below calculation synthesizes the output
|
|---|
| 5626 | LSP curve <span
|
|---|
| 5627 | class="cmtt-12">[output] </span>on a log (dB) amplitude scale, mapping it to linear amplitude in the last
|
|---|
| 5628 | step:
|
|---|
| 5629 | <!--l. 150--><p class="noindent" >
|
|---|
| 5630 | <dl class="enumerate-enumitem"><dt class="enumerate-enumitem">
|
|---|
| 5631 | 1. </dt><dd
|
|---|
| 5632 | class="enumerate-enumitem"><span
|
|---|
| 5633 | class="cmtt-12">[i] </span>= 0
|
|---|
| 5634 | </dd><dt class="enumerate-enumitem">
|
|---|
| 5635 | 2. </dt><dd
|
|---|
| 5636 | class="enumerate-enumitem"><span
|
|---|
| 5637 | class="cmtt-12">[</span><span
|
|---|
| 5638 | class="cmmi-12">ω</span><span
|
|---|
| 5639 | class="cmtt-12">] </span>= <span
|
|---|
| 5640 | class="cmmi-12">π </span>* map element <span
|
|---|
| 5641 | class="cmtt-12">[i] </span>/ <span
|
|---|
| 5642 | class="cmtt-12">[floor0</span><span
|
|---|
| 5643 | class="cmtt-12">_bark</span><span
|
|---|
| 5644 | class="cmtt-12">_map</span><span
|
|---|
| 5645 | class="cmtt-12">_size]</span>
|
|---|
| 5646 | </dd><dt class="enumerate-enumitem">
|
|---|
| 5647 | 3. </dt><dd
|
|---|
| 5648 | class="enumerate-enumitem">if ( <span
|
|---|
| 5649 | class="cmtt-12">[floor0</span><span
|
|---|
| 5650 | class="cmtt-12">_order] </span>is odd )
|
|---|
| 5651 | <dl class="enumerate-enumitem"><dt class="enumerate-enumitem">
|
|---|
| 5652 | a) </dt><dd
|
|---|
| 5653 | class="enumerate-enumitem">calculate <span
|
|---|
| 5654 | class="cmtt-12">[p] </span>and <span
|
|---|
| 5655 | class="cmtt-12">[q] </span>according to: <div class="eqnarray">
|
|---|
| 5656 | <center class="math-display" >
|
|---|
| 5657 | <img
|
|---|
| 5658 | src="Vorbis_I_spec10x.png" alt=" floor0∏x2order-3
|
|---|
| 5659 | p = (1 - cos2ω) 4(cos([coefficients ]2j+1) - cosω )2
|
|---|
| 5660 | j=0
|
|---|
| 5661 | floor0xorder-1
|
|---|
| 5662 | 1 ∏2 2
|
|---|
| 5663 | q = -- 4(cos([coefficients ]2j) - cosω )
|
|---|
| 5664 | 4 j=0
|
|---|
| 5665 | " class="math-display" ></center>
|
|---|
| 5666 | </div>
|
|---|
| 5667 | </dd></dl>
|
|---|
| 5668 | <!--l. 161--><p class="noindent" >else <span
|
|---|
| 5669 | class="cmtt-12">[floor0</span><span
|
|---|
| 5670 | class="cmtt-12">_order] </span>is even
|
|---|
| 5671 | <dl class="enumerate-enumitem"><dt class="enumerate-enumitem">
|
|---|
| 5672 | a) </dt><dd
|
|---|
| 5673 | class="enumerate-enumitem">calculate <span
|
|---|
| 5674 | class="cmtt-12">[p] </span>and <span
|
|---|
| 5675 | class="cmtt-12">[q] </span>according to: <div class="eqnarray">
|
|---|
| 5676 |
|
|---|
| 5677 |
|
|---|
| 5678 |
|
|---|
| 5679 | <center class="math-display" >
|
|---|
| 5680 | <img
|
|---|
| 5681 | src="Vorbis_I_spec11x.png" alt=" floor0x∏o2rder-2
|
|---|
| 5682 | p = (1---cosω-) 4(cos([coefficients ]2j+1) - cosω)2
|
|---|
| 5683 | 2 j=0
|
|---|
| 5684 | floor0xorder--2
|
|---|
| 5685 | (1 + cosω ) ∏2 2
|
|---|
| 5686 | q = ----------- 4(cos([coefficients ]2j) - cos ω)
|
|---|
| 5687 | 2 j=0
|
|---|
| 5688 | " class="math-display" ></center>
|
|---|
| 5689 | </div>
|
|---|
| 5690 | </dd></dl>
|
|---|
| 5691 | </dd><dt class="enumerate-enumitem">
|
|---|
| 5692 | 4. </dt><dd
|
|---|
| 5693 | class="enumerate-enumitem">calculate <span
|
|---|
| 5694 | class="cmtt-12">[linear</span><span
|
|---|
| 5695 | class="cmtt-12">_floor</span><span
|
|---|
| 5696 | class="cmtt-12">_value] </span>according to:
|
|---|
| 5697 | <center class="math-display" >
|
|---|
| 5698 | <img
|
|---|
| 5699 | src="Vorbis_I_spec12x.png" alt=" ( ( ))
|
|---|
| 5700 | amplitude ⋅ floor0xamplitutexoffset
|
|---|
| 5701 | exp .11512925 ------floor0xamplitudexbits-----√----------- floor0xamplitudexoffset
|
|---|
| 5702 | (2 - 1) p + q
|
|---|
| 5703 | " class="math-display" ></center>
|
|---|
| 5704 | <!--l. 176--><p class="nopar" >
|
|---|
| 5705 | </dd><dt class="enumerate-enumitem">
|
|---|
| 5706 | 5. </dt><dd
|
|---|
| 5707 | class="enumerate-enumitem"><span
|
|---|
| 5708 | class="cmtt-12">[iteration</span><span
|
|---|
| 5709 | class="cmtt-12">_condition] </span>= map element <span
|
|---|
| 5710 | class="cmtt-12">[i]</span>
|
|---|
| 5711 | </dd><dt class="enumerate-enumitem">
|
|---|
| 5712 | 6. </dt><dd
|
|---|
| 5713 | class="enumerate-enumitem"><span
|
|---|
| 5714 | class="cmtt-12">[output] </span>element <span
|
|---|
| 5715 | class="cmtt-12">[i] </span>= <span
|
|---|
| 5716 | class="cmtt-12">[linear</span><span
|
|---|
| 5717 | class="cmtt-12">_floor</span><span
|
|---|
| 5718 | class="cmtt-12">_value]</span>
|
|---|
| 5719 | </dd><dt class="enumerate-enumitem">
|
|---|
| 5720 | 7. </dt><dd
|
|---|
| 5721 | class="enumerate-enumitem">increment <span
|
|---|
| 5722 | class="cmtt-12">[i]</span>
|
|---|
| 5723 | </dd><dt class="enumerate-enumitem">
|
|---|
| 5724 | 8. </dt><dd
|
|---|
| 5725 | class="enumerate-enumitem">if ( map element <span
|
|---|
| 5726 | class="cmtt-12">[i] </span>is equal to <span
|
|---|
| 5727 | class="cmtt-12">[iteration</span><span
|
|---|
| 5728 | class="cmtt-12">_condition] </span>) continue at step
|
|---|
| 5729 | 5
|
|---|
| 5730 | </dd><dt class="enumerate-enumitem">
|
|---|
| 5731 | 9. </dt><dd
|
|---|
| 5732 | class="enumerate-enumitem">if ( <span
|
|---|
| 5733 | class="cmtt-12">[i] </span>is less than <span
|
|---|
| 5734 | class="cmtt-12">[n] </span>) continue at step 2
|
|---|
| 5735 |
|
|---|
| 5736 |
|
|---|
| 5737 |
|
|---|
| 5738 | </dd><dt class="enumerate-enumitem">
|
|---|
| 5739 | 10. </dt><dd
|
|---|
| 5740 | class="enumerate-enumitem">done</dd></dl>
|
|---|
| 5741 | <!--l. 186--><p class="noindent" ><span class="paragraphHead"><a
|
|---|
| 5742 | id="x1-960006.2.3"></a><span
|
|---|
| 5743 | class="cmbx-12">Errata 20150227: Bark scale computation</span></span>
|
|---|
| 5744 | Due to a typo when typesetting this version of the specification from the original HTML
|
|---|
| 5745 | document, the Bark scale computation previously erroneously read:
|
|---|
| 5746 | <center class="par-math-display" >
|
|---|
| 5747 | <img
|
|---|
| 5748 | src="Vorbis_I_spec13x.png" alt="bark(x) = 13.1arctan (.00074x ) + 2.24 arctan(.0000000185x2 + .0001x )
|
|---|
| 5749 | " class="par-math-display" ></center>
|
|---|
| 5750 | <!--l. 194--><p class="nopar" >
|
|---|
| 5751 | <!--l. 196--><p class="noindent" >Note that the last parenthesis is misplaced. This document now uses the correct equation as it
|
|---|
| 5752 | appeared in the original HTML spec document:
|
|---|
| 5753 | <center class="par-math-display" >
|
|---|
| 5754 | <img
|
|---|
| 5755 | src="Vorbis_I_spec14x.png" alt="bark(x) = 13.1arctan (.00074x ) + 2.24 arctan(.0000000185x2 ) + .0001x
|
|---|
| 5756 | " class="par-math-display" ></center>
|
|---|
| 5757 | <!--l. 200--><p class="nopar" >
|
|---|
| 5758 |
|
|---|
| 5759 |
|
|---|
| 5760 |
|
|---|
| 5761 |
|
|---|
| 5762 |
|
|---|
| 5763 |
|
|---|
| 5764 | <h3 class="sectionHead"><span class="titlemark">7. </span> <a
|
|---|
| 5765 | id="x1-970007"></a>Floor type 1 setup and decode</h3>
|
|---|
| 5766 | <!--l. 5--><p class="noindent" >
|
|---|
| 5767 | <h4 class="subsectionHead"><span class="titlemark">7.1. </span> <a
|
|---|
| 5768 | id="x1-980007.1"></a>Overview</h4>
|
|---|
| 5769 | <!--l. 7--><p class="noindent" >Vorbis floor type one uses a piecewise straight-line representation to encode a spectral envelope
|
|---|
| 5770 | curve. The representation plots this curve mechanically on a linear frequency axis and a
|
|---|
| 5771 | logarithmic (dB) amplitude axis. The integer plotting algorithm used is similar to Bresenham’s
|
|---|
| 5772 | algorithm.
|
|---|
| 5773 | <!--l. 15--><p class="noindent" >
|
|---|
| 5774 | <h4 class="subsectionHead"><span class="titlemark">7.2. </span> <a
|
|---|
| 5775 | id="x1-990007.2"></a>Floor 1 format</h4>
|
|---|
| 5776 | <!--l. 17--><p class="noindent" >
|
|---|
| 5777 | <h5 class="subsubsectionHead"><span class="titlemark">7.2.1. </span> <a
|
|---|
| 5778 | id="x1-1000007.2.1"></a>model</h5>
|
|---|
| 5779 | <!--l. 19--><p class="noindent" >Floor type one represents a spectral curve as a series of line segments. Synthesis constructs a
|
|---|
| 5780 | floor curve using iterative prediction in a process roughly equivalent to the following simplified
|
|---|
| 5781 | description:
|
|---|
| 5782 | <ul class="itemize1">
|
|---|
| 5783 | <li class="itemize">the first line segment (base case) is a logical line spanning from x˙0,y˙0 to x˙1,y˙1
|
|---|
| 5784 | where in the base case x˙0=0 and x˙1=[n], the full range of the spectral floor to be
|
|---|
| 5785 | computed.
|
|---|
| 5786 | </li>
|
|---|
| 5787 | <li class="itemize">the induction step chooses a point x˙new within an existing logical line segment and
|
|---|
| 5788 | produces a y˙new value at that point computed from the existing line’s y value at
|
|---|
| 5789 | x˙new (as plotted by the line) and a difference value decoded from the bitstream
|
|---|
| 5790 | packet.
|
|---|
| 5791 |
|
|---|
| 5792 |
|
|---|
| 5793 |
|
|---|
| 5794 | </li>
|
|---|
| 5795 | <li class="itemize">floor computation produces two new line segments, one running from x˙0,y˙0 to
|
|---|
| 5796 | x˙new,y˙new and from x˙new,y˙new to x˙1,y˙1. This step is performed logically even if
|
|---|
| 5797 | y˙new represents no change to the amplitude value at x˙new so that later refinement
|
|---|
| 5798 | is additionally bounded at x˙new.
|
|---|
| 5799 | </li>
|
|---|
| 5800 | <li class="itemize">the induction step repeats, using a list of x values specified in the codec setup header
|
|---|
| 5801 | at floor 1 initialization time. Computation is completed at the end of the x value list.
|
|---|
| 5802 | </li></ul>
|
|---|
| 5803 | <!--l. 47--><p class="noindent" >Consider the following example, with values chosen for ease of understanding rather than
|
|---|
| 5804 | representing typical configuration:
|
|---|
| 5805 | <!--l. 50--><p class="noindent" >For the below example, we assume a floor setup with an [n] of 128. The list of selected X values
|
|---|
| 5806 | in increasing order is 0,16,32,48,64,80,96,112 and 128. In list order, the values interleave as 0,
|
|---|
| 5807 | 128, 64, 32, 96, 16, 48, 80 and 112. The corresponding list-order Y values as decoded from an
|
|---|
| 5808 | example packet are 110, 20, -5, -45, 0, -25, -10, 30 and -10. We compute the floor in the following
|
|---|
| 5809 | way, beginning with the first line:
|
|---|
| 5810 | <div class="center"
|
|---|
| 5811 | >
|
|---|
| 5812 | <!--l. 58--><p class="noindent" >
|
|---|
| 5813 |
|
|---|
| 5814 | <!--l. 59--><p class="noindent" ><img
|
|---|
| 5815 | src="floor1-1.png" alt="PIC"
|
|---|
| 5816 | >
|
|---|
| 5817 | <br /> <div class="caption"
|
|---|
| 5818 | ><span class="id">Figure 7: </span><span
|
|---|
| 5819 | class="content">graph of example floor</span></div><!--tex4ht:label?: x1-1000017 -->
|
|---|
| 5820 | </div>
|
|---|
| 5821 | <!--l. 63--><p class="noindent" >We now draw new logical lines to reflect the correction to new˙Y, and iterate for X positions 32
|
|---|
| 5822 | and 96:
|
|---|
| 5823 | <div class="center"
|
|---|
| 5824 | >
|
|---|
| 5825 | <!--l. 66--><p class="noindent" >
|
|---|
| 5826 |
|
|---|
| 5827 | <!--l. 67--><p class="noindent" ><img
|
|---|
| 5828 | src="floor1-2.png" alt="PIC"
|
|---|
| 5829 | >
|
|---|
| 5830 | <br /> <div class="caption"
|
|---|
| 5831 | ><span class="id">Figure 8: </span><span
|
|---|
| 5832 | class="content">graph of example floor</span></div><!--tex4ht:label?: x1-1000028 -->
|
|---|
| 5833 | </div>
|
|---|
| 5834 | <!--l. 71--><p class="noindent" >Although the new Y value at X position 96 is unchanged, it is still used later as an endpoint for
|
|---|
| 5835 | further refinement. From here on, the pattern should be clear; we complete the floor computation
|
|---|
| 5836 | as follows:
|
|---|
| 5837 |
|
|---|
| 5838 |
|
|---|
| 5839 |
|
|---|
| 5840 | <div class="center"
|
|---|
| 5841 | >
|
|---|
| 5842 | <!--l. 75--><p class="noindent" >
|
|---|
| 5843 |
|
|---|
| 5844 | <!--l. 76--><p class="noindent" ><img
|
|---|
| 5845 | src="floor1-3.png" alt="PIC"
|
|---|
| 5846 | >
|
|---|
| 5847 | <br /> <div class="caption"
|
|---|
| 5848 | ><span class="id">Figure 9: </span><span
|
|---|
| 5849 | class="content">graph of example floor</span></div><!--tex4ht:label?: x1-1000039 -->
|
|---|
| 5850 | </div>
|
|---|
| 5851 | <div class="center"
|
|---|
| 5852 | >
|
|---|
| 5853 | <!--l. 80--><p class="noindent" >
|
|---|
| 5854 |
|
|---|
| 5855 | <!--l. 81--><p class="noindent" ><img
|
|---|
| 5856 | src="floor1-4.png" alt="PIC"
|
|---|
| 5857 | >
|
|---|
| 5858 | <br /> <div class="caption"
|
|---|
| 5859 | ><span class="id">Figure 10: </span><span
|
|---|
| 5860 | class="content">graph of example floor</span></div><!--tex4ht:label?: x1-10000410 -->
|
|---|
| 5861 | </div>
|
|---|
| 5862 | <!--l. 85--><p class="noindent" >A more efficient algorithm with carefully defined integer rounding behavior is used for actual
|
|---|
| 5863 | decode, as described later. The actual algorithm splits Y value computation and line plotting
|
|---|
| 5864 | into two steps with modifications to the above algorithm to eliminate noise accumulation
|
|---|
| 5865 | through integer roundoff/truncation.
|
|---|
| 5866 | <!--l. 93--><p class="noindent" >
|
|---|
| 5867 | <h5 class="subsubsectionHead"><span class="titlemark">7.2.2. </span> <a
|
|---|
| 5868 | id="x1-1010007.2.2"></a>header decode</h5>
|
|---|
| 5869 | <!--l. 95--><p class="noindent" >A list of floor X values is stored in the packet header in interleaved format (used in list order
|
|---|
| 5870 | during packet decode and synthesis). This list is split into partitions, and each partition is
|
|---|
| 5871 | assigned to a partition class. X positions 0 and [n] are implicit and do not belong to an explicit
|
|---|
| 5872 | partition or partition class.
|
|---|
| 5873 | <!--l. 101--><p class="noindent" >A partition class consists of a representation vector width (the number of Y values which
|
|---|
| 5874 | the partition class encodes at once), a ’subclass’ value representing the number of
|
|---|
| 5875 | alternate entropy books the partition class may use in representing Y values, the list of
|
|---|
| 5876 | [subclass] books and a master book used to encode which alternate books were chosen
|
|---|
| 5877 | for representation in a given packet. The master/subclass mechanism is meant to be
|
|---|
| 5878 | used as a flexible representation cascade while still using codebooks only in a scalar
|
|---|
| 5879 | context.
|
|---|
| 5880 |
|
|---|
| 5881 |
|
|---|
| 5882 |
|
|---|
| 5883 | <!--l. 111--><p class="noindent" >
|
|---|
| 5884 | <div class="fancyvrb" id="fancyvrb28"><a
|
|---|
| 5885 | id="x1-101002r1"></a><span
|
|---|
| 5886 | class="cmr-6">1</span><br class="fancyvrb" /><a
|
|---|
| 5887 | id="x1-101004r2"></a><span
|
|---|
| 5888 | class="cmr-6">2</span><span
|
|---|
| 5889 | class="cmtt-8"> </span><span
|
|---|
| 5890 | class="cmtt-8"> 1)</span><span
|
|---|
| 5891 | class="cmtt-8"> [floor1</span><span
|
|---|
| 5892 | class="cmtt-8">_partitions]</span><span
|
|---|
| 5893 | class="cmtt-8"> =</span><span
|
|---|
| 5894 | class="cmtt-8"> read</span><span
|
|---|
| 5895 | class="cmtt-8"> 5</span><span
|
|---|
| 5896 | class="cmtt-8"> bits</span><span
|
|---|
| 5897 | class="cmtt-8"> as</span><span
|
|---|
| 5898 | class="cmtt-8"> unsigned</span><span
|
|---|
| 5899 | class="cmtt-8"> integer</span><br class="fancyvrb" /><a
|
|---|
| 5900 | id="x1-101006r3"></a><span
|
|---|
| 5901 | class="cmr-6">3</span><span
|
|---|
| 5902 | class="cmtt-8"> </span><span
|
|---|
| 5903 | class="cmtt-8"> 2)</span><span
|
|---|
| 5904 | class="cmtt-8"> [maximum</span><span
|
|---|
| 5905 | class="cmtt-8">_class]</span><span
|
|---|
| 5906 | class="cmtt-8"> =</span><span
|
|---|
| 5907 | class="cmtt-8"> -1</span><br class="fancyvrb" /><a
|
|---|
| 5908 | id="x1-101008r4"></a><span
|
|---|
| 5909 | class="cmr-6">4</span><span
|
|---|
| 5910 | class="cmtt-8"> </span><span
|
|---|
| 5911 | class="cmtt-8"> 3)</span><span
|
|---|
| 5912 | class="cmtt-8"> iterate</span><span
|
|---|
| 5913 | class="cmtt-8"> [i]</span><span
|
|---|
| 5914 | class="cmtt-8"> over</span><span
|
|---|
| 5915 | class="cmtt-8"> the</span><span
|
|---|
| 5916 | class="cmtt-8"> range</span><span
|
|---|
| 5917 | class="cmtt-8"> 0</span><span
|
|---|
| 5918 | class="cmtt-8"> ...</span><span
|
|---|
| 5919 | class="cmtt-8"> [floor1</span><span
|
|---|
| 5920 | class="cmtt-8">_partitions]-1</span><span
|
|---|
| 5921 | class="cmtt-8"> </span><span
|
|---|
| 5922 | class="cmsy-8">{</span><br class="fancyvrb" /><a
|
|---|
| 5923 | id="x1-101010r5"></a><span
|
|---|
| 5924 | class="cmr-6">5</span>
|
|---|
| 5925 | <br class="fancyvrb" /><a
|
|---|
| 5926 | id="x1-101012r6"></a><span
|
|---|
| 5927 | class="cmr-6">6</span><span
|
|---|
| 5928 | class="cmtt-8"> </span><span
|
|---|
| 5929 | class="cmtt-8"> </span><span
|
|---|
| 5930 | class="cmtt-8"> </span><span
|
|---|
| 5931 | class="cmtt-8"> </span><span
|
|---|
| 5932 | class="cmtt-8"> </span><span
|
|---|
| 5933 | class="cmtt-8"> </span><span
|
|---|
| 5934 | class="cmtt-8"> </span><span
|
|---|
| 5935 | class="cmtt-8"> 4)</span><span
|
|---|
| 5936 | class="cmtt-8"> vector</span><span
|
|---|
| 5937 | class="cmtt-8"> [floor1</span><span
|
|---|
| 5938 | class="cmtt-8">_partition</span><span
|
|---|
| 5939 | class="cmtt-8">_class</span><span
|
|---|
| 5940 | class="cmtt-8">_list]</span><span
|
|---|
| 5941 | class="cmtt-8"> element</span><span
|
|---|
| 5942 | class="cmtt-8"> [i]</span><span
|
|---|
| 5943 | class="cmtt-8"> =</span><span
|
|---|
| 5944 | class="cmtt-8"> read</span><span
|
|---|
| 5945 | class="cmtt-8"> 4</span><span
|
|---|
| 5946 | class="cmtt-8"> bits</span><span
|
|---|
| 5947 | class="cmtt-8"> as</span><span
|
|---|
| 5948 | class="cmtt-8"> unsigned</span><span
|
|---|
| 5949 | class="cmtt-8"> integer</span><br class="fancyvrb" /><a
|
|---|
| 5950 | id="x1-101014r7"></a><span
|
|---|
| 5951 | class="cmr-6">7</span><br class="fancyvrb" /><a
|
|---|
| 5952 | id="x1-101016r8"></a><span
|
|---|
| 5953 | class="cmr-6">8</span><span
|
|---|
| 5954 | class="cmtt-8"> </span><span
|
|---|
| 5955 | class="cmtt-8"> </span><span
|
|---|
| 5956 | class="cmtt-8"> </span><span
|
|---|
| 5957 | class="cmtt-8"> </span><span
|
|---|
| 5958 | class="cmtt-8"> </span><span
|
|---|
| 5959 | class="cmsy-8">}</span><br class="fancyvrb" /><a
|
|---|
| 5960 | id="x1-101018r9"></a><span
|
|---|
| 5961 | class="cmr-6">9</span>
|
|---|
| 5962 | <br class="fancyvrb" /><a
|
|---|
| 5963 | id="x1-101020r10"></a><span
|
|---|
| 5964 | class="cmr-6">10</span><span
|
|---|
| 5965 | class="cmtt-8"> </span><span
|
|---|
| 5966 | class="cmtt-8"> 5)</span><span
|
|---|
| 5967 | class="cmtt-8"> [maximum</span><span
|
|---|
| 5968 | class="cmtt-8">_class]</span><span
|
|---|
| 5969 | class="cmtt-8"> =</span><span
|
|---|
| 5970 | class="cmtt-8"> largest</span><span
|
|---|
| 5971 | class="cmtt-8"> integer</span><span
|
|---|
| 5972 | class="cmtt-8"> scalar</span><span
|
|---|
| 5973 | class="cmtt-8"> value</span><span
|
|---|
| 5974 | class="cmtt-8"> in</span><span
|
|---|
| 5975 | class="cmtt-8"> vector</span><span
|
|---|
| 5976 | class="cmtt-8"> [floor1</span><span
|
|---|
| 5977 | class="cmtt-8">_partition</span><span
|
|---|
| 5978 | class="cmtt-8">_class</span><span
|
|---|
| 5979 | class="cmtt-8">_list]</span><br class="fancyvrb" /><a
|
|---|
| 5980 | id="x1-101022r11"></a><span
|
|---|
| 5981 | class="cmr-6">11</span><span
|
|---|
| 5982 | class="cmtt-8"> </span><span
|
|---|
| 5983 | class="cmtt-8"> 6)</span><span
|
|---|
| 5984 | class="cmtt-8"> iterate</span><span
|
|---|
| 5985 | class="cmtt-8"> [i]</span><span
|
|---|
| 5986 | class="cmtt-8"> over</span><span
|
|---|
| 5987 | class="cmtt-8"> the</span><span
|
|---|
| 5988 | class="cmtt-8"> range</span><span
|
|---|
| 5989 | class="cmtt-8"> 0</span><span
|
|---|
| 5990 | class="cmtt-8"> ...</span><span
|
|---|
| 5991 | class="cmtt-8"> [maximum</span><span
|
|---|
| 5992 | class="cmtt-8">_class]</span><span
|
|---|
| 5993 | class="cmtt-8"> </span><span
|
|---|
| 5994 | class="cmsy-8">{</span><br class="fancyvrb" /><a
|
|---|
| 5995 | id="x1-101024r12"></a><span
|
|---|
| 5996 | class="cmr-6">12</span>
|
|---|
| 5997 | <br class="fancyvrb" /><a
|
|---|
| 5998 | id="x1-101026r13"></a><span
|
|---|
| 5999 | class="cmr-6">13</span><span
|
|---|
| 6000 | class="cmtt-8"> </span><span
|
|---|
| 6001 | class="cmtt-8"> </span><span
|
|---|
| 6002 | class="cmtt-8"> </span><span
|
|---|
| 6003 | class="cmtt-8"> </span><span
|
|---|
| 6004 | class="cmtt-8"> </span><span
|
|---|
| 6005 | class="cmtt-8"> </span><span
|
|---|
| 6006 | class="cmtt-8"> </span><span
|
|---|
| 6007 | class="cmtt-8"> 7)</span><span
|
|---|
| 6008 | class="cmtt-8"> vector</span><span
|
|---|
| 6009 | class="cmtt-8"> [floor1</span><span
|
|---|
| 6010 | class="cmtt-8">_class</span><span
|
|---|
| 6011 | class="cmtt-8">_dimensions]</span><span
|
|---|
| 6012 | class="cmtt-8"> element</span><span
|
|---|
| 6013 | class="cmtt-8"> [i]</span><span
|
|---|
| 6014 | class="cmtt-8"> =</span><span
|
|---|
| 6015 | class="cmtt-8"> read</span><span
|
|---|
| 6016 | class="cmtt-8"> 3</span><span
|
|---|
| 6017 | class="cmtt-8"> bits</span><span
|
|---|
| 6018 | class="cmtt-8"> as</span><span
|
|---|
| 6019 | class="cmtt-8"> unsigned</span><span
|
|---|
| 6020 | class="cmtt-8"> integer</span><span
|
|---|
| 6021 | class="cmtt-8"> and</span><span
|
|---|
| 6022 | class="cmtt-8"> add</span><span
|
|---|
| 6023 | class="cmtt-8"> 1</span>
|
|---|
| 6024 | <br class="fancyvrb" /><a
|
|---|
| 6025 | id="x1-101028r14"></a><span
|
|---|
| 6026 | class="cmr-6">14</span> <span
|
|---|
| 6027 | class="cmtt-8">8)</span><span
|
|---|
| 6028 | class="cmtt-8"> vector</span><span
|
|---|
| 6029 | class="cmtt-8"> [floor1</span><span
|
|---|
| 6030 | class="cmtt-8">_class</span><span
|
|---|
| 6031 | class="cmtt-8">_subclasses]</span><span
|
|---|
| 6032 | class="cmtt-8"> element</span><span
|
|---|
| 6033 | class="cmtt-8"> [i]</span><span
|
|---|
| 6034 | class="cmtt-8"> =</span><span
|
|---|
| 6035 | class="cmtt-8"> read</span><span
|
|---|
| 6036 | class="cmtt-8"> 2</span><span
|
|---|
| 6037 | class="cmtt-8"> bits</span><span
|
|---|
| 6038 | class="cmtt-8"> as</span><span
|
|---|
| 6039 | class="cmtt-8"> unsigned</span><span
|
|---|
| 6040 | class="cmtt-8"> integer</span>
|
|---|
| 6041 | <br class="fancyvrb" /><a
|
|---|
| 6042 | id="x1-101030r15"></a><span
|
|---|
| 6043 | class="cmr-6">15</span><span
|
|---|
| 6044 | class="cmtt-8"> </span><span
|
|---|
| 6045 | class="cmtt-8"> </span><span
|
|---|
| 6046 | class="cmtt-8"> </span><span
|
|---|
| 6047 | class="cmtt-8"> </span><span
|
|---|
| 6048 | class="cmtt-8"> </span><span
|
|---|
| 6049 | class="cmtt-8"> </span><span
|
|---|
| 6050 | class="cmtt-8"> </span><span
|
|---|
| 6051 | class="cmtt-8"> 9)</span><span
|
|---|
| 6052 | class="cmtt-8"> if</span><span
|
|---|
| 6053 | class="cmtt-8"> (</span><span
|
|---|
| 6054 | class="cmtt-8"> vector</span><span
|
|---|
| 6055 | class="cmtt-8"> [floor1</span><span
|
|---|
| 6056 | class="cmtt-8">_class</span><span
|
|---|
| 6057 | class="cmtt-8">_subclasses]</span><span
|
|---|
| 6058 | class="cmtt-8"> element</span><span
|
|---|
| 6059 | class="cmtt-8"> [i]</span><span
|
|---|
| 6060 | class="cmtt-8"> is</span><span
|
|---|
| 6061 | class="cmtt-8"> nonzero</span><span
|
|---|
| 6062 | class="cmtt-8"> )</span><span
|
|---|
| 6063 | class="cmtt-8"> </span><span
|
|---|
| 6064 | class="cmsy-8">{</span><br class="fancyvrb" /><a
|
|---|
| 6065 | id="x1-101032r16"></a><span
|
|---|
| 6066 | class="cmr-6">16</span>
|
|---|
| 6067 | <br class="fancyvrb" /><a
|
|---|
| 6068 | id="x1-101034r17"></a><span
|
|---|
| 6069 | class="cmr-6">17</span><span
|
|---|
| 6070 | class="cmtt-8"> </span><span
|
|---|
| 6071 | class="cmtt-8"> </span><span
|
|---|
| 6072 | class="cmtt-8"> </span><span
|
|---|
| 6073 | class="cmtt-8"> </span><span
|
|---|
| 6074 | class="cmtt-8"> </span><span
|
|---|
| 6075 | class="cmtt-8"> </span><span
|
|---|
| 6076 | class="cmtt-8"> </span><span
|
|---|
| 6077 | class="cmtt-8"> </span><span
|
|---|
| 6078 | class="cmtt-8"> </span><span
|
|---|
| 6079 | class="cmtt-8"> </span><span
|
|---|
| 6080 | class="cmtt-8"> </span><span
|
|---|
| 6081 | class="cmtt-8"> </span><span
|
|---|
| 6082 | class="cmtt-8"> 10)</span><span
|
|---|
| 6083 | class="cmtt-8"> vector</span><span
|
|---|
| 6084 | class="cmtt-8"> [floor1</span><span
|
|---|
| 6085 | class="cmtt-8">_class</span><span
|
|---|
| 6086 | class="cmtt-8">_masterbooks]</span><span
|
|---|
| 6087 | class="cmtt-8"> element</span><span
|
|---|
| 6088 | class="cmtt-8"> [i]</span><span
|
|---|
| 6089 | class="cmtt-8"> =</span><span
|
|---|
| 6090 | class="cmtt-8"> read</span><span
|
|---|
| 6091 | class="cmtt-8"> 8</span><span
|
|---|
| 6092 | class="cmtt-8"> bits</span><span
|
|---|
| 6093 | class="cmtt-8"> as</span><span
|
|---|
| 6094 | class="cmtt-8"> unsigned</span><span
|
|---|
| 6095 | class="cmtt-8"> integer</span><br class="fancyvrb" /><a
|
|---|
| 6096 | id="x1-101036r18"></a><span
|
|---|
| 6097 | class="cmr-6">18</span><br class="fancyvrb" /><a
|
|---|
| 6098 | id="x1-101038r19"></a><span
|
|---|
| 6099 | class="cmr-6">19</span><span
|
|---|
| 6100 | class="cmtt-8"> </span><span
|
|---|
| 6101 | class="cmtt-8"> </span><span
|
|---|
| 6102 | class="cmtt-8"> </span><span
|
|---|
| 6103 | class="cmtt-8"> </span><span
|
|---|
| 6104 | class="cmtt-8"> </span><span
|
|---|
| 6105 | class="cmtt-8"> </span><span
|
|---|
| 6106 | class="cmtt-8"> </span><span
|
|---|
| 6107 | class="cmtt-8"> </span><span
|
|---|
| 6108 | class="cmtt-8"> </span><span
|
|---|
| 6109 | class="cmtt-8"> </span><span
|
|---|
| 6110 | class="cmtt-8"> </span><span
|
|---|
| 6111 | class="cmsy-8">}</span><br class="fancyvrb" /><a
|
|---|
| 6112 | id="x1-101040r20"></a><span
|
|---|
| 6113 | class="cmr-6">20</span>
|
|---|
| 6114 | <br class="fancyvrb" /><a
|
|---|
| 6115 | id="x1-101042r21"></a><span
|
|---|
| 6116 | class="cmr-6">21</span><span
|
|---|
| 6117 | class="cmtt-8"> </span><span
|
|---|
| 6118 | class="cmtt-8"> </span><span
|
|---|
| 6119 | class="cmtt-8"> </span><span
|
|---|
| 6120 | class="cmtt-8"> </span><span
|
|---|
| 6121 | class="cmtt-8"> </span><span
|
|---|
| 6122 | class="cmtt-8"> </span><span
|
|---|
| 6123 | class="cmtt-8"> 11)</span><span
|
|---|
| 6124 | class="cmtt-8"> iterate</span><span
|
|---|
| 6125 | class="cmtt-8"> [j]</span><span
|
|---|
| 6126 | class="cmtt-8"> over</span><span
|
|---|
| 6127 | class="cmtt-8"> the</span><span
|
|---|
| 6128 | class="cmtt-8"> range</span><span
|
|---|
| 6129 | class="cmtt-8"> 0</span><span
|
|---|
| 6130 | class="cmtt-8"> ...</span><span
|
|---|
| 6131 | class="cmtt-8"> (2</span><span
|
|---|
| 6132 | class="cmtt-8"> exponent</span><span
|
|---|
| 6133 | class="cmtt-8"> [floor1</span><span
|
|---|
| 6134 | class="cmtt-8">_class</span><span
|
|---|
| 6135 | class="cmtt-8">_subclasses]</span><span
|
|---|
| 6136 | class="cmtt-8"> element</span><span
|
|---|
| 6137 | class="cmtt-8"> [i])</span><span
|
|---|
| 6138 | class="cmtt-8"> -</span><span
|
|---|
| 6139 | class="cmtt-8"> 1</span><span
|
|---|
| 6140 | class="cmtt-8"> </span><span
|
|---|
| 6141 | class="cmsy-8">{</span><br class="fancyvrb" /><a
|
|---|
| 6142 | id="x1-101044r22"></a><span
|
|---|
| 6143 | class="cmr-6">22</span>
|
|---|
| 6144 | <br class="fancyvrb" /><a
|
|---|
| 6145 | id="x1-101046r23"></a><span
|
|---|
| 6146 | class="cmr-6">23</span><span
|
|---|
| 6147 | class="cmtt-8"> </span><span
|
|---|
| 6148 | class="cmtt-8"> </span><span
|
|---|
| 6149 | class="cmtt-8"> </span><span
|
|---|
| 6150 | class="cmtt-8"> </span><span
|
|---|
| 6151 | class="cmtt-8"> </span><span
|
|---|
| 6152 | class="cmtt-8"> </span><span
|
|---|
| 6153 | class="cmtt-8"> </span><span
|
|---|
| 6154 | class="cmtt-8"> </span><span
|
|---|
| 6155 | class="cmtt-8"> </span><span
|
|---|
| 6156 | class="cmtt-8"> </span><span
|
|---|
| 6157 | class="cmtt-8"> </span><span
|
|---|
| 6158 | class="cmtt-8"> </span><span
|
|---|
| 6159 | class="cmtt-8"> 12)</span><span
|
|---|
| 6160 | class="cmtt-8"> array</span><span
|
|---|
| 6161 | class="cmtt-8"> [floor1</span><span
|
|---|
| 6162 | class="cmtt-8">_subclass</span><span
|
|---|
| 6163 | class="cmtt-8">_books]</span><span
|
|---|
| 6164 | class="cmtt-8"> element</span><span
|
|---|
| 6165 | class="cmtt-8"> [i],[j]</span><span
|
|---|
| 6166 | class="cmtt-8"> =</span><br class="fancyvrb" /><a
|
|---|
| 6167 | id="x1-101048r24"></a><span
|
|---|
| 6168 | class="cmr-6">24</span><span
|
|---|
| 6169 | class="cmtt-8"> </span><span
|
|---|
| 6170 | class="cmtt-8"> </span><span
|
|---|
| 6171 | class="cmtt-8"> </span><span
|
|---|
| 6172 | class="cmtt-8"> </span><span
|
|---|
| 6173 | class="cmtt-8"> </span><span
|
|---|
| 6174 | class="cmtt-8"> </span><span
|
|---|
| 6175 | class="cmtt-8"> </span><span
|
|---|
| 6176 | class="cmtt-8"> </span><span
|
|---|
| 6177 | class="cmtt-8"> </span><span
|
|---|
| 6178 | class="cmtt-8"> </span><span
|
|---|
| 6179 | class="cmtt-8"> </span><span
|
|---|
| 6180 | class="cmtt-8"> </span><span
|
|---|
| 6181 | class="cmtt-8"> </span><span
|
|---|
| 6182 | class="cmtt-8"> </span><span
|
|---|
| 6183 | class="cmtt-8"> </span><span
|
|---|
| 6184 | class="cmtt-8"> </span><span
|
|---|
| 6185 | class="cmtt-8"> read</span><span
|
|---|
| 6186 | class="cmtt-8"> 8</span><span
|
|---|
| 6187 | class="cmtt-8"> bits</span><span
|
|---|
| 6188 | class="cmtt-8"> as</span><span
|
|---|
| 6189 | class="cmtt-8"> unsigned</span><span
|
|---|
| 6190 | class="cmtt-8"> integer</span><span
|
|---|
| 6191 | class="cmtt-8"> and</span><span
|
|---|
| 6192 | class="cmtt-8"> subtract</span><span
|
|---|
| 6193 | class="cmtt-8"> one</span>
|
|---|
| 6194 | <br class="fancyvrb" /><a
|
|---|
| 6195 | id="x1-101050r25"></a><span
|
|---|
| 6196 | class="cmr-6">25</span><span
|
|---|
| 6197 | class="cmtt-8"> </span><span
|
|---|
| 6198 | class="cmtt-8"> </span><span
|
|---|
| 6199 | class="cmtt-8"> </span><span
|
|---|
| 6200 | class="cmtt-8"> </span><span
|
|---|
| 6201 | class="cmtt-8"> </span><span
|
|---|
| 6202 | class="cmtt-8"> </span><span
|
|---|
| 6203 | class="cmtt-8"> </span><span
|
|---|
| 6204 | class="cmtt-8"> </span><span
|
|---|
| 6205 | class="cmtt-8"> </span><span
|
|---|
| 6206 | class="cmtt-8"> </span><span
|
|---|
| 6207 | class="cmtt-8"> </span><span
|
|---|
| 6208 | class="cmsy-8">}</span><br class="fancyvrb" /><a
|
|---|
| 6209 | id="x1-101052r26"></a><span
|
|---|
| 6210 | class="cmr-6">26</span><span
|
|---|
| 6211 | class="cmtt-8"> </span><span
|
|---|
| 6212 | class="cmtt-8"> </span><span
|
|---|
| 6213 | class="cmtt-8"> </span><span
|
|---|
| 6214 | class="cmtt-8"> </span><span
|
|---|
| 6215 | class="cmtt-8"> </span><span
|
|---|
| 6216 | class="cmtt-8"> </span><span
|
|---|
| 6217 | class="cmsy-8">}</span><br class="fancyvrb" /><a
|
|---|
| 6218 | id="x1-101054r27"></a><span
|
|---|
| 6219 | class="cmr-6">27</span><br class="fancyvrb" /><a
|
|---|
| 6220 | id="x1-101056r28"></a><span
|
|---|
| 6221 | class="cmr-6">28</span><span
|
|---|
| 6222 | class="cmtt-8"> 13)</span><span
|
|---|
| 6223 | class="cmtt-8"> [floor1</span><span
|
|---|
| 6224 | class="cmtt-8">_multiplier]</span><span
|
|---|
| 6225 | class="cmtt-8"> =</span><span
|
|---|
| 6226 | class="cmtt-8"> read</span><span
|
|---|
| 6227 | class="cmtt-8"> 2</span><span
|
|---|
| 6228 | class="cmtt-8"> bits</span><span
|
|---|
| 6229 | class="cmtt-8"> as</span><span
|
|---|
| 6230 | class="cmtt-8"> unsigned</span><span
|
|---|
| 6231 | class="cmtt-8"> integer</span><span
|
|---|
| 6232 | class="cmtt-8"> and</span><span
|
|---|
| 6233 | class="cmtt-8"> add</span><span
|
|---|
| 6234 | class="cmtt-8"> one</span><br class="fancyvrb" /><a
|
|---|
| 6235 | id="x1-101058r29"></a><span
|
|---|
| 6236 | class="cmr-6">29</span><span
|
|---|
| 6237 | class="cmtt-8"> 14)</span><span
|
|---|
| 6238 | class="cmtt-8"> [rangebits]</span><span
|
|---|
| 6239 | class="cmtt-8"> =</span><span
|
|---|
| 6240 | class="cmtt-8"> read</span><span
|
|---|
| 6241 | class="cmtt-8"> 4</span><span
|
|---|
| 6242 | class="cmtt-8"> bits</span><span
|
|---|
| 6243 | class="cmtt-8"> as</span><span
|
|---|
| 6244 | class="cmtt-8"> unsigned</span><span
|
|---|
| 6245 | class="cmtt-8"> integer</span>
|
|---|
| 6246 | <br class="fancyvrb" /><a
|
|---|
| 6247 | id="x1-101060r30"></a><span
|
|---|
| 6248 | class="cmr-6">30</span><span
|
|---|
| 6249 | class="cmtt-8"> 15)</span><span
|
|---|
| 6250 | class="cmtt-8"> vector</span><span
|
|---|
| 6251 | class="cmtt-8"> [floor1</span><span
|
|---|
| 6252 | class="cmtt-8">_X</span><span
|
|---|
| 6253 | class="cmtt-8">_list]</span><span
|
|---|
| 6254 | class="cmtt-8"> element</span><span
|
|---|
| 6255 | class="cmtt-8"> [0]</span><span
|
|---|
| 6256 | class="cmtt-8"> =</span><span
|
|---|
| 6257 | class="cmtt-8"> 0</span><br class="fancyvrb" /><a
|
|---|
| 6258 | id="x1-101062r31"></a><span
|
|---|
| 6259 | class="cmr-6">31</span><span
|
|---|
| 6260 | class="cmtt-8"> 16)</span><span
|
|---|
| 6261 | class="cmtt-8"> vector</span><span
|
|---|
| 6262 | class="cmtt-8"> [floor1</span><span
|
|---|
| 6263 | class="cmtt-8">_X</span><span
|
|---|
| 6264 | class="cmtt-8">_list]</span><span
|
|---|
| 6265 | class="cmtt-8"> element</span><span
|
|---|
| 6266 | class="cmtt-8"> [1]</span><span
|
|---|
| 6267 | class="cmtt-8"> =</span><span
|
|---|
| 6268 | class="cmtt-8"> 2</span><span
|
|---|
| 6269 | class="cmtt-8"> exponent</span><span
|
|---|
| 6270 | class="cmtt-8"> [rangebits];</span><br class="fancyvrb" /><a
|
|---|
| 6271 | id="x1-101064r32"></a><span
|
|---|
| 6272 | class="cmr-6">32</span><span
|
|---|
| 6273 | class="cmtt-8"> 17)</span><span
|
|---|
| 6274 | class="cmtt-8"> [floor1</span><span
|
|---|
| 6275 | class="cmtt-8">_values]</span><span
|
|---|
| 6276 | class="cmtt-8"> =</span><span
|
|---|
| 6277 | class="cmtt-8"> 2</span>
|
|---|
| 6278 | <br class="fancyvrb" /><a
|
|---|
| 6279 | id="x1-101066r33"></a><span
|
|---|
| 6280 | class="cmr-6">33</span><span
|
|---|
| 6281 | class="cmtt-8"> 18)</span><span
|
|---|
| 6282 | class="cmtt-8"> iterate</span><span
|
|---|
| 6283 | class="cmtt-8"> [i]</span><span
|
|---|
| 6284 | class="cmtt-8"> over</span><span
|
|---|
| 6285 | class="cmtt-8"> the</span><span
|
|---|
| 6286 | class="cmtt-8"> range</span><span
|
|---|
| 6287 | class="cmtt-8"> 0</span><span
|
|---|
| 6288 | class="cmtt-8"> ...</span><span
|
|---|
| 6289 | class="cmtt-8"> [floor1</span><span
|
|---|
| 6290 | class="cmtt-8">_partitions]-1</span><span
|
|---|
| 6291 | class="cmtt-8"> </span><span
|
|---|
| 6292 | class="cmsy-8">{</span><br class="fancyvrb" /><a
|
|---|
| 6293 | id="x1-101068r34"></a><span
|
|---|
| 6294 | class="cmr-6">34</span><br class="fancyvrb" /><a
|
|---|
| 6295 | id="x1-101070r35"></a><span
|
|---|
| 6296 | class="cmr-6">35</span><span
|
|---|
| 6297 | class="cmtt-8"> </span><span
|
|---|
| 6298 | class="cmtt-8"> </span><span
|
|---|
| 6299 | class="cmtt-8"> </span><span
|
|---|
| 6300 | class="cmtt-8"> </span><span
|
|---|
| 6301 | class="cmtt-8"> </span><span
|
|---|
| 6302 | class="cmtt-8"> </span><span
|
|---|
| 6303 | class="cmtt-8"> 19)</span><span
|
|---|
| 6304 | class="cmtt-8"> [current</span><span
|
|---|
| 6305 | class="cmtt-8">_class</span><span
|
|---|
| 6306 | class="cmtt-8">_number]</span><span
|
|---|
| 6307 | class="cmtt-8"> =</span><span
|
|---|
| 6308 | class="cmtt-8"> vector</span><span
|
|---|
| 6309 | class="cmtt-8"> [floor1</span><span
|
|---|
| 6310 | class="cmtt-8">_partition</span><span
|
|---|
| 6311 | class="cmtt-8">_class</span><span
|
|---|
| 6312 | class="cmtt-8">_list]</span><span
|
|---|
| 6313 | class="cmtt-8"> element</span><span
|
|---|
| 6314 | class="cmtt-8"> [i]</span>
|
|---|
| 6315 | <br class="fancyvrb" /><a
|
|---|
| 6316 | id="x1-101072r36"></a><span
|
|---|
| 6317 | class="cmr-6">36</span><span
|
|---|
| 6318 | class="cmtt-8"> </span><span
|
|---|
| 6319 | class="cmtt-8"> </span><span
|
|---|
| 6320 | class="cmtt-8"> </span><span
|
|---|
| 6321 | class="cmtt-8"> </span><span
|
|---|
| 6322 | class="cmtt-8"> </span><span
|
|---|
| 6323 | class="cmtt-8"> </span><span
|
|---|
| 6324 | class="cmtt-8"> 20)</span><span
|
|---|
| 6325 | class="cmtt-8"> iterate</span><span
|
|---|
| 6326 | class="cmtt-8"> [j]</span><span
|
|---|
| 6327 | class="cmtt-8"> over</span><span
|
|---|
| 6328 | class="cmtt-8"> the</span><span
|
|---|
| 6329 | class="cmtt-8"> range</span><span
|
|---|
| 6330 | class="cmtt-8"> 0</span><span
|
|---|
| 6331 | class="cmtt-8"> ...</span><span
|
|---|
| 6332 | class="cmtt-8"> ([floor1</span><span
|
|---|
| 6333 | class="cmtt-8">_class</span><span
|
|---|
| 6334 | class="cmtt-8">_dimensions]</span><span
|
|---|
| 6335 | class="cmtt-8"> element</span><span
|
|---|
| 6336 | class="cmtt-8"> [current</span><span
|
|---|
| 6337 | class="cmtt-8">_class</span><span
|
|---|
| 6338 | class="cmtt-8">_number])-1</span><span
|
|---|
| 6339 | class="cmtt-8"> </span><span
|
|---|
| 6340 | class="cmsy-8">{</span>
|
|---|
| 6341 | <br class="fancyvrb" /><a
|
|---|
| 6342 | id="x1-101074r37"></a><span
|
|---|
| 6343 | class="cmr-6">37</span><span
|
|---|
| 6344 | class="cmtt-8"> </span><span
|
|---|
| 6345 | class="cmtt-8"> </span><span
|
|---|
| 6346 | class="cmtt-8"> </span><span
|
|---|
| 6347 | class="cmtt-8"> </span><span
|
|---|
| 6348 | class="cmtt-8"> </span><span
|
|---|
| 6349 | class="cmtt-8"> </span><span
|
|---|
| 6350 | class="cmtt-8"> </span><span
|
|---|
| 6351 | class="cmtt-8"> </span><span
|
|---|
| 6352 | class="cmtt-8"> </span><span
|
|---|
| 6353 | class="cmtt-8"> </span><span
|
|---|
| 6354 | class="cmtt-8"> </span><span
|
|---|
| 6355 | class="cmtt-8"> </span><span
|
|---|
| 6356 | class="cmtt-8"> 21)</span><span
|
|---|
| 6357 | class="cmtt-8"> vector</span><span
|
|---|
| 6358 | class="cmtt-8"> [floor1</span><span
|
|---|
| 6359 | class="cmtt-8">_X</span><span
|
|---|
| 6360 | class="cmtt-8">_list]</span><span
|
|---|
| 6361 | class="cmtt-8"> element</span><span
|
|---|
| 6362 | class="cmtt-8"> ([floor1</span><span
|
|---|
| 6363 | class="cmtt-8">_values])</span><span
|
|---|
| 6364 | class="cmtt-8"> =</span><br class="fancyvrb" /><a
|
|---|
| 6365 | id="x1-101076r38"></a><span
|
|---|
| 6366 | class="cmr-6">38</span><span
|
|---|
| 6367 | class="cmtt-8"> </span><span
|
|---|
| 6368 | class="cmtt-8"> </span><span
|
|---|
| 6369 | class="cmtt-8"> </span><span
|
|---|
| 6370 | class="cmtt-8"> </span><span
|
|---|
| 6371 | class="cmtt-8"> </span><span
|
|---|
| 6372 | class="cmtt-8"> </span><span
|
|---|
| 6373 | class="cmtt-8"> </span><span
|
|---|
| 6374 | class="cmtt-8"> </span><span
|
|---|
| 6375 | class="cmtt-8"> </span><span
|
|---|
| 6376 | class="cmtt-8"> </span><span
|
|---|
| 6377 | class="cmtt-8"> </span><span
|
|---|
| 6378 | class="cmtt-8"> </span><span
|
|---|
| 6379 | class="cmtt-8"> </span><span
|
|---|
| 6380 | class="cmtt-8"> </span><span
|
|---|
| 6381 | class="cmtt-8"> </span><span
|
|---|
| 6382 | class="cmtt-8"> </span><span
|
|---|
| 6383 | class="cmtt-8"> read</span><span
|
|---|
| 6384 | class="cmtt-8"> [rangebits]</span><span
|
|---|
| 6385 | class="cmtt-8"> bits</span><span
|
|---|
| 6386 | class="cmtt-8"> as</span><span
|
|---|
| 6387 | class="cmtt-8"> unsigned</span><span
|
|---|
| 6388 | class="cmtt-8"> integer</span>
|
|---|
| 6389 | <br class="fancyvrb" /><a
|
|---|
| 6390 | id="x1-101078r39"></a><span
|
|---|
| 6391 | class="cmr-6">39</span><span
|
|---|
| 6392 | class="cmtt-8"> </span><span
|
|---|
| 6393 | class="cmtt-8"> </span><span
|
|---|
| 6394 | class="cmtt-8"> </span><span
|
|---|
| 6395 | class="cmtt-8"> </span><span
|
|---|
| 6396 | class="cmtt-8"> </span><span
|
|---|
| 6397 | class="cmtt-8"> </span><span
|
|---|
| 6398 | class="cmtt-8"> </span><span
|
|---|
| 6399 | class="cmtt-8"> </span><span
|
|---|
| 6400 | class="cmtt-8"> </span><span
|
|---|
| 6401 | class="cmtt-8"> </span><span
|
|---|
| 6402 | class="cmtt-8"> </span><span
|
|---|
| 6403 | class="cmtt-8"> </span><span
|
|---|
| 6404 | class="cmtt-8"> 22)</span><span
|
|---|
| 6405 | class="cmtt-8"> increment</span><span
|
|---|
| 6406 | class="cmtt-8"> [floor1</span><span
|
|---|
| 6407 | class="cmtt-8">_values]</span><span
|
|---|
| 6408 | class="cmtt-8"> by</span><span
|
|---|
| 6409 | class="cmtt-8"> one</span><br class="fancyvrb" /><a
|
|---|
| 6410 | id="x1-101080r40"></a><span
|
|---|
| 6411 | class="cmr-6">40</span><span
|
|---|
| 6412 | class="cmtt-8"> </span><span
|
|---|
| 6413 | class="cmtt-8"> </span><span
|
|---|
| 6414 | class="cmtt-8"> </span><span
|
|---|
| 6415 | class="cmtt-8"> </span><span
|
|---|
| 6416 | class="cmtt-8"> </span><span
|
|---|
| 6417 | class="cmtt-8"> </span><span
|
|---|
| 6418 | class="cmtt-8"> </span><span
|
|---|
| 6419 | class="cmtt-8"> </span><span
|
|---|
| 6420 | class="cmtt-8"> </span><span
|
|---|
| 6421 | class="cmtt-8"> </span><span
|
|---|
| 6422 | class="cmtt-8"> </span><span
|
|---|
| 6423 | class="cmsy-8">}</span><br class="fancyvrb" /><a
|
|---|
| 6424 | id="x1-101082r41"></a><span
|
|---|
| 6425 | class="cmr-6">41</span><span
|
|---|
| 6426 | class="cmtt-8"> </span><span
|
|---|
| 6427 | class="cmtt-8"> </span><span
|
|---|
| 6428 | class="cmtt-8"> </span><span
|
|---|
| 6429 | class="cmtt-8"> </span><span
|
|---|
| 6430 | class="cmtt-8"> </span><span
|
|---|
| 6431 | class="cmsy-8">}</span><br class="fancyvrb" /><a
|
|---|
| 6432 | id="x1-101084r42"></a><span
|
|---|
| 6433 | class="cmr-6">42</span><br class="fancyvrb" /><a
|
|---|
| 6434 | id="x1-101086r43"></a><span
|
|---|
| 6435 | class="cmr-6">43</span><span
|
|---|
| 6436 | class="cmtt-8"> 23)</span><span
|
|---|
| 6437 | class="cmtt-8"> done</span></div>
|
|---|
| 6438 | <!--l. 157--><p class="noindent" >An end-of-packet condition while reading any aspect of a floor 1 configuration during
|
|---|
| 6439 | setup renders a stream undecodable. In addition, a <span
|
|---|
| 6440 | class="cmtt-12">[floor1</span><span
|
|---|
| 6441 | class="cmtt-12">_class</span><span
|
|---|
| 6442 | class="cmtt-12">_masterbooks] </span>or
|
|---|
| 6443 | <span
|
|---|
| 6444 | class="cmtt-12">[floor1</span><span
|
|---|
| 6445 | class="cmtt-12">_subclass</span><span
|
|---|
| 6446 | class="cmtt-12">_books] </span>scalar element greater than the highest numbered codebook
|
|---|
| 6447 | configured in this stream is an error condition that renders the stream undecodable. Vector
|
|---|
| 6448 | [floor1_x_list] is limited to a maximum length of 65 elements; a setup indicating more than 65
|
|---|
| 6449 | total elements (including elements 0 and 1 set prior to the read loop) renders the stream
|
|---|
| 6450 | undecodable. All vector [floor1_x_list] element values must be unique within the vector; a
|
|---|
| 6451 | non-unique value renders the stream undecodable.
|
|---|
| 6452 | <!--l. 169--><p class="noindent" >
|
|---|
| 6453 | <h5 class="subsubsectionHead"><span class="titlemark">7.2.3. </span> <a
|
|---|
| 6454 | id="x1-1020007.2.3"></a>packet decode</h5>
|
|---|
| 6455 | <!--l. 171--><p class="noindent" >Packet decode begins by checking the <span
|
|---|
| 6456 | class="cmtt-12">[nonzero] </span>flag:
|
|---|
| 6457 | <!--l. 173--><p class="noindent" >
|
|---|
| 6458 | <div class="fancyvrb" id="fancyvrb29"><a
|
|---|
| 6459 | id="x1-102002r1"></a><span
|
|---|
| 6460 | class="cmr-6">1</span><span
|
|---|
| 6461 | class="cmtt-8"> </span><span
|
|---|
| 6462 | class="cmtt-8"> 1)</span><span
|
|---|
| 6463 | class="cmtt-8"> [nonzero]</span><span
|
|---|
| 6464 | class="cmtt-8"> =</span><span
|
|---|
| 6465 | class="cmtt-8"> read</span><span
|
|---|
| 6466 | class="cmtt-8"> 1</span><span
|
|---|
| 6467 | class="cmtt-8"> bit</span><span
|
|---|
| 6468 | class="cmtt-8"> as</span><span
|
|---|
| 6469 | class="cmtt-8"> boolean</span></div>
|
|---|
| 6470 | <!--l. 177--><p class="noindent" >If <span
|
|---|
| 6471 | class="cmtt-12">[nonzero] </span>is unset, that indicates this channel contained no audio energy in this frame.
|
|---|
| 6472 | Decode immediately returns a status indicating this floor curve (and thus this channel) is unused
|
|---|
| 6473 | this frame. (A return status of ’unused’ is different from decoding a floor that has all
|
|---|
| 6474 | points set to minimum representation amplitude, which happens to be approximately
|
|---|
| 6475 | -140dB).
|
|---|
| 6476 | <!--l. 185--><p class="noindent" >Assuming <span
|
|---|
| 6477 | class="cmtt-12">[nonzero] </span>is set, decode proceeds as follows:
|
|---|
| 6478 | <!--l. 187--><p class="noindent" >
|
|---|
| 6479 | <div class="fancyvrb" id="fancyvrb30"><a
|
|---|
| 6480 | id="x1-102004r1"></a><span
|
|---|
| 6481 | class="cmr-6">1</span><span
|
|---|
| 6482 | class="cmtt-8"> </span><span
|
|---|
| 6483 | class="cmtt-8"> 1)</span><span
|
|---|
| 6484 | class="cmtt-8"> [range]</span><span
|
|---|
| 6485 | class="cmtt-8"> =</span><span
|
|---|
| 6486 | class="cmtt-8"> vector</span><span
|
|---|
| 6487 | class="cmtt-8"> </span><span
|
|---|
| 6488 | class="cmsy-8">{</span><span
|
|---|
| 6489 | class="cmtt-8"> 256,</span><span
|
|---|
| 6490 | class="cmtt-8"> 128,</span><span
|
|---|
| 6491 | class="cmtt-8"> 86,</span><span
|
|---|
| 6492 | class="cmtt-8"> 64</span><span
|
|---|
| 6493 | class="cmtt-8"> </span><span
|
|---|
| 6494 | class="cmsy-8">}</span><span
|
|---|
| 6495 | class="cmtt-8"> element</span><span
|
|---|
| 6496 | class="cmtt-8"> ([floor1</span><span
|
|---|
| 6497 | class="cmtt-8">_multiplier]-1)</span>
|
|---|
| 6498 | <br class="fancyvrb" /><a
|
|---|
| 6499 | id="x1-102006r2"></a><span
|
|---|
| 6500 | class="cmr-6">2</span><span
|
|---|
| 6501 | class="cmtt-8"> </span><span
|
|---|
| 6502 | class="cmtt-8"> 2)</span><span
|
|---|
| 6503 | class="cmtt-8"> vector</span><span
|
|---|
| 6504 | class="cmtt-8"> [floor1</span><span
|
|---|
| 6505 | class="cmtt-8">_Y]</span><span
|
|---|
| 6506 | class="cmtt-8"> element</span><span
|
|---|
| 6507 | class="cmtt-8"> [0]</span><span
|
|---|
| 6508 | class="cmtt-8"> =</span><span
|
|---|
| 6509 | class="cmtt-8"> read</span><span
|
|---|
| 6510 | class="cmtt-8"> </span><a
|
|---|
| 6511 | href="#x1-1190009.2.1"><span
|
|---|
| 6512 | class="cmtt-8">ilog</span></a><span
|
|---|
| 6513 | class="cmtt-8">([range]-1)</span><span
|
|---|
| 6514 | class="cmtt-8"> bits</span><span
|
|---|
| 6515 | class="cmtt-8"> as</span><span
|
|---|
| 6516 | class="cmtt-8"> unsigned</span><span
|
|---|
| 6517 | class="cmtt-8"> integer</span>
|
|---|
| 6518 |
|
|---|
| 6519 |
|
|---|
| 6520 |
|
|---|
| 6521 | <br class="fancyvrb" /><a
|
|---|
| 6522 | id="x1-102008r3"></a><span
|
|---|
| 6523 | class="cmr-6">3</span><span
|
|---|
| 6524 | class="cmtt-8"> </span><span
|
|---|
| 6525 | class="cmtt-8"> 3)</span><span
|
|---|
| 6526 | class="cmtt-8"> vector</span><span
|
|---|
| 6527 | class="cmtt-8"> [floor1</span><span
|
|---|
| 6528 | class="cmtt-8">_Y]</span><span
|
|---|
| 6529 | class="cmtt-8"> element</span><span
|
|---|
| 6530 | class="cmtt-8"> [1]</span><span
|
|---|
| 6531 | class="cmtt-8"> =</span><span
|
|---|
| 6532 | class="cmtt-8"> read</span><span
|
|---|
| 6533 | class="cmtt-8"> </span><a
|
|---|
| 6534 | href="#x1-1190009.2.1"><span
|
|---|
| 6535 | class="cmtt-8">ilog</span></a><span
|
|---|
| 6536 | class="cmtt-8">([range]-1)</span><span
|
|---|
| 6537 | class="cmtt-8"> bits</span><span
|
|---|
| 6538 | class="cmtt-8"> as</span><span
|
|---|
| 6539 | class="cmtt-8"> unsigned</span><span
|
|---|
| 6540 | class="cmtt-8"> integer</span>
|
|---|
| 6541 | <br class="fancyvrb" /><a
|
|---|
| 6542 | id="x1-102010r4"></a><span
|
|---|
| 6543 | class="cmr-6">4</span><span
|
|---|
| 6544 | class="cmtt-8"> </span><span
|
|---|
| 6545 | class="cmtt-8"> 4)</span><span
|
|---|
| 6546 | class="cmtt-8"> [offset]</span><span
|
|---|
| 6547 | class="cmtt-8"> =</span><span
|
|---|
| 6548 | class="cmtt-8"> 2;</span><br class="fancyvrb" /><a
|
|---|
| 6549 | id="x1-102012r5"></a><span
|
|---|
| 6550 | class="cmr-6">5</span><span
|
|---|
| 6551 | class="cmtt-8"> </span><span
|
|---|
| 6552 | class="cmtt-8"> 5)</span><span
|
|---|
| 6553 | class="cmtt-8"> iterate</span><span
|
|---|
| 6554 | class="cmtt-8"> [i]</span><span
|
|---|
| 6555 | class="cmtt-8"> over</span><span
|
|---|
| 6556 | class="cmtt-8"> the</span><span
|
|---|
| 6557 | class="cmtt-8"> range</span><span
|
|---|
| 6558 | class="cmtt-8"> 0</span><span
|
|---|
| 6559 | class="cmtt-8"> ...</span><span
|
|---|
| 6560 | class="cmtt-8"> [floor1</span><span
|
|---|
| 6561 | class="cmtt-8">_partitions]-1</span><span
|
|---|
| 6562 | class="cmtt-8"> </span><span
|
|---|
| 6563 | class="cmsy-8">{</span><br class="fancyvrb" /><a
|
|---|
| 6564 | id="x1-102014r6"></a><span
|
|---|
| 6565 | class="cmr-6">6</span>
|
|---|
| 6566 | <br class="fancyvrb" /><a
|
|---|
| 6567 | id="x1-102016r7"></a><span
|
|---|
| 6568 | class="cmr-6">7</span><span
|
|---|
| 6569 | class="cmtt-8"> </span><span
|
|---|
| 6570 | class="cmtt-8"> </span><span
|
|---|
| 6571 | class="cmtt-8"> </span><span
|
|---|
| 6572 | class="cmtt-8"> </span><span
|
|---|
| 6573 | class="cmtt-8"> </span><span
|
|---|
| 6574 | class="cmtt-8"> </span><span
|
|---|
| 6575 | class="cmtt-8"> 6)</span><span
|
|---|
| 6576 | class="cmtt-8"> [class]</span><span
|
|---|
| 6577 | class="cmtt-8"> =</span><span
|
|---|
| 6578 | class="cmtt-8"> vector</span><span
|
|---|
| 6579 | class="cmtt-8"> [floor1</span><span
|
|---|
| 6580 | class="cmtt-8">_partition</span><span
|
|---|
| 6581 | class="cmtt-8">_class]</span><span
|
|---|
| 6582 | class="cmtt-8"> </span><span
|
|---|
| 6583 | class="cmtt-8"> element</span><span
|
|---|
| 6584 | class="cmtt-8"> [i]</span><br class="fancyvrb" /><a
|
|---|
| 6585 | id="x1-102018r8"></a><span
|
|---|
| 6586 | class="cmr-6">8</span><span
|
|---|
| 6587 | class="cmtt-8"> </span><span
|
|---|
| 6588 | class="cmtt-8"> </span><span
|
|---|
| 6589 | class="cmtt-8"> </span><span
|
|---|
| 6590 | class="cmtt-8"> </span><span
|
|---|
| 6591 | class="cmtt-8"> </span><span
|
|---|
| 6592 | class="cmtt-8"> </span><span
|
|---|
| 6593 | class="cmtt-8"> 7)</span><span
|
|---|
| 6594 | class="cmtt-8"> [cdim]</span><span
|
|---|
| 6595 | class="cmtt-8"> </span><span
|
|---|
| 6596 | class="cmtt-8"> =</span><span
|
|---|
| 6597 | class="cmtt-8"> vector</span><span
|
|---|
| 6598 | class="cmtt-8"> [floor1</span><span
|
|---|
| 6599 | class="cmtt-8">_class</span><span
|
|---|
| 6600 | class="cmtt-8">_dimensions]</span><span
|
|---|
| 6601 | class="cmtt-8"> element</span><span
|
|---|
| 6602 | class="cmtt-8"> [class]</span>
|
|---|
| 6603 | <br class="fancyvrb" /><a
|
|---|
| 6604 | id="x1-102020r9"></a><span
|
|---|
| 6605 | class="cmr-6">9</span><span
|
|---|
| 6606 | class="cmtt-8"> </span><span
|
|---|
| 6607 | class="cmtt-8"> </span><span
|
|---|
| 6608 | class="cmtt-8"> </span><span
|
|---|
| 6609 | class="cmtt-8"> </span><span
|
|---|
| 6610 | class="cmtt-8"> </span><span
|
|---|
| 6611 | class="cmtt-8"> </span><span
|
|---|
| 6612 | class="cmtt-8"> 8)</span><span
|
|---|
| 6613 | class="cmtt-8"> [cbits]</span><span
|
|---|
| 6614 | class="cmtt-8"> =</span><span
|
|---|
| 6615 | class="cmtt-8"> vector</span><span
|
|---|
| 6616 | class="cmtt-8"> [floor1</span><span
|
|---|
| 6617 | class="cmtt-8">_class</span><span
|
|---|
| 6618 | class="cmtt-8">_subclasses]</span><span
|
|---|
| 6619 | class="cmtt-8"> element</span><span
|
|---|
| 6620 | class="cmtt-8"> [class]</span><br class="fancyvrb" /><a
|
|---|
| 6621 | id="x1-102022r10"></a><span
|
|---|
| 6622 | class="cmr-6">10</span><span
|
|---|
| 6623 | class="cmtt-8"> </span><span
|
|---|
| 6624 | class="cmtt-8"> </span><span
|
|---|
| 6625 | class="cmtt-8"> </span><span
|
|---|
| 6626 | class="cmtt-8"> </span><span
|
|---|
| 6627 | class="cmtt-8"> </span><span
|
|---|
| 6628 | class="cmtt-8"> </span><span
|
|---|
| 6629 | class="cmtt-8"> 9)</span><span
|
|---|
| 6630 | class="cmtt-8"> [csub]</span><span
|
|---|
| 6631 | class="cmtt-8"> </span><span
|
|---|
| 6632 | class="cmtt-8"> =</span><span
|
|---|
| 6633 | class="cmtt-8"> (2</span><span
|
|---|
| 6634 | class="cmtt-8"> exponent</span><span
|
|---|
| 6635 | class="cmtt-8"> [cbits])-1</span><br class="fancyvrb" /><a
|
|---|
| 6636 | id="x1-102024r11"></a><span
|
|---|
| 6637 | class="cmr-6">11</span><span
|
|---|
| 6638 | class="cmtt-8"> </span><span
|
|---|
| 6639 | class="cmtt-8"> </span><span
|
|---|
| 6640 | class="cmtt-8"> </span><span
|
|---|
| 6641 | class="cmtt-8"> </span><span
|
|---|
| 6642 | class="cmtt-8"> </span><span
|
|---|
| 6643 | class="cmtt-8"> 10)</span><span
|
|---|
| 6644 | class="cmtt-8"> [cval]</span><span
|
|---|
| 6645 | class="cmtt-8"> </span><span
|
|---|
| 6646 | class="cmtt-8"> =</span><span
|
|---|
| 6647 | class="cmtt-8"> 0</span>
|
|---|
| 6648 | <br class="fancyvrb" /><a
|
|---|
| 6649 | id="x1-102026r12"></a><span
|
|---|
| 6650 | class="cmr-6">12</span><span
|
|---|
| 6651 | class="cmtt-8"> </span><span
|
|---|
| 6652 | class="cmtt-8"> </span><span
|
|---|
| 6653 | class="cmtt-8"> </span><span
|
|---|
| 6654 | class="cmtt-8"> </span><span
|
|---|
| 6655 | class="cmtt-8"> </span><span
|
|---|
| 6656 | class="cmtt-8"> 11)</span><span
|
|---|
| 6657 | class="cmtt-8"> if</span><span
|
|---|
| 6658 | class="cmtt-8"> (</span><span
|
|---|
| 6659 | class="cmtt-8"> [cbits]</span><span
|
|---|
| 6660 | class="cmtt-8"> is</span><span
|
|---|
| 6661 | class="cmtt-8"> greater</span><span
|
|---|
| 6662 | class="cmtt-8"> than</span><span
|
|---|
| 6663 | class="cmtt-8"> zero</span><span
|
|---|
| 6664 | class="cmtt-8"> )</span><span
|
|---|
| 6665 | class="cmtt-8"> </span><span
|
|---|
| 6666 | class="cmsy-8">{</span><br class="fancyvrb" /><a
|
|---|
| 6667 | id="x1-102028r13"></a><span
|
|---|
| 6668 | class="cmr-6">13</span><br class="fancyvrb" /><a
|
|---|
| 6669 | id="x1-102030r14"></a><span
|
|---|
| 6670 | class="cmr-6">14</span><span
|
|---|
| 6671 | class="cmtt-8"> </span><span
|
|---|
| 6672 | class="cmtt-8"> </span><span
|
|---|
| 6673 | class="cmtt-8"> </span><span
|
|---|
| 6674 | class="cmtt-8"> </span><span
|
|---|
| 6675 | class="cmtt-8"> </span><span
|
|---|
| 6676 | class="cmtt-8"> </span><span
|
|---|
| 6677 | class="cmtt-8"> </span><span
|
|---|
| 6678 | class="cmtt-8"> </span><span
|
|---|
| 6679 | class="cmtt-8"> </span><span
|
|---|
| 6680 | class="cmtt-8"> </span><span
|
|---|
| 6681 | class="cmtt-8"> </span><span
|
|---|
| 6682 | class="cmtt-8"> </span><span
|
|---|
| 6683 | class="cmtt-8"> 12)</span><span
|
|---|
| 6684 | class="cmtt-8"> [cval]</span><span
|
|---|
| 6685 | class="cmtt-8"> =</span><span
|
|---|
| 6686 | class="cmtt-8"> read</span><span
|
|---|
| 6687 | class="cmtt-8"> from</span><span
|
|---|
| 6688 | class="cmtt-8"> packet</span><span
|
|---|
| 6689 | class="cmtt-8"> using</span><span
|
|---|
| 6690 | class="cmtt-8"> codebook</span><span
|
|---|
| 6691 | class="cmtt-8"> number</span>
|
|---|
| 6692 | <br class="fancyvrb" /><a
|
|---|
| 6693 | id="x1-102032r15"></a><span
|
|---|
| 6694 | class="cmr-6">15</span><span
|
|---|
| 6695 | class="cmtt-8"> </span><span
|
|---|
| 6696 | class="cmtt-8"> </span><span
|
|---|
| 6697 | class="cmtt-8"> </span><span
|
|---|
| 6698 | class="cmtt-8"> </span><span
|
|---|
| 6699 | class="cmtt-8"> </span><span
|
|---|
| 6700 | class="cmtt-8"> </span><span
|
|---|
| 6701 | class="cmtt-8"> </span><span
|
|---|
| 6702 | class="cmtt-8"> </span><span
|
|---|
| 6703 | class="cmtt-8"> </span><span
|
|---|
| 6704 | class="cmtt-8"> </span><span
|
|---|
| 6705 | class="cmtt-8"> </span><span
|
|---|
| 6706 | class="cmtt-8"> </span><span
|
|---|
| 6707 | class="cmtt-8"> </span><span
|
|---|
| 6708 | class="cmtt-8"> </span><span
|
|---|
| 6709 | class="cmtt-8"> </span><span
|
|---|
| 6710 | class="cmtt-8"> </span><span
|
|---|
| 6711 | class="cmtt-8"> (vector</span><span
|
|---|
| 6712 | class="cmtt-8"> [floor1</span><span
|
|---|
| 6713 | class="cmtt-8">_class</span><span
|
|---|
| 6714 | class="cmtt-8">_masterbooks]</span><span
|
|---|
| 6715 | class="cmtt-8"> element</span><span
|
|---|
| 6716 | class="cmtt-8"> [class])</span><span
|
|---|
| 6717 | class="cmtt-8"> in</span><span
|
|---|
| 6718 | class="cmtt-8"> scalar</span><span
|
|---|
| 6719 | class="cmtt-8"> context</span><br class="fancyvrb" /><a
|
|---|
| 6720 | id="x1-102034r16"></a><span
|
|---|
| 6721 | class="cmr-6">16</span><span
|
|---|
| 6722 | class="cmtt-8"> </span><span
|
|---|
| 6723 | class="cmtt-8"> </span><span
|
|---|
| 6724 | class="cmtt-8"> </span><span
|
|---|
| 6725 | class="cmtt-8"> </span><span
|
|---|
| 6726 | class="cmtt-8"> </span><span
|
|---|
| 6727 | class="cmtt-8"> </span><span
|
|---|
| 6728 | class="cmtt-8"> </span><span
|
|---|
| 6729 | class="cmtt-8"> </span><span
|
|---|
| 6730 | class="cmtt-8"> </span><span
|
|---|
| 6731 | class="cmtt-8"> </span><span
|
|---|
| 6732 | class="cmsy-8">}</span><br class="fancyvrb" /><a
|
|---|
| 6733 | id="x1-102036r17"></a><span
|
|---|
| 6734 | class="cmr-6">17</span><br class="fancyvrb" /><a
|
|---|
| 6735 | id="x1-102038r18"></a><span
|
|---|
| 6736 | class="cmr-6">18</span><span
|
|---|
| 6737 | class="cmtt-8"> </span><span
|
|---|
| 6738 | class="cmtt-8"> </span><span
|
|---|
| 6739 | class="cmtt-8"> </span><span
|
|---|
| 6740 | class="cmtt-8"> </span><span
|
|---|
| 6741 | class="cmtt-8"> </span><span
|
|---|
| 6742 | class="cmtt-8"> 13)</span><span
|
|---|
| 6743 | class="cmtt-8"> iterate</span><span
|
|---|
| 6744 | class="cmtt-8"> [j]</span><span
|
|---|
| 6745 | class="cmtt-8"> over</span><span
|
|---|
| 6746 | class="cmtt-8"> the</span><span
|
|---|
| 6747 | class="cmtt-8"> range</span><span
|
|---|
| 6748 | class="cmtt-8"> 0</span><span
|
|---|
| 6749 | class="cmtt-8"> ...</span><span
|
|---|
| 6750 | class="cmtt-8"> [cdim]-1</span><span
|
|---|
| 6751 | class="cmtt-8"> </span><span
|
|---|
| 6752 | class="cmsy-8">{</span><br class="fancyvrb" /><a
|
|---|
| 6753 | id="x1-102040r19"></a><span
|
|---|
| 6754 | class="cmr-6">19</span>
|
|---|
| 6755 | <br class="fancyvrb" /><a
|
|---|
| 6756 | id="x1-102042r20"></a><span
|
|---|
| 6757 | class="cmr-6">20</span><span
|
|---|
| 6758 | class="cmtt-8"> </span><span
|
|---|
| 6759 | class="cmtt-8"> </span><span
|
|---|
| 6760 | class="cmtt-8"> </span><span
|
|---|
| 6761 | class="cmtt-8"> </span><span
|
|---|
| 6762 | class="cmtt-8"> </span><span
|
|---|
| 6763 | class="cmtt-8"> </span><span
|
|---|
| 6764 | class="cmtt-8"> </span><span
|
|---|
| 6765 | class="cmtt-8"> </span><span
|
|---|
| 6766 | class="cmtt-8"> </span><span
|
|---|
| 6767 | class="cmtt-8"> </span><span
|
|---|
| 6768 | class="cmtt-8"> </span><span
|
|---|
| 6769 | class="cmtt-8"> </span><span
|
|---|
| 6770 | class="cmtt-8"> 14)</span><span
|
|---|
| 6771 | class="cmtt-8"> [book]</span><span
|
|---|
| 6772 | class="cmtt-8"> =</span><span
|
|---|
| 6773 | class="cmtt-8"> array</span><span
|
|---|
| 6774 | class="cmtt-8"> [floor1</span><span
|
|---|
| 6775 | class="cmtt-8">_subclass</span><span
|
|---|
| 6776 | class="cmtt-8">_books]</span><span
|
|---|
| 6777 | class="cmtt-8"> element</span><span
|
|---|
| 6778 | class="cmtt-8"> [class],([cval]</span><span
|
|---|
| 6779 | class="cmtt-8"> bitwise</span><span
|
|---|
| 6780 | class="cmtt-8"> AND</span><span
|
|---|
| 6781 | class="cmtt-8"> [csub])</span>
|
|---|
| 6782 | <br class="fancyvrb" /><a
|
|---|
| 6783 | id="x1-102044r21"></a><span
|
|---|
| 6784 | class="cmr-6">21</span><span
|
|---|
| 6785 | class="cmtt-8"> </span><span
|
|---|
| 6786 | class="cmtt-8"> </span><span
|
|---|
| 6787 | class="cmtt-8"> </span><span
|
|---|
| 6788 | class="cmtt-8"> </span><span
|
|---|
| 6789 | class="cmtt-8"> </span><span
|
|---|
| 6790 | class="cmtt-8"> </span><span
|
|---|
| 6791 | class="cmtt-8"> </span><span
|
|---|
| 6792 | class="cmtt-8"> </span><span
|
|---|
| 6793 | class="cmtt-8"> </span><span
|
|---|
| 6794 | class="cmtt-8"> </span><span
|
|---|
| 6795 | class="cmtt-8"> </span><span
|
|---|
| 6796 | class="cmtt-8"> </span><span
|
|---|
| 6797 | class="cmtt-8"> 15)</span><span
|
|---|
| 6798 | class="cmtt-8"> [cval]</span><span
|
|---|
| 6799 | class="cmtt-8"> =</span><span
|
|---|
| 6800 | class="cmtt-8"> [cval]</span><span
|
|---|
| 6801 | class="cmtt-8"> right</span><span
|
|---|
| 6802 | class="cmtt-8"> shifted</span><span
|
|---|
| 6803 | class="cmtt-8"> [cbits]</span><span
|
|---|
| 6804 | class="cmtt-8"> bits</span><br class="fancyvrb" /><a
|
|---|
| 6805 | id="x1-102046r22"></a><span
|
|---|
| 6806 | class="cmr-6">22</span> <span
|
|---|
| 6807 | class="cmtt-8"> </span><span
|
|---|
| 6808 | class="cmtt-8"> </span><span
|
|---|
| 6809 | class="cmtt-8"> </span><span
|
|---|
| 6810 | class="cmtt-8"> </span><span
|
|---|
| 6811 | class="cmtt-8"> 16)</span><span
|
|---|
| 6812 | class="cmtt-8"> if</span><span
|
|---|
| 6813 | class="cmtt-8"> (</span><span
|
|---|
| 6814 | class="cmtt-8"> [book]</span><span
|
|---|
| 6815 | class="cmtt-8"> is</span><span
|
|---|
| 6816 | class="cmtt-8"> not</span><span
|
|---|
| 6817 | class="cmtt-8"> less</span><span
|
|---|
| 6818 | class="cmtt-8"> than</span><span
|
|---|
| 6819 | class="cmtt-8"> zero</span><span
|
|---|
| 6820 | class="cmtt-8"> )</span><span
|
|---|
| 6821 | class="cmtt-8"> </span><span
|
|---|
| 6822 | class="cmsy-8">{</span><br class="fancyvrb" /><a
|
|---|
| 6823 | id="x1-102048r23"></a><span
|
|---|
| 6824 | class="cmr-6">23</span>
|
|---|
| 6825 | <br class="fancyvrb" /><a
|
|---|
| 6826 | id="x1-102050r24"></a><span
|
|---|
| 6827 | class="cmr-6">24</span> <span
|
|---|
| 6828 | class="cmtt-8"> </span><span
|
|---|
| 6829 | class="cmtt-8"> </span><span
|
|---|
| 6830 | class="cmtt-8"> </span><span
|
|---|
| 6831 | class="cmtt-8"> </span><span
|
|---|
| 6832 | class="cmtt-8"> </span><span
|
|---|
| 6833 | class="cmtt-8"> </span><span
|
|---|
| 6834 | class="cmtt-8"> </span><span
|
|---|
| 6835 | class="cmtt-8"> </span><span
|
|---|
| 6836 | class="cmtt-8"> </span><span
|
|---|
| 6837 | class="cmtt-8"> </span><span
|
|---|
| 6838 | class="cmtt-8"> 17)</span><span
|
|---|
| 6839 | class="cmtt-8"> vector</span><span
|
|---|
| 6840 | class="cmtt-8"> [floor1</span><span
|
|---|
| 6841 | class="cmtt-8">_Y]</span><span
|
|---|
| 6842 | class="cmtt-8"> element</span><span
|
|---|
| 6843 | class="cmtt-8"> ([j]+[offset])</span><span
|
|---|
| 6844 | class="cmtt-8"> =</span><span
|
|---|
| 6845 | class="cmtt-8"> read</span><span
|
|---|
| 6846 | class="cmtt-8"> from</span><span
|
|---|
| 6847 | class="cmtt-8"> packet</span><span
|
|---|
| 6848 | class="cmtt-8"> using</span><span
|
|---|
| 6849 | class="cmtt-8"> codebook</span><br class="fancyvrb" /><a
|
|---|
| 6850 | id="x1-102052r25"></a><span
|
|---|
| 6851 | class="cmr-6">25</span><span
|
|---|
| 6852 | class="cmtt-8"> </span><span
|
|---|
| 6853 | class="cmtt-8"> </span><span
|
|---|
| 6854 | class="cmtt-8"> </span><span
|
|---|
| 6855 | class="cmtt-8"> </span><span
|
|---|
| 6856 | class="cmtt-8"> </span><span
|
|---|
| 6857 | class="cmtt-8"> </span><span
|
|---|
| 6858 | class="cmtt-8"> </span><span
|
|---|
| 6859 | class="cmtt-8"> </span><span
|
|---|
| 6860 | class="cmtt-8"> </span><span
|
|---|
| 6861 | class="cmtt-8"> </span><span
|
|---|
| 6862 | class="cmtt-8"> </span><span
|
|---|
| 6863 | class="cmtt-8"> </span><span
|
|---|
| 6864 | class="cmtt-8"> </span><span
|
|---|
| 6865 | class="cmtt-8"> </span><span
|
|---|
| 6866 | class="cmtt-8"> </span><span
|
|---|
| 6867 | class="cmtt-8"> </span><span
|
|---|
| 6868 | class="cmtt-8"> </span><span
|
|---|
| 6869 | class="cmtt-8"> </span><span
|
|---|
| 6870 | class="cmtt-8"> </span><span
|
|---|
| 6871 | class="cmtt-8"> </span><span
|
|---|
| 6872 | class="cmtt-8"> </span><span
|
|---|
| 6873 | class="cmtt-8"> </span><span
|
|---|
| 6874 | class="cmtt-8"> [book]</span><span
|
|---|
| 6875 | class="cmtt-8"> in</span><span
|
|---|
| 6876 | class="cmtt-8"> scalar</span><span
|
|---|
| 6877 | class="cmtt-8"> context</span><br class="fancyvrb" /><a
|
|---|
| 6878 | id="x1-102054r26"></a><span
|
|---|
| 6879 | class="cmr-6">26</span>
|
|---|
| 6880 | <br class="fancyvrb" /><a
|
|---|
| 6881 | id="x1-102056r27"></a><span
|
|---|
| 6882 | class="cmr-6">27</span><span
|
|---|
| 6883 | class="cmtt-8"> </span><span
|
|---|
| 6884 | class="cmtt-8"> </span><span
|
|---|
| 6885 | class="cmtt-8"> </span><span
|
|---|
| 6886 | class="cmtt-8"> </span><span
|
|---|
| 6887 | class="cmtt-8"> </span><span
|
|---|
| 6888 | class="cmtt-8"> </span><span
|
|---|
| 6889 | class="cmtt-8"> </span><span
|
|---|
| 6890 | class="cmtt-8"> </span><span
|
|---|
| 6891 | class="cmtt-8"> </span><span
|
|---|
| 6892 | class="cmtt-8"> </span><span
|
|---|
| 6893 | class="cmtt-8"> </span><span
|
|---|
| 6894 | class="cmtt-8"> </span><span
|
|---|
| 6895 | class="cmtt-8"> </span><span
|
|---|
| 6896 | class="cmtt-8"> </span><span
|
|---|
| 6897 | class="cmtt-8"> </span><span
|
|---|
| 6898 | class="cmtt-8"> </span><span
|
|---|
| 6899 | class="cmtt-8"> </span><span
|
|---|
| 6900 | class="cmsy-8">}</span><span
|
|---|
| 6901 | class="cmtt-8"> else</span><span
|
|---|
| 6902 | class="cmtt-8"> [book]</span><span
|
|---|
| 6903 | class="cmtt-8"> is</span><span
|
|---|
| 6904 | class="cmtt-8"> less</span><span
|
|---|
| 6905 | class="cmtt-8"> than</span><span
|
|---|
| 6906 | class="cmtt-8"> zero</span><span
|
|---|
| 6907 | class="cmtt-8"> </span><span
|
|---|
| 6908 | class="cmsy-8">{</span><br class="fancyvrb" /><a
|
|---|
| 6909 | id="x1-102058r28"></a><span
|
|---|
| 6910 | class="cmr-6">28</span><br class="fancyvrb" /><a
|
|---|
| 6911 | id="x1-102060r29"></a><span
|
|---|
| 6912 | class="cmr-6">29</span> <span
|
|---|
| 6913 | class="cmtt-8"> </span><span
|
|---|
| 6914 | class="cmtt-8"> </span><span
|
|---|
| 6915 | class="cmtt-8"> </span><span
|
|---|
| 6916 | class="cmtt-8"> </span><span
|
|---|
| 6917 | class="cmtt-8"> </span><span
|
|---|
| 6918 | class="cmtt-8"> </span><span
|
|---|
| 6919 | class="cmtt-8"> </span><span
|
|---|
| 6920 | class="cmtt-8"> </span><span
|
|---|
| 6921 | class="cmtt-8"> </span><span
|
|---|
| 6922 | class="cmtt-8"> </span><span
|
|---|
| 6923 | class="cmtt-8"> 18)</span><span
|
|---|
| 6924 | class="cmtt-8"> vector</span><span
|
|---|
| 6925 | class="cmtt-8"> [floor1</span><span
|
|---|
| 6926 | class="cmtt-8">_Y]</span><span
|
|---|
| 6927 | class="cmtt-8"> element</span><span
|
|---|
| 6928 | class="cmtt-8"> ([j]+[offset])</span><span
|
|---|
| 6929 | class="cmtt-8"> =</span><span
|
|---|
| 6930 | class="cmtt-8"> 0</span><br class="fancyvrb" /><a
|
|---|
| 6931 | id="x1-102062r30"></a><span
|
|---|
| 6932 | class="cmr-6">30</span>
|
|---|
| 6933 | <br class="fancyvrb" /><a
|
|---|
| 6934 | id="x1-102064r31"></a><span
|
|---|
| 6935 | class="cmr-6">31</span><span
|
|---|
| 6936 | class="cmtt-8"> </span><span
|
|---|
| 6937 | class="cmtt-8"> </span><span
|
|---|
| 6938 | class="cmtt-8"> </span><span
|
|---|
| 6939 | class="cmtt-8"> </span><span
|
|---|
| 6940 | class="cmtt-8"> </span><span
|
|---|
| 6941 | class="cmtt-8"> </span><span
|
|---|
| 6942 | class="cmtt-8"> </span><span
|
|---|
| 6943 | class="cmtt-8"> </span><span
|
|---|
| 6944 | class="cmtt-8"> </span><span
|
|---|
| 6945 | class="cmtt-8"> </span><span
|
|---|
| 6946 | class="cmtt-8"> </span><span
|
|---|
| 6947 | class="cmtt-8"> </span><span
|
|---|
| 6948 | class="cmtt-8"> </span><span
|
|---|
| 6949 | class="cmtt-8"> </span><span
|
|---|
| 6950 | class="cmtt-8"> </span><span
|
|---|
| 6951 | class="cmtt-8"> </span><span
|
|---|
| 6952 | class="cmtt-8"> </span><span
|
|---|
| 6953 | class="cmsy-8">}</span><br class="fancyvrb" /><a
|
|---|
| 6954 | id="x1-102066r32"></a><span
|
|---|
| 6955 | class="cmr-6">32</span><span
|
|---|
| 6956 | class="cmtt-8"> </span><span
|
|---|
| 6957 | class="cmtt-8"> </span><span
|
|---|
| 6958 | class="cmtt-8"> </span><span
|
|---|
| 6959 | class="cmtt-8"> </span><span
|
|---|
| 6960 | class="cmtt-8"> </span><span
|
|---|
| 6961 | class="cmtt-8"> </span><span
|
|---|
| 6962 | class="cmtt-8"> </span><span
|
|---|
| 6963 | class="cmtt-8"> </span><span
|
|---|
| 6964 | class="cmtt-8"> </span><span
|
|---|
| 6965 | class="cmtt-8"> </span><span
|
|---|
| 6966 | class="cmsy-8">}</span><br class="fancyvrb" /><a
|
|---|
| 6967 | id="x1-102068r33"></a><span
|
|---|
| 6968 | class="cmr-6">33</span><br class="fancyvrb" /><a
|
|---|
| 6969 | id="x1-102070r34"></a><span
|
|---|
| 6970 | class="cmr-6">34</span><span
|
|---|
| 6971 | class="cmtt-8"> </span><span
|
|---|
| 6972 | class="cmtt-8"> </span><span
|
|---|
| 6973 | class="cmtt-8"> </span><span
|
|---|
| 6974 | class="cmtt-8"> </span><span
|
|---|
| 6975 | class="cmtt-8"> </span><span
|
|---|
| 6976 | class="cmtt-8"> 19)</span><span
|
|---|
| 6977 | class="cmtt-8"> [offset]</span><span
|
|---|
| 6978 | class="cmtt-8"> =</span><span
|
|---|
| 6979 | class="cmtt-8"> [offset]</span><span
|
|---|
| 6980 | class="cmtt-8"> +</span><span
|
|---|
| 6981 | class="cmtt-8"> [cdim]</span><br class="fancyvrb" /><a
|
|---|
| 6982 | id="x1-102072r35"></a><span
|
|---|
| 6983 | class="cmr-6">35</span><br class="fancyvrb" /><a
|
|---|
| 6984 | id="x1-102074r36"></a><span
|
|---|
| 6985 | class="cmr-6">36</span><span
|
|---|
| 6986 | class="cmtt-8"> </span><span
|
|---|
| 6987 | class="cmtt-8"> </span><span
|
|---|
| 6988 | class="cmtt-8"> </span><span
|
|---|
| 6989 | class="cmtt-8"> </span><span
|
|---|
| 6990 | class="cmtt-8"> </span><span
|
|---|
| 6991 | class="cmsy-8">}</span><br class="fancyvrb" /><a
|
|---|
| 6992 | id="x1-102076r37"></a><span
|
|---|
| 6993 | class="cmr-6">37</span><br class="fancyvrb" /><a
|
|---|
| 6994 | id="x1-102078r38"></a><span
|
|---|
| 6995 | class="cmr-6">38</span><span
|
|---|
| 6996 | class="cmtt-8"> 20)</span><span
|
|---|
| 6997 | class="cmtt-8"> done</span></div>
|
|---|
| 6998 | <!--l. 228--><p class="noindent" >An end-of-packet condition during curve decode should be considered a nominal occurrence; if
|
|---|
| 6999 | end-of-packet is reached during any read operation above, floor decode is to return ’unused’
|
|---|
| 7000 | status as if the <span
|
|---|
| 7001 | class="cmtt-12">[nonzero] </span>flag had been unset at the beginning of decode.
|
|---|
| 7002 | <!--l. 234--><p class="noindent" >Vector <span
|
|---|
| 7003 | class="cmtt-12">[floor1</span><span
|
|---|
| 7004 | class="cmtt-12">_Y] </span>contains the values from packet decode needed for floor 1 synthesis.
|
|---|
| 7005 | <!--l. 239--><p class="noindent" >
|
|---|
| 7006 | <h5 class="subsubsectionHead"><span class="titlemark">7.2.4. </span> <a
|
|---|
| 7007 | id="x1-1030007.2.4"></a>curve computation</h5>
|
|---|
| 7008 | <!--l. 241--><p class="noindent" >Curve computation is split into two logical steps; the first step derives final Y amplitude values
|
|---|
| 7009 | from the encoded, wrapped difference values taken from the bitstream. The second step
|
|---|
| 7010 | plots the curve lines. Also, although zero-difference values are used in the iterative
|
|---|
| 7011 | prediction to find final Y values, these points are conditionally skipped during final
|
|---|
| 7012 | line computation in step two. Skipping zero-difference values allows a smoother line
|
|---|
| 7013 | fit.
|
|---|
| 7014 | <!--l. 249--><p class="noindent" >Although some aspects of the below algorithm look like inconsequential optimizations,
|
|---|
| 7015 | implementors are warned to follow the details closely. Deviation from implementing a strictly
|
|---|
| 7016 | equivalent algorithm can result in serious decoding errors.
|
|---|
| 7017 | <!--l. 254--><p class="noindent" ><span
|
|---|
| 7018 | class="cmti-12">Additional note: </span>Although <span
|
|---|
| 7019 | class="cmtt-12">[floor1</span><span
|
|---|
| 7020 | class="cmtt-12">_final</span><span
|
|---|
| 7021 | class="cmtt-12">_Y] </span>values in the prediction loop and at the end of
|
|---|
| 7022 | step 1 are inherently limited by the prediction algorithm to [0, <span
|
|---|
| 7023 | class="cmtt-12">[range]</span>), it is possible to abuse
|
|---|
| 7024 | the setup and codebook machinery to produce negative or over-range results. We suggest that
|
|---|
| 7025 | decoder implementations guard the values in vector <span
|
|---|
| 7026 | class="cmtt-12">[floor1</span><span
|
|---|
| 7027 | class="cmtt-12">_final</span><span
|
|---|
| 7028 | class="cmtt-12">_Y] </span>by clamping each
|
|---|
| 7029 | element to [0, <span
|
|---|
| 7030 | class="cmtt-12">[range]</span>) after step 1. Variants of this suggestion are acceptable as valid floor1
|
|---|
| 7031 | setups cannot produce out of range values.
|
|---|
| 7032 | <!--l. 265--><p class="noindent" >
|
|---|
| 7033 | <dl class="description"><dt class="description">
|
|---|
| 7034 | <span
|
|---|
| 7035 | class="cmssbx-10x-x-120">step 1: amplitude value synthesis</span> </dt><dd
|
|---|
| 7036 | class="description">
|
|---|
| 7037 | <!--l. 267--><p class="noindent" >Unwrap the always-positive-or-zero values read from the packet into +/- difference
|
|---|
| 7038 | values, then apply to line prediction.
|
|---|
| 7039 |
|
|---|
| 7040 |
|
|---|
| 7041 |
|
|---|
| 7042 | <!--l. 270--><p class="noindent" >
|
|---|
| 7043 | <div class="fancyvrb" id="fancyvrb31"><a
|
|---|
| 7044 | id="x1-103002r1"></a><span
|
|---|
| 7045 | class="cmr-6">1</span><span
|
|---|
| 7046 | class="cmtt-8"> </span><span
|
|---|
| 7047 | class="cmtt-8"> 1)</span><span
|
|---|
| 7048 | class="cmtt-8"> [range]</span><span
|
|---|
| 7049 | class="cmtt-8"> =</span><span
|
|---|
| 7050 | class="cmtt-8"> vector</span><span
|
|---|
| 7051 | class="cmtt-8"> </span><span
|
|---|
| 7052 | class="cmsy-8">{</span><span
|
|---|
| 7053 | class="cmtt-8"> 256,</span><span
|
|---|
| 7054 | class="cmtt-8"> 128,</span><span
|
|---|
| 7055 | class="cmtt-8"> 86,</span><span
|
|---|
| 7056 | class="cmtt-8"> 64</span><span
|
|---|
| 7057 | class="cmtt-8"> </span><span
|
|---|
| 7058 | class="cmsy-8">}</span><span
|
|---|
| 7059 | class="cmtt-8"> element</span><span
|
|---|
| 7060 | class="cmtt-8"> ([floor1</span><span
|
|---|
| 7061 | class="cmtt-8">_multiplier]-1)</span><br class="fancyvrb" /><a
|
|---|
| 7062 | id="x1-103004r2"></a><span
|
|---|
| 7063 | class="cmr-6">2</span><span
|
|---|
| 7064 | class="cmtt-8"> </span><span
|
|---|
| 7065 | class="cmtt-8"> 2)</span><span
|
|---|
| 7066 | class="cmtt-8"> vector</span><span
|
|---|
| 7067 | class="cmtt-8"> [floor1</span><span
|
|---|
| 7068 | class="cmtt-8">_step2</span><span
|
|---|
| 7069 | class="cmtt-8">_flag]</span><span
|
|---|
| 7070 | class="cmtt-8"> element</span><span
|
|---|
| 7071 | class="cmtt-8"> [0]</span><span
|
|---|
| 7072 | class="cmtt-8"> =</span><span
|
|---|
| 7073 | class="cmtt-8"> set</span>
|
|---|
| 7074 | <br class="fancyvrb" /><a
|
|---|
| 7075 | id="x1-103006r3"></a><span
|
|---|
| 7076 | class="cmr-6">3</span><span
|
|---|
| 7077 | class="cmtt-8"> </span><span
|
|---|
| 7078 | class="cmtt-8"> 3)</span><span
|
|---|
| 7079 | class="cmtt-8"> vector</span><span
|
|---|
| 7080 | class="cmtt-8"> [floor1</span><span
|
|---|
| 7081 | class="cmtt-8">_step2</span><span
|
|---|
| 7082 | class="cmtt-8">_flag]</span><span
|
|---|
| 7083 | class="cmtt-8"> element</span><span
|
|---|
| 7084 | class="cmtt-8"> [1]</span><span
|
|---|
| 7085 | class="cmtt-8"> =</span><span
|
|---|
| 7086 | class="cmtt-8"> set</span><br class="fancyvrb" /><a
|
|---|
| 7087 | id="x1-103008r4"></a><span
|
|---|
| 7088 | class="cmr-6">4</span><span
|
|---|
| 7089 | class="cmtt-8"> </span><span
|
|---|
| 7090 | class="cmtt-8"> 4)</span><span
|
|---|
| 7091 | class="cmtt-8"> vector</span><span
|
|---|
| 7092 | class="cmtt-8"> [floor1</span><span
|
|---|
| 7093 | class="cmtt-8">_final</span><span
|
|---|
| 7094 | class="cmtt-8">_Y]</span><span
|
|---|
| 7095 | class="cmtt-8"> element</span><span
|
|---|
| 7096 | class="cmtt-8"> [0]</span><span
|
|---|
| 7097 | class="cmtt-8"> =</span><span
|
|---|
| 7098 | class="cmtt-8"> vector</span><span
|
|---|
| 7099 | class="cmtt-8"> [floor1</span><span
|
|---|
| 7100 | class="cmtt-8">_Y]</span><span
|
|---|
| 7101 | class="cmtt-8"> element</span><span
|
|---|
| 7102 | class="cmtt-8"> [0]</span>
|
|---|
| 7103 | <br class="fancyvrb" /><a
|
|---|
| 7104 | id="x1-103010r5"></a><span
|
|---|
| 7105 | class="cmr-6">5</span><span
|
|---|
| 7106 | class="cmtt-8"> </span><span
|
|---|
| 7107 | class="cmtt-8"> 5)</span><span
|
|---|
| 7108 | class="cmtt-8"> vector</span><span
|
|---|
| 7109 | class="cmtt-8"> [floor1</span><span
|
|---|
| 7110 | class="cmtt-8">_final</span><span
|
|---|
| 7111 | class="cmtt-8">_Y]</span><span
|
|---|
| 7112 | class="cmtt-8"> element</span><span
|
|---|
| 7113 | class="cmtt-8"> [1]</span><span
|
|---|
| 7114 | class="cmtt-8"> =</span><span
|
|---|
| 7115 | class="cmtt-8"> vector</span><span
|
|---|
| 7116 | class="cmtt-8"> [floor1</span><span
|
|---|
| 7117 | class="cmtt-8">_Y]</span><span
|
|---|
| 7118 | class="cmtt-8"> element</span><span
|
|---|
| 7119 | class="cmtt-8"> [1]</span><br class="fancyvrb" /><a
|
|---|
| 7120 | id="x1-103012r6"></a><span
|
|---|
| 7121 | class="cmr-6">6</span><span
|
|---|
| 7122 | class="cmtt-8"> </span><span
|
|---|
| 7123 | class="cmtt-8"> 6)</span><span
|
|---|
| 7124 | class="cmtt-8"> iterate</span><span
|
|---|
| 7125 | class="cmtt-8"> [i]</span><span
|
|---|
| 7126 | class="cmtt-8"> over</span><span
|
|---|
| 7127 | class="cmtt-8"> the</span><span
|
|---|
| 7128 | class="cmtt-8"> range</span><span
|
|---|
| 7129 | class="cmtt-8"> 2</span><span
|
|---|
| 7130 | class="cmtt-8"> ...</span><span
|
|---|
| 7131 | class="cmtt-8"> [floor1</span><span
|
|---|
| 7132 | class="cmtt-8">_values]-1</span><span
|
|---|
| 7133 | class="cmtt-8"> </span><span
|
|---|
| 7134 | class="cmsy-8">{</span><br class="fancyvrb" /><a
|
|---|
| 7135 | id="x1-103014r7"></a><span
|
|---|
| 7136 | class="cmr-6">7</span>
|
|---|
| 7137 | <br class="fancyvrb" /><a
|
|---|
| 7138 | id="x1-103016r8"></a><span
|
|---|
| 7139 | class="cmr-6">8</span><span
|
|---|
| 7140 | class="cmtt-8"> </span><span
|
|---|
| 7141 | class="cmtt-8"> </span><span
|
|---|
| 7142 | class="cmtt-8"> </span><span
|
|---|
| 7143 | class="cmtt-8"> </span><span
|
|---|
| 7144 | class="cmtt-8"> </span><span
|
|---|
| 7145 | class="cmtt-8"> </span><span
|
|---|
| 7146 | class="cmtt-8"> 7)</span><span
|
|---|
| 7147 | class="cmtt-8"> [low</span><span
|
|---|
| 7148 | class="cmtt-8">_neighbor</span><span
|
|---|
| 7149 | class="cmtt-8">_offset]</span><span
|
|---|
| 7150 | class="cmtt-8"> =</span><span
|
|---|
| 7151 | class="cmtt-8"> </span><a
|
|---|
| 7152 | href="#x1-1220009.2.4"><span
|
|---|
| 7153 | class="cmtt-8">low</span><span
|
|---|
| 7154 | class="cmtt-8">_neighbor</span></a><span
|
|---|
| 7155 | class="cmtt-8">([floor1</span><span
|
|---|
| 7156 | class="cmtt-8">_X</span><span
|
|---|
| 7157 | class="cmtt-8">_list],[i])</span><br class="fancyvrb" /><a
|
|---|
| 7158 | id="x1-103018r9"></a><span
|
|---|
| 7159 | class="cmr-6">9</span><span
|
|---|
| 7160 | class="cmtt-8"> </span><span
|
|---|
| 7161 | class="cmtt-8"> </span><span
|
|---|
| 7162 | class="cmtt-8"> </span><span
|
|---|
| 7163 | class="cmtt-8"> </span><span
|
|---|
| 7164 | class="cmtt-8"> </span><span
|
|---|
| 7165 | class="cmtt-8"> </span><span
|
|---|
| 7166 | class="cmtt-8"> 8)</span><span
|
|---|
| 7167 | class="cmtt-8"> [high</span><span
|
|---|
| 7168 | class="cmtt-8">_neighbor</span><span
|
|---|
| 7169 | class="cmtt-8">_offset]</span><span
|
|---|
| 7170 | class="cmtt-8"> =</span><span
|
|---|
| 7171 | class="cmtt-8"> </span><a
|
|---|
| 7172 | href="#x1-1230009.2.5"><span
|
|---|
| 7173 | class="cmtt-8">high</span><span
|
|---|
| 7174 | class="cmtt-8">_neighbor</span></a><span
|
|---|
| 7175 | class="cmtt-8">([floor1</span><span
|
|---|
| 7176 | class="cmtt-8">_X</span><span
|
|---|
| 7177 | class="cmtt-8">_list],[i])</span><br class="fancyvrb" /><a
|
|---|
| 7178 | id="x1-103020r10"></a><span
|
|---|
| 7179 | class="cmr-6">10</span>
|
|---|
| 7180 | <br class="fancyvrb" /><a
|
|---|
| 7181 | id="x1-103022r11"></a><span
|
|---|
| 7182 | class="cmr-6">11</span><span
|
|---|
| 7183 | class="cmtt-8"> </span><span
|
|---|
| 7184 | class="cmtt-8"> </span><span
|
|---|
| 7185 | class="cmtt-8"> </span><span
|
|---|
| 7186 | class="cmtt-8"> </span><span
|
|---|
| 7187 | class="cmtt-8"> </span><span
|
|---|
| 7188 | class="cmtt-8"> </span><span
|
|---|
| 7189 | class="cmtt-8"> 9)</span><span
|
|---|
| 7190 | class="cmtt-8"> [predicted]</span><span
|
|---|
| 7191 | class="cmtt-8"> =</span><span
|
|---|
| 7192 | class="cmtt-8"> </span><a
|
|---|
| 7193 | href="#x1-1240009.2.6"><span
|
|---|
| 7194 | class="cmtt-8">render</span><span
|
|---|
| 7195 | class="cmtt-8">_point</span></a><span
|
|---|
| 7196 | class="cmtt-8">(</span><span
|
|---|
| 7197 | class="cmtt-8"> vector</span><span
|
|---|
| 7198 | class="cmtt-8"> [floor1</span><span
|
|---|
| 7199 | class="cmtt-8">_X</span><span
|
|---|
| 7200 | class="cmtt-8">_list]</span><span
|
|---|
| 7201 | class="cmtt-8"> element</span><span
|
|---|
| 7202 | class="cmtt-8"> [low</span><span
|
|---|
| 7203 | class="cmtt-8">_neighbor</span><span
|
|---|
| 7204 | class="cmtt-8">_offset],</span>
|
|---|
| 7205 | <br class="fancyvrb" /><a
|
|---|
| 7206 | id="x1-103024r12"></a><span
|
|---|
| 7207 | class="cmr-6">12</span> <span
|
|---|
| 7208 | class="cmtt-8"> </span><span
|
|---|
| 7209 | class="cmtt-8"> </span><span
|
|---|
| 7210 | class="cmtt-8"> </span><span
|
|---|
| 7211 | class="cmtt-8"> </span><span
|
|---|
| 7212 | class="cmtt-8"> </span><span
|
|---|
| 7213 | class="cmtt-8"> vector</span><span
|
|---|
| 7214 | class="cmtt-8"> [floor1</span><span
|
|---|
| 7215 | class="cmtt-8">_final</span><span
|
|---|
| 7216 | class="cmtt-8">_Y]</span><span
|
|---|
| 7217 | class="cmtt-8"> element</span><span
|
|---|
| 7218 | class="cmtt-8"> [low</span><span
|
|---|
| 7219 | class="cmtt-8">_neighbor</span><span
|
|---|
| 7220 | class="cmtt-8">_offset],</span>
|
|---|
| 7221 | <br class="fancyvrb" /><a
|
|---|
| 7222 | id="x1-103026r13"></a><span
|
|---|
| 7223 | class="cmr-6">13</span><span
|
|---|
| 7224 | class="cmtt-8"> </span><span
|
|---|
| 7225 | class="cmtt-8"> </span><span
|
|---|
| 7226 | class="cmtt-8"> </span><span
|
|---|
| 7227 | class="cmtt-8"> </span><span
|
|---|
| 7228 | class="cmtt-8"> </span><span
|
|---|
| 7229 | class="cmtt-8"> </span><span
|
|---|
| 7230 | class="cmtt-8"> </span><span
|
|---|
| 7231 | class="cmtt-8"> </span><span
|
|---|
| 7232 | class="cmtt-8"> </span><span
|
|---|
| 7233 | class="cmtt-8"> </span><span
|
|---|
| 7234 | class="cmtt-8"> </span><span
|
|---|
| 7235 | class="cmtt-8"> </span><span
|
|---|
| 7236 | class="cmtt-8"> </span><span
|
|---|
| 7237 | class="cmtt-8"> </span><span
|
|---|
| 7238 | class="cmtt-8"> </span><span
|
|---|
| 7239 | class="cmtt-8"> </span><span
|
|---|
| 7240 | class="cmtt-8"> </span><span
|
|---|
| 7241 | class="cmtt-8"> </span><span
|
|---|
| 7242 | class="cmtt-8"> </span><span
|
|---|
| 7243 | class="cmtt-8"> </span><span
|
|---|
| 7244 | class="cmtt-8"> </span><span
|
|---|
| 7245 | class="cmtt-8"> </span><span
|
|---|
| 7246 | class="cmtt-8"> </span><span
|
|---|
| 7247 | class="cmtt-8"> </span><span
|
|---|
| 7248 | class="cmtt-8"> </span><span
|
|---|
| 7249 | class="cmtt-8"> </span><span
|
|---|
| 7250 | class="cmtt-8"> </span><span
|
|---|
| 7251 | class="cmtt-8"> </span><span
|
|---|
| 7252 | class="cmtt-8"> </span><span
|
|---|
| 7253 | class="cmtt-8"> </span><span
|
|---|
| 7254 | class="cmtt-8"> </span><span
|
|---|
| 7255 | class="cmtt-8"> </span><span
|
|---|
| 7256 | class="cmtt-8"> </span><span
|
|---|
| 7257 | class="cmtt-8"> </span><span
|
|---|
| 7258 | class="cmtt-8"> </span><span
|
|---|
| 7259 | class="cmtt-8"> </span><span
|
|---|
| 7260 | class="cmtt-8"> </span><span
|
|---|
| 7261 | class="cmtt-8"> vector</span><span
|
|---|
| 7262 | class="cmtt-8"> [floor1</span><span
|
|---|
| 7263 | class="cmtt-8">_X</span><span
|
|---|
| 7264 | class="cmtt-8">_list]</span><span
|
|---|
| 7265 | class="cmtt-8"> element</span><span
|
|---|
| 7266 | class="cmtt-8"> [high</span><span
|
|---|
| 7267 | class="cmtt-8">_neighbor</span><span
|
|---|
| 7268 | class="cmtt-8">_offset],</span>
|
|---|
| 7269 | <br class="fancyvrb" /><a
|
|---|
| 7270 | id="x1-103028r14"></a><span
|
|---|
| 7271 | class="cmr-6">14</span> <span
|
|---|
| 7272 | class="cmtt-8"> </span><span
|
|---|
| 7273 | class="cmtt-8"> </span><span
|
|---|
| 7274 | class="cmtt-8"> </span><span
|
|---|
| 7275 | class="cmtt-8"> </span><span
|
|---|
| 7276 | class="cmtt-8"> </span><span
|
|---|
| 7277 | class="cmtt-8"> vector</span><span
|
|---|
| 7278 | class="cmtt-8"> [floor1</span><span
|
|---|
| 7279 | class="cmtt-8">_final</span><span
|
|---|
| 7280 | class="cmtt-8">_Y]</span><span
|
|---|
| 7281 | class="cmtt-8"> element</span><span
|
|---|
| 7282 | class="cmtt-8"> [high</span><span
|
|---|
| 7283 | class="cmtt-8">_neighbor</span><span
|
|---|
| 7284 | class="cmtt-8">_offset],</span>
|
|---|
| 7285 | <br class="fancyvrb" /><a
|
|---|
| 7286 | id="x1-103030r15"></a><span
|
|---|
| 7287 | class="cmr-6">15</span><span
|
|---|
| 7288 | class="cmtt-8"> </span><span
|
|---|
| 7289 | class="cmtt-8"> </span><span
|
|---|
| 7290 | class="cmtt-8"> </span><span
|
|---|
| 7291 | class="cmtt-8"> </span><span
|
|---|
| 7292 | class="cmtt-8"> </span><span
|
|---|
| 7293 | class="cmtt-8"> </span><span
|
|---|
| 7294 | class="cmtt-8"> </span><span
|
|---|
| 7295 | class="cmtt-8"> </span><span
|
|---|
| 7296 | class="cmtt-8"> </span><span
|
|---|
| 7297 | class="cmtt-8"> </span><span
|
|---|
| 7298 | class="cmtt-8"> </span><span
|
|---|
| 7299 | class="cmtt-8"> </span><span
|
|---|
| 7300 | class="cmtt-8"> </span><span
|
|---|
| 7301 | class="cmtt-8"> </span><span
|
|---|
| 7302 | class="cmtt-8"> </span><span
|
|---|
| 7303 | class="cmtt-8"> </span><span
|
|---|
| 7304 | class="cmtt-8"> </span><span
|
|---|
| 7305 | class="cmtt-8"> </span><span
|
|---|
| 7306 | class="cmtt-8"> </span><span
|
|---|
| 7307 | class="cmtt-8"> </span><span
|
|---|
| 7308 | class="cmtt-8"> </span><span
|
|---|
| 7309 | class="cmtt-8"> </span><span
|
|---|
| 7310 | class="cmtt-8"> </span><span
|
|---|
| 7311 | class="cmtt-8"> </span><span
|
|---|
| 7312 | class="cmtt-8"> </span><span
|
|---|
| 7313 | class="cmtt-8"> </span><span
|
|---|
| 7314 | class="cmtt-8"> </span><span
|
|---|
| 7315 | class="cmtt-8"> </span><span
|
|---|
| 7316 | class="cmtt-8"> </span><span
|
|---|
| 7317 | class="cmtt-8"> </span><span
|
|---|
| 7318 | class="cmtt-8"> </span><span
|
|---|
| 7319 | class="cmtt-8"> </span><span
|
|---|
| 7320 | class="cmtt-8"> </span><span
|
|---|
| 7321 | class="cmtt-8"> </span><span
|
|---|
| 7322 | class="cmtt-8"> </span><span
|
|---|
| 7323 | class="cmtt-8"> </span><span
|
|---|
| 7324 | class="cmtt-8"> </span><span
|
|---|
| 7325 | class="cmtt-8"> vector</span><span
|
|---|
| 7326 | class="cmtt-8"> [floor1</span><span
|
|---|
| 7327 | class="cmtt-8">_X</span><span
|
|---|
| 7328 | class="cmtt-8">_list]</span><span
|
|---|
| 7329 | class="cmtt-8"> element</span><span
|
|---|
| 7330 | class="cmtt-8"> [i]</span><span
|
|---|
| 7331 | class="cmtt-8"> )</span><br class="fancyvrb" /><a
|
|---|
| 7332 | id="x1-103032r16"></a><span
|
|---|
| 7333 | class="cmr-6">16</span><br class="fancyvrb" /><a
|
|---|
| 7334 | id="x1-103034r17"></a><span
|
|---|
| 7335 | class="cmr-6">17</span><span
|
|---|
| 7336 | class="cmtt-8"> </span><span
|
|---|
| 7337 | class="cmtt-8"> </span><span
|
|---|
| 7338 | class="cmtt-8"> </span><span
|
|---|
| 7339 | class="cmtt-8"> </span><span
|
|---|
| 7340 | class="cmtt-8"> </span><span
|
|---|
| 7341 | class="cmtt-8"> 10)</span><span
|
|---|
| 7342 | class="cmtt-8"> [val]</span><span
|
|---|
| 7343 | class="cmtt-8"> =</span><span
|
|---|
| 7344 | class="cmtt-8"> vector</span><span
|
|---|
| 7345 | class="cmtt-8"> [floor1</span><span
|
|---|
| 7346 | class="cmtt-8">_Y]</span><span
|
|---|
| 7347 | class="cmtt-8"> element</span><span
|
|---|
| 7348 | class="cmtt-8"> [i]</span>
|
|---|
| 7349 | <br class="fancyvrb" /><a
|
|---|
| 7350 | id="x1-103036r18"></a><span
|
|---|
| 7351 | class="cmr-6">18</span><span
|
|---|
| 7352 | class="cmtt-8"> </span><span
|
|---|
| 7353 | class="cmtt-8"> </span><span
|
|---|
| 7354 | class="cmtt-8"> </span><span
|
|---|
| 7355 | class="cmtt-8"> </span><span
|
|---|
| 7356 | class="cmtt-8"> </span><span
|
|---|
| 7357 | class="cmtt-8"> 11)</span><span
|
|---|
| 7358 | class="cmtt-8"> [highroom]</span><span
|
|---|
| 7359 | class="cmtt-8"> =</span><span
|
|---|
| 7360 | class="cmtt-8"> [range]</span><span
|
|---|
| 7361 | class="cmtt-8"> -</span><span
|
|---|
| 7362 | class="cmtt-8"> [predicted]</span><br class="fancyvrb" /><a
|
|---|
| 7363 | id="x1-103038r19"></a><span
|
|---|
| 7364 | class="cmr-6">19</span><span
|
|---|
| 7365 | class="cmtt-8"> </span><span
|
|---|
| 7366 | class="cmtt-8"> </span><span
|
|---|
| 7367 | class="cmtt-8"> </span><span
|
|---|
| 7368 | class="cmtt-8"> </span><span
|
|---|
| 7369 | class="cmtt-8"> </span><span
|
|---|
| 7370 | class="cmtt-8"> 12)</span><span
|
|---|
| 7371 | class="cmtt-8"> [lowroom]</span><span
|
|---|
| 7372 | class="cmtt-8"> </span><span
|
|---|
| 7373 | class="cmtt-8"> =</span><span
|
|---|
| 7374 | class="cmtt-8"> [predicted]</span><br class="fancyvrb" /><a
|
|---|
| 7375 | id="x1-103040r20"></a><span
|
|---|
| 7376 | class="cmr-6">20</span><span
|
|---|
| 7377 | class="cmtt-8"> </span><span
|
|---|
| 7378 | class="cmtt-8"> </span><span
|
|---|
| 7379 | class="cmtt-8"> </span><span
|
|---|
| 7380 | class="cmtt-8"> </span><span
|
|---|
| 7381 | class="cmtt-8"> </span><span
|
|---|
| 7382 | class="cmtt-8"> 13)</span><span
|
|---|
| 7383 | class="cmtt-8"> if</span><span
|
|---|
| 7384 | class="cmtt-8"> (</span><span
|
|---|
| 7385 | class="cmtt-8"> [highroom]</span><span
|
|---|
| 7386 | class="cmtt-8"> is</span><span
|
|---|
| 7387 | class="cmtt-8"> less</span><span
|
|---|
| 7388 | class="cmtt-8"> than</span><span
|
|---|
| 7389 | class="cmtt-8"> [lowroom]</span><span
|
|---|
| 7390 | class="cmtt-8"> )</span><span
|
|---|
| 7391 | class="cmtt-8"> </span><span
|
|---|
| 7392 | class="cmsy-8">{</span><br class="fancyvrb" /><a
|
|---|
| 7393 | id="x1-103042r21"></a><span
|
|---|
| 7394 | class="cmr-6">21</span>
|
|---|
| 7395 | <br class="fancyvrb" /><a
|
|---|
| 7396 | id="x1-103044r22"></a><span
|
|---|
| 7397 | class="cmr-6">22</span><span
|
|---|
| 7398 | class="cmtt-8"> </span><span
|
|---|
| 7399 | class="cmtt-8"> </span><span
|
|---|
| 7400 | class="cmtt-8"> </span><span
|
|---|
| 7401 | class="cmtt-8"> </span><span
|
|---|
| 7402 | class="cmtt-8"> </span><span
|
|---|
| 7403 | class="cmtt-8"> </span><span
|
|---|
| 7404 | class="cmtt-8"> </span><span
|
|---|
| 7405 | class="cmtt-8"> </span><span
|
|---|
| 7406 | class="cmtt-8"> </span><span
|
|---|
| 7407 | class="cmtt-8"> </span><span
|
|---|
| 7408 | class="cmtt-8"> </span><span
|
|---|
| 7409 | class="cmtt-8"> 14)</span><span
|
|---|
| 7410 | class="cmtt-8"> [room]</span><span
|
|---|
| 7411 | class="cmtt-8"> =</span><span
|
|---|
| 7412 | class="cmtt-8"> [highroom]</span><span
|
|---|
| 7413 | class="cmtt-8"> *</span><span
|
|---|
| 7414 | class="cmtt-8"> 2</span><br class="fancyvrb" /><a
|
|---|
| 7415 | id="x1-103046r23"></a><span
|
|---|
| 7416 | class="cmr-6">23</span><br class="fancyvrb" /><a
|
|---|
| 7417 | id="x1-103048r24"></a><span
|
|---|
| 7418 | class="cmr-6">24</span><span
|
|---|
| 7419 | class="cmtt-8"> </span><span
|
|---|
| 7420 | class="cmtt-8"> </span><span
|
|---|
| 7421 | class="cmtt-8"> </span><span
|
|---|
| 7422 | class="cmtt-8"> </span><span
|
|---|
| 7423 | class="cmtt-8"> </span><span
|
|---|
| 7424 | class="cmtt-8"> </span><span
|
|---|
| 7425 | class="cmtt-8"> </span><span
|
|---|
| 7426 | class="cmtt-8"> </span><span
|
|---|
| 7427 | class="cmtt-8"> </span><span
|
|---|
| 7428 | class="cmtt-8"> </span><span
|
|---|
| 7429 | class="cmsy-8">}</span><span
|
|---|
| 7430 | class="cmtt-8"> else</span><span
|
|---|
| 7431 | class="cmtt-8"> [highroom]</span><span
|
|---|
| 7432 | class="cmtt-8"> is</span><span
|
|---|
| 7433 | class="cmtt-8"> not</span><span
|
|---|
| 7434 | class="cmtt-8"> less</span><span
|
|---|
| 7435 | class="cmtt-8"> than</span><span
|
|---|
| 7436 | class="cmtt-8"> [lowroom]</span><span
|
|---|
| 7437 | class="cmtt-8"> </span><span
|
|---|
| 7438 | class="cmsy-8">{</span><br class="fancyvrb" /><a
|
|---|
| 7439 | id="x1-103050r25"></a><span
|
|---|
| 7440 | class="cmr-6">25</span><br class="fancyvrb" /><a
|
|---|
| 7441 | id="x1-103052r26"></a><span
|
|---|
| 7442 | class="cmr-6">26</span><span
|
|---|
| 7443 | class="cmtt-8"> </span><span
|
|---|
| 7444 | class="cmtt-8"> </span><span
|
|---|
| 7445 | class="cmtt-8"> </span><span
|
|---|
| 7446 | class="cmtt-8"> </span><span
|
|---|
| 7447 | class="cmtt-8"> </span><span
|
|---|
| 7448 | class="cmtt-8"> </span><span
|
|---|
| 7449 | class="cmtt-8"> </span><span
|
|---|
| 7450 | class="cmtt-8"> </span><span
|
|---|
| 7451 | class="cmtt-8"> </span><span
|
|---|
| 7452 | class="cmtt-8"> </span><span
|
|---|
| 7453 | class="cmtt-8"> </span><span
|
|---|
| 7454 | class="cmtt-8"> 15)</span><span
|
|---|
| 7455 | class="cmtt-8"> [room]</span><span
|
|---|
| 7456 | class="cmtt-8"> =</span><span
|
|---|
| 7457 | class="cmtt-8"> [lowroom]</span><span
|
|---|
| 7458 | class="cmtt-8"> *</span><span
|
|---|
| 7459 | class="cmtt-8"> 2</span><br class="fancyvrb" /><a
|
|---|
| 7460 | id="x1-103054r27"></a><span
|
|---|
| 7461 | class="cmr-6">27</span>
|
|---|
| 7462 | <br class="fancyvrb" /><a
|
|---|
| 7463 | id="x1-103056r28"></a><span
|
|---|
| 7464 | class="cmr-6">28</span><span
|
|---|
| 7465 | class="cmtt-8"> </span><span
|
|---|
| 7466 | class="cmtt-8"> </span><span
|
|---|
| 7467 | class="cmtt-8"> </span><span
|
|---|
| 7468 | class="cmtt-8"> </span><span
|
|---|
| 7469 | class="cmtt-8"> </span><span
|
|---|
| 7470 | class="cmtt-8"> </span><span
|
|---|
| 7471 | class="cmtt-8"> </span><span
|
|---|
| 7472 | class="cmtt-8"> </span><span
|
|---|
| 7473 | class="cmtt-8"> </span><span
|
|---|
| 7474 | class="cmtt-8"> </span><span
|
|---|
| 7475 | class="cmsy-8">}</span><br class="fancyvrb" /><a
|
|---|
| 7476 | id="x1-103058r29"></a><span
|
|---|
| 7477 | class="cmr-6">29</span><br class="fancyvrb" /><a
|
|---|
| 7478 | id="x1-103060r30"></a><span
|
|---|
| 7479 | class="cmr-6">30</span><span
|
|---|
| 7480 | class="cmtt-8"> </span><span
|
|---|
| 7481 | class="cmtt-8"> </span><span
|
|---|
| 7482 | class="cmtt-8"> </span><span
|
|---|
| 7483 | class="cmtt-8"> </span><span
|
|---|
| 7484 | class="cmtt-8"> </span><span
|
|---|
| 7485 | class="cmtt-8"> 16)</span><span
|
|---|
| 7486 | class="cmtt-8"> if</span><span
|
|---|
| 7487 | class="cmtt-8"> (</span><span
|
|---|
| 7488 | class="cmtt-8"> [val]</span><span
|
|---|
| 7489 | class="cmtt-8"> is</span><span
|
|---|
| 7490 | class="cmtt-8"> nonzero</span><span
|
|---|
| 7491 | class="cmtt-8"> )</span><span
|
|---|
| 7492 | class="cmtt-8"> </span><span
|
|---|
| 7493 | class="cmsy-8">{</span><br class="fancyvrb" /><a
|
|---|
| 7494 | id="x1-103062r31"></a><span
|
|---|
| 7495 | class="cmr-6">31</span><br class="fancyvrb" /><a
|
|---|
| 7496 | id="x1-103064r32"></a><span
|
|---|
| 7497 | class="cmr-6">32</span><span
|
|---|
| 7498 | class="cmtt-8"> </span><span
|
|---|
| 7499 | class="cmtt-8"> </span><span
|
|---|
| 7500 | class="cmtt-8"> </span><span
|
|---|
| 7501 | class="cmtt-8"> </span><span
|
|---|
| 7502 | class="cmtt-8"> </span><span
|
|---|
| 7503 | class="cmtt-8"> </span><span
|
|---|
| 7504 | class="cmtt-8"> </span><span
|
|---|
| 7505 | class="cmtt-8"> </span><span
|
|---|
| 7506 | class="cmtt-8"> </span><span
|
|---|
| 7507 | class="cmtt-8"> </span><span
|
|---|
| 7508 | class="cmtt-8"> </span><span
|
|---|
| 7509 | class="cmtt-8"> 17)</span><span
|
|---|
| 7510 | class="cmtt-8"> vector</span><span
|
|---|
| 7511 | class="cmtt-8"> [floor1</span><span
|
|---|
| 7512 | class="cmtt-8">_step2</span><span
|
|---|
| 7513 | class="cmtt-8">_flag]</span><span
|
|---|
| 7514 | class="cmtt-8"> element</span><span
|
|---|
| 7515 | class="cmtt-8"> [low</span><span
|
|---|
| 7516 | class="cmtt-8">_neighbor</span><span
|
|---|
| 7517 | class="cmtt-8">_offset]</span><span
|
|---|
| 7518 | class="cmtt-8"> =</span><span
|
|---|
| 7519 | class="cmtt-8"> set</span>
|
|---|
| 7520 | <br class="fancyvrb" /><a
|
|---|
| 7521 | id="x1-103066r33"></a><span
|
|---|
| 7522 | class="cmr-6">33</span><span
|
|---|
| 7523 | class="cmtt-8"> </span><span
|
|---|
| 7524 | class="cmtt-8"> </span><span
|
|---|
| 7525 | class="cmtt-8"> </span><span
|
|---|
| 7526 | class="cmtt-8"> </span><span
|
|---|
| 7527 | class="cmtt-8"> </span><span
|
|---|
| 7528 | class="cmtt-8"> </span><span
|
|---|
| 7529 | class="cmtt-8"> </span><span
|
|---|
| 7530 | class="cmtt-8"> </span><span
|
|---|
| 7531 | class="cmtt-8"> </span><span
|
|---|
| 7532 | class="cmtt-8"> </span><span
|
|---|
| 7533 | class="cmtt-8"> </span><span
|
|---|
| 7534 | class="cmtt-8"> 18)</span><span
|
|---|
| 7535 | class="cmtt-8"> vector</span><span
|
|---|
| 7536 | class="cmtt-8"> [floor1</span><span
|
|---|
| 7537 | class="cmtt-8">_step2</span><span
|
|---|
| 7538 | class="cmtt-8">_flag]</span><span
|
|---|
| 7539 | class="cmtt-8"> element</span><span
|
|---|
| 7540 | class="cmtt-8"> [high</span><span
|
|---|
| 7541 | class="cmtt-8">_neighbor</span><span
|
|---|
| 7542 | class="cmtt-8">_offset]</span><span
|
|---|
| 7543 | class="cmtt-8"> =</span><span
|
|---|
| 7544 | class="cmtt-8"> set</span><br class="fancyvrb" /><a
|
|---|
| 7545 | id="x1-103068r34"></a><span
|
|---|
| 7546 | class="cmr-6">34</span><span
|
|---|
| 7547 | class="cmtt-8"> </span><span
|
|---|
| 7548 | class="cmtt-8"> </span><span
|
|---|
| 7549 | class="cmtt-8"> </span><span
|
|---|
| 7550 | class="cmtt-8"> </span><span
|
|---|
| 7551 | class="cmtt-8"> </span><span
|
|---|
| 7552 | class="cmtt-8"> </span><span
|
|---|
| 7553 | class="cmtt-8"> </span><span
|
|---|
| 7554 | class="cmtt-8"> </span><span
|
|---|
| 7555 | class="cmtt-8"> </span><span
|
|---|
| 7556 | class="cmtt-8"> </span><span
|
|---|
| 7557 | class="cmtt-8"> </span><span
|
|---|
| 7558 | class="cmtt-8"> 19)</span><span
|
|---|
| 7559 | class="cmtt-8"> vector</span><span
|
|---|
| 7560 | class="cmtt-8"> [floor1</span><span
|
|---|
| 7561 | class="cmtt-8">_step2</span><span
|
|---|
| 7562 | class="cmtt-8">_flag]</span><span
|
|---|
| 7563 | class="cmtt-8"> element</span><span
|
|---|
| 7564 | class="cmtt-8"> [i]</span><span
|
|---|
| 7565 | class="cmtt-8"> =</span><span
|
|---|
| 7566 | class="cmtt-8"> set</span>
|
|---|
| 7567 | <br class="fancyvrb" /><a
|
|---|
| 7568 | id="x1-103070r35"></a><span
|
|---|
| 7569 | class="cmr-6">35</span><span
|
|---|
| 7570 | class="cmtt-8"> </span><span
|
|---|
| 7571 | class="cmtt-8"> </span><span
|
|---|
| 7572 | class="cmtt-8"> </span><span
|
|---|
| 7573 | class="cmtt-8"> </span><span
|
|---|
| 7574 | class="cmtt-8"> </span><span
|
|---|
| 7575 | class="cmtt-8"> </span><span
|
|---|
| 7576 | class="cmtt-8"> </span><span
|
|---|
| 7577 | class="cmtt-8"> </span><span
|
|---|
| 7578 | class="cmtt-8"> </span><span
|
|---|
| 7579 | class="cmtt-8"> </span><span
|
|---|
| 7580 | class="cmtt-8"> </span><span
|
|---|
| 7581 | class="cmtt-8"> 20)</span><span
|
|---|
| 7582 | class="cmtt-8"> if</span><span
|
|---|
| 7583 | class="cmtt-8"> (</span><span
|
|---|
| 7584 | class="cmtt-8"> [val]</span><span
|
|---|
| 7585 | class="cmtt-8"> is</span><span
|
|---|
| 7586 | class="cmtt-8"> greater</span><span
|
|---|
| 7587 | class="cmtt-8"> than</span><span
|
|---|
| 7588 | class="cmtt-8"> or</span><span
|
|---|
| 7589 | class="cmtt-8"> equal</span><span
|
|---|
| 7590 | class="cmtt-8"> to</span><span
|
|---|
| 7591 | class="cmtt-8"> [room]</span><span
|
|---|
| 7592 | class="cmtt-8"> )</span><span
|
|---|
| 7593 | class="cmtt-8"> </span><span
|
|---|
| 7594 | class="cmsy-8">{</span><br class="fancyvrb" /><a
|
|---|
| 7595 | id="x1-103072r36"></a><span
|
|---|
| 7596 | class="cmr-6">36</span><br class="fancyvrb" /><a
|
|---|
| 7597 | id="x1-103074r37"></a><span
|
|---|
| 7598 | class="cmr-6">37</span><span
|
|---|
| 7599 | class="cmtt-8"> </span><span
|
|---|
| 7600 | class="cmtt-8"> </span><span
|
|---|
| 7601 | class="cmtt-8"> </span><span
|
|---|
| 7602 | class="cmtt-8"> </span><span
|
|---|
| 7603 | class="cmtt-8"> </span><span
|
|---|
| 7604 | class="cmtt-8"> </span><span
|
|---|
| 7605 | class="cmtt-8"> </span><span
|
|---|
| 7606 | class="cmtt-8"> </span><span
|
|---|
| 7607 | class="cmtt-8"> </span><span
|
|---|
| 7608 | class="cmtt-8"> </span><span
|
|---|
| 7609 | class="cmtt-8"> </span><span
|
|---|
| 7610 | class="cmtt-8"> </span><span
|
|---|
| 7611 | class="cmtt-8"> </span><span
|
|---|
| 7612 | class="cmtt-8"> </span><span
|
|---|
| 7613 | class="cmtt-8"> </span><span
|
|---|
| 7614 | class="cmtt-8"> </span><span
|
|---|
| 7615 | class="cmtt-8"> </span><span
|
|---|
| 7616 | class="cmtt-8"> 21)</span><span
|
|---|
| 7617 | class="cmtt-8"> if</span><span
|
|---|
| 7618 | class="cmtt-8"> (</span><span
|
|---|
| 7619 | class="cmtt-8"> [highroom]</span><span
|
|---|
| 7620 | class="cmtt-8"> is</span><span
|
|---|
| 7621 | class="cmtt-8"> greater</span><span
|
|---|
| 7622 | class="cmtt-8"> than</span><span
|
|---|
| 7623 | class="cmtt-8"> [lowroom]</span><span
|
|---|
| 7624 | class="cmtt-8"> )</span><span
|
|---|
| 7625 | class="cmtt-8"> </span><span
|
|---|
| 7626 | class="cmsy-8">{</span><br class="fancyvrb" /><a
|
|---|
| 7627 | id="x1-103076r38"></a><span
|
|---|
| 7628 | class="cmr-6">38</span>
|
|---|
| 7629 | <br class="fancyvrb" /><a
|
|---|
| 7630 | id="x1-103078r39"></a><span
|
|---|
| 7631 | class="cmr-6">39</span><span
|
|---|
| 7632 | class="cmtt-8"> </span><span
|
|---|
| 7633 | class="cmtt-8"> </span><span
|
|---|
| 7634 | class="cmtt-8"> </span><span
|
|---|
| 7635 | class="cmtt-8"> </span><span
|
|---|
| 7636 | class="cmtt-8"> </span><span
|
|---|
| 7637 | class="cmtt-8"> </span><span
|
|---|
| 7638 | class="cmtt-8"> </span><span
|
|---|
| 7639 | class="cmtt-8"> </span><span
|
|---|
| 7640 | class="cmtt-8"> </span><span
|
|---|
| 7641 | class="cmtt-8"> </span><span
|
|---|
| 7642 | class="cmtt-8"> </span><span
|
|---|
| 7643 | class="cmtt-8"> </span><span
|
|---|
| 7644 | class="cmtt-8"> </span><span
|
|---|
| 7645 | class="cmtt-8"> </span><span
|
|---|
| 7646 | class="cmtt-8"> </span><span
|
|---|
| 7647 | class="cmtt-8"> </span><span
|
|---|
| 7648 | class="cmtt-8"> </span><span
|
|---|
| 7649 | class="cmtt-8"> </span><span
|
|---|
| 7650 | class="cmtt-8"> </span><span
|
|---|
| 7651 | class="cmtt-8"> </span><span
|
|---|
| 7652 | class="cmtt-8"> </span><span
|
|---|
| 7653 | class="cmtt-8"> </span><span
|
|---|
| 7654 | class="cmtt-8"> </span><span
|
|---|
| 7655 | class="cmtt-8"> 22)</span><span
|
|---|
| 7656 | class="cmtt-8"> vector</span><span
|
|---|
| 7657 | class="cmtt-8"> [floor1</span><span
|
|---|
| 7658 | class="cmtt-8">_final</span><span
|
|---|
| 7659 | class="cmtt-8">_Y]</span><span
|
|---|
| 7660 | class="cmtt-8"> element</span><span
|
|---|
| 7661 | class="cmtt-8"> [i]</span><span
|
|---|
| 7662 | class="cmtt-8"> =</span><span
|
|---|
| 7663 | class="cmtt-8"> [val]</span><span
|
|---|
| 7664 | class="cmtt-8"> -</span><span
|
|---|
| 7665 | class="cmtt-8"> [lowroom]</span><span
|
|---|
| 7666 | class="cmtt-8"> +</span><span
|
|---|
| 7667 | class="cmtt-8"> [predicted]</span><br class="fancyvrb" /><a
|
|---|
| 7668 | id="x1-103080r40"></a><span
|
|---|
| 7669 | class="cmr-6">40</span>
|
|---|
| 7670 | <br class="fancyvrb" /><a
|
|---|
| 7671 | id="x1-103082r41"></a><span
|
|---|
| 7672 | class="cmr-6">41</span> <span
|
|---|
| 7673 | class="cmtt-8"> </span><span
|
|---|
| 7674 | class="cmtt-8"> </span><span
|
|---|
| 7675 | class="cmtt-8"> </span><span
|
|---|
| 7676 | class="cmtt-8"> </span><span
|
|---|
| 7677 | class="cmtt-8"> </span><span
|
|---|
| 7678 | class="cmtt-8"> </span><span
|
|---|
| 7679 | class="cmsy-8">}</span><span
|
|---|
| 7680 | class="cmtt-8"> else</span><span
|
|---|
| 7681 | class="cmtt-8"> [highroom]</span><span
|
|---|
| 7682 | class="cmtt-8"> is</span><span
|
|---|
| 7683 | class="cmtt-8"> not</span><span
|
|---|
| 7684 | class="cmtt-8"> greater</span><span
|
|---|
| 7685 | class="cmtt-8"> than</span><span
|
|---|
| 7686 | class="cmtt-8"> [lowroom]</span><span
|
|---|
| 7687 | class="cmtt-8"> </span><span
|
|---|
| 7688 | class="cmsy-8">{</span><br class="fancyvrb" /><a
|
|---|
| 7689 | id="x1-103084r42"></a><span
|
|---|
| 7690 | class="cmr-6">42</span>
|
|---|
| 7691 | <br class="fancyvrb" /><a
|
|---|
| 7692 | id="x1-103086r43"></a><span
|
|---|
| 7693 | class="cmr-6">43</span><span
|
|---|
| 7694 | class="cmtt-8"> </span><span
|
|---|
| 7695 | class="cmtt-8"> </span><span
|
|---|
| 7696 | class="cmtt-8"> </span><span
|
|---|
| 7697 | class="cmtt-8"> </span><span
|
|---|
| 7698 | class="cmtt-8"> </span><span
|
|---|
| 7699 | class="cmtt-8"> </span><span
|
|---|
| 7700 | class="cmtt-8"> </span><span
|
|---|
| 7701 | class="cmtt-8"> </span><span
|
|---|
| 7702 | class="cmtt-8"> </span><span
|
|---|
| 7703 | class="cmtt-8"> </span><span
|
|---|
| 7704 | class="cmtt-8"> </span><span
|
|---|
| 7705 | class="cmtt-8"> </span><span
|
|---|
| 7706 | class="cmtt-8"> </span><span
|
|---|
| 7707 | class="cmtt-8"> </span><span
|
|---|
| 7708 | class="cmtt-8"> </span><span
|
|---|
| 7709 | class="cmtt-8"> </span><span
|
|---|
| 7710 | class="cmtt-8"> </span><span
|
|---|
| 7711 | class="cmtt-8"> </span><span
|
|---|
| 7712 | class="cmtt-8"> </span><span
|
|---|
| 7713 | class="cmtt-8"> </span><span
|
|---|
| 7714 | class="cmtt-8"> </span><span
|
|---|
| 7715 | class="cmtt-8"> </span><span
|
|---|
| 7716 | class="cmtt-8"> </span><span
|
|---|
| 7717 | class="cmtt-8"> 23)</span><span
|
|---|
| 7718 | class="cmtt-8"> vector</span><span
|
|---|
| 7719 | class="cmtt-8"> [floor1</span><span
|
|---|
| 7720 | class="cmtt-8">_final</span><span
|
|---|
| 7721 | class="cmtt-8">_Y]</span><span
|
|---|
| 7722 | class="cmtt-8"> element</span><span
|
|---|
| 7723 | class="cmtt-8"> [i]</span><span
|
|---|
| 7724 | class="cmtt-8"> =</span><span
|
|---|
| 7725 | class="cmtt-8"> [predicted]</span><span
|
|---|
| 7726 | class="cmtt-8"> -</span><span
|
|---|
| 7727 | class="cmtt-8"> [val]</span><span
|
|---|
| 7728 | class="cmtt-8"> +</span><span
|
|---|
| 7729 | class="cmtt-8"> [highroom]</span><span
|
|---|
| 7730 | class="cmtt-8"> -</span><span
|
|---|
| 7731 | class="cmtt-8"> 1</span><br class="fancyvrb" /><a
|
|---|
| 7732 | id="x1-103088r44"></a><span
|
|---|
| 7733 | class="cmr-6">44</span>
|
|---|
| 7734 | <br class="fancyvrb" /><a
|
|---|
| 7735 | id="x1-103090r45"></a><span
|
|---|
| 7736 | class="cmr-6">45</span><span
|
|---|
| 7737 | class="cmtt-8"> </span><span
|
|---|
| 7738 | class="cmtt-8"> </span><span
|
|---|
| 7739 | class="cmtt-8"> </span><span
|
|---|
| 7740 | class="cmtt-8"> </span><span
|
|---|
| 7741 | class="cmtt-8"> </span><span
|
|---|
| 7742 | class="cmtt-8"> </span><span
|
|---|
| 7743 | class="cmtt-8"> </span><span
|
|---|
| 7744 | class="cmtt-8"> </span><span
|
|---|
| 7745 | class="cmtt-8"> </span><span
|
|---|
| 7746 | class="cmtt-8"> </span><span
|
|---|
| 7747 | class="cmtt-8"> </span><span
|
|---|
| 7748 | class="cmtt-8"> </span><span
|
|---|
| 7749 | class="cmtt-8"> </span><span
|
|---|
| 7750 | class="cmtt-8"> </span><span
|
|---|
| 7751 | class="cmtt-8"> </span><span
|
|---|
| 7752 | class="cmtt-8"> </span><span
|
|---|
| 7753 | class="cmtt-8"> </span><span
|
|---|
| 7754 | class="cmtt-8"> </span><span
|
|---|
| 7755 | class="cmtt-8"> </span><span
|
|---|
| 7756 | class="cmtt-8"> </span><span
|
|---|
| 7757 | class="cmtt-8"> </span><span
|
|---|
| 7758 | class="cmtt-8"> </span><span
|
|---|
| 7759 | class="cmsy-8">}</span><br class="fancyvrb" /><a
|
|---|
| 7760 | id="x1-103092r46"></a><span
|
|---|
| 7761 | class="cmr-6">46</span><br class="fancyvrb" /><a
|
|---|
| 7762 | id="x1-103094r47"></a><span
|
|---|
| 7763 | class="cmr-6">47</span><span
|
|---|
| 7764 | class="cmtt-8"> </span><span
|
|---|
| 7765 | class="cmtt-8"> </span><span
|
|---|
| 7766 | class="cmtt-8"> </span><span
|
|---|
| 7767 | class="cmtt-8"> </span><span
|
|---|
| 7768 | class="cmtt-8"> </span><span
|
|---|
| 7769 | class="cmtt-8"> </span><span
|
|---|
| 7770 | class="cmtt-8"> </span><span
|
|---|
| 7771 | class="cmtt-8"> </span><span
|
|---|
| 7772 | class="cmtt-8"> </span><span
|
|---|
| 7773 | class="cmtt-8"> </span><span
|
|---|
| 7774 | class="cmtt-8"> </span><span
|
|---|
| 7775 | class="cmtt-8"> </span><span
|
|---|
| 7776 | class="cmtt-8"> </span><span
|
|---|
| 7777 | class="cmtt-8"> </span><span
|
|---|
| 7778 | class="cmtt-8"> </span><span
|
|---|
| 7779 | class="cmtt-8"> </span><span
|
|---|
| 7780 | class="cmsy-8">}</span><span
|
|---|
| 7781 | class="cmtt-8"> else</span><span
|
|---|
| 7782 | class="cmtt-8"> [val]</span><span
|
|---|
| 7783 | class="cmtt-8"> is</span><span
|
|---|
| 7784 | class="cmtt-8"> less</span><span
|
|---|
| 7785 | class="cmtt-8"> than</span><span
|
|---|
| 7786 | class="cmtt-8"> [room]</span><span
|
|---|
| 7787 | class="cmtt-8"> </span><span
|
|---|
| 7788 | class="cmsy-8">{</span><br class="fancyvrb" /><a
|
|---|
| 7789 | id="x1-103096r48"></a><span
|
|---|
| 7790 | class="cmr-6">48</span>
|
|---|
| 7791 | <br class="fancyvrb" /><a
|
|---|
| 7792 | id="x1-103098r49"></a><span
|
|---|
| 7793 | class="cmr-6">49</span><span
|
|---|
| 7794 | class="cmtt-8"> </span><span
|
|---|
| 7795 | class="cmtt-8"> </span><span
|
|---|
| 7796 | class="cmtt-8"> </span><span
|
|---|
| 7797 | class="cmtt-8"> </span><span
|
|---|
| 7798 | class="cmtt-8"> </span><span
|
|---|
| 7799 | class="cmtt-8"> </span><span
|
|---|
| 7800 | class="cmtt-8"> </span><span
|
|---|
| 7801 | class="cmtt-8"> </span><span
|
|---|
| 7802 | class="cmtt-8"> </span><span
|
|---|
| 7803 | class="cmtt-8"> </span><span
|
|---|
| 7804 | class="cmtt-8"> </span><span
|
|---|
| 7805 | class="cmtt-8"> </span><span
|
|---|
| 7806 | class="cmtt-8"> </span><span
|
|---|
| 7807 | class="cmtt-8"> </span><span
|
|---|
| 7808 | class="cmtt-8"> </span><span
|
|---|
| 7809 | class="cmtt-8"> </span><span
|
|---|
| 7810 | class="cmtt-8"> </span><span
|
|---|
| 7811 | class="cmtt-8"> </span><span
|
|---|
| 7812 | class="cmtt-8"> </span><span
|
|---|
| 7813 | class="cmtt-8"> 24)</span><span
|
|---|
| 7814 | class="cmtt-8"> if</span><span
|
|---|
| 7815 | class="cmtt-8"> ([val]</span><span
|
|---|
| 7816 | class="cmtt-8"> is</span><span
|
|---|
| 7817 | class="cmtt-8"> odd)</span><span
|
|---|
| 7818 | class="cmtt-8"> </span><span
|
|---|
| 7819 | class="cmsy-8">{</span><br class="fancyvrb" /><a
|
|---|
| 7820 | id="x1-103100r50"></a><span
|
|---|
| 7821 | class="cmr-6">50</span><br class="fancyvrb" /><a
|
|---|
| 7822 | id="x1-103102r51"></a><span
|
|---|
| 7823 | class="cmr-6">51</span><span
|
|---|
| 7824 | class="cmtt-8"> </span><span
|
|---|
| 7825 | class="cmtt-8"> </span><span
|
|---|
| 7826 | class="cmtt-8"> </span><span
|
|---|
| 7827 | class="cmtt-8"> </span><span
|
|---|
| 7828 | class="cmtt-8"> </span><span
|
|---|
| 7829 | class="cmtt-8"> </span><span
|
|---|
| 7830 | class="cmtt-8"> </span><span
|
|---|
| 7831 | class="cmtt-8"> </span><span
|
|---|
| 7832 | class="cmtt-8"> </span><span
|
|---|
| 7833 | class="cmtt-8"> </span><span
|
|---|
| 7834 | class="cmtt-8"> </span><span
|
|---|
| 7835 | class="cmtt-8"> </span><span
|
|---|
| 7836 | class="cmtt-8"> </span><span
|
|---|
| 7837 | class="cmtt-8"> </span><span
|
|---|
| 7838 | class="cmtt-8"> </span><span
|
|---|
| 7839 | class="cmtt-8"> </span><span
|
|---|
| 7840 | class="cmtt-8"> </span><span
|
|---|
| 7841 | class="cmtt-8"> </span><span
|
|---|
| 7842 | class="cmtt-8"> </span><span
|
|---|
| 7843 | class="cmtt-8"> </span><span
|
|---|
| 7844 | class="cmtt-8"> </span><span
|
|---|
| 7845 | class="cmtt-8"> </span><span
|
|---|
| 7846 | class="cmtt-8"> </span><span
|
|---|
| 7847 | class="cmtt-8"> 25)</span><span
|
|---|
| 7848 | class="cmtt-8"> vector</span><span
|
|---|
| 7849 | class="cmtt-8"> [floor1</span><span
|
|---|
| 7850 | class="cmtt-8">_final</span><span
|
|---|
| 7851 | class="cmtt-8">_Y]</span><span
|
|---|
| 7852 | class="cmtt-8"> element</span><span
|
|---|
| 7853 | class="cmtt-8"> [i]</span><span
|
|---|
| 7854 | class="cmtt-8"> =</span>
|
|---|
| 7855 | <br class="fancyvrb" /><a
|
|---|
| 7856 | id="x1-103104r52"></a><span
|
|---|
| 7857 | class="cmr-6">52</span><span
|
|---|
| 7858 | class="cmtt-8"> </span><span
|
|---|
| 7859 | class="cmtt-8"> </span><span
|
|---|
| 7860 | class="cmtt-8"> </span><span
|
|---|
| 7861 | class="cmtt-8"> </span><span
|
|---|
| 7862 | class="cmtt-8"> </span><span
|
|---|
| 7863 | class="cmtt-8"> </span><span
|
|---|
| 7864 | class="cmtt-8"> </span><span
|
|---|
| 7865 | class="cmtt-8"> </span><span
|
|---|
| 7866 | class="cmtt-8"> </span><span
|
|---|
| 7867 | class="cmtt-8"> </span><span
|
|---|
| 7868 | class="cmtt-8"> </span><span
|
|---|
| 7869 | class="cmtt-8"> </span><span
|
|---|
| 7870 | class="cmtt-8"> </span><span
|
|---|
| 7871 | class="cmtt-8"> </span><span
|
|---|
| 7872 | class="cmtt-8"> </span><span
|
|---|
| 7873 | class="cmtt-8"> </span><span
|
|---|
| 7874 | class="cmtt-8"> </span><span
|
|---|
| 7875 | class="cmtt-8"> </span><span
|
|---|
| 7876 | class="cmtt-8"> </span><span
|
|---|
| 7877 | class="cmtt-8"> </span><span
|
|---|
| 7878 | class="cmtt-8"> </span><span
|
|---|
| 7879 | class="cmtt-8"> </span><span
|
|---|
| 7880 | class="cmtt-8"> </span><span
|
|---|
| 7881 | class="cmtt-8"> </span><span
|
|---|
| 7882 | class="cmtt-8"> </span><span
|
|---|
| 7883 | class="cmtt-8"> </span><span
|
|---|
| 7884 | class="cmtt-8"> </span><span
|
|---|
| 7885 | class="cmtt-8"> [predicted]</span><span
|
|---|
| 7886 | class="cmtt-8"> -</span><span
|
|---|
| 7887 | class="cmtt-8"> (([val]</span><span
|
|---|
| 7888 | class="cmtt-8"> +</span><span
|
|---|
| 7889 | class="cmtt-8"> 1)</span><span
|
|---|
| 7890 | class="cmtt-8"> divided</span><span
|
|---|
| 7891 | class="cmtt-8"> by</span><span
|
|---|
| 7892 | class="cmtt-8"> </span><span
|
|---|
| 7893 | class="cmtt-8"> 2</span><span
|
|---|
| 7894 | class="cmtt-8"> using</span><span
|
|---|
| 7895 | class="cmtt-8"> integer</span><span
|
|---|
| 7896 | class="cmtt-8"> division)</span><br class="fancyvrb" /><a
|
|---|
| 7897 | id="x1-103106r53"></a><span
|
|---|
| 7898 | class="cmr-6">53</span>
|
|---|
| 7899 | <br class="fancyvrb" /><a
|
|---|
| 7900 | id="x1-103108r54"></a><span
|
|---|
| 7901 | class="cmr-6">54</span><span
|
|---|
| 7902 | class="cmtt-8"> </span><span
|
|---|
| 7903 | class="cmtt-8"> </span><span
|
|---|
| 7904 | class="cmtt-8"> </span><span
|
|---|
| 7905 | class="cmtt-8"> </span><span
|
|---|
| 7906 | class="cmtt-8"> </span><span
|
|---|
| 7907 | class="cmtt-8"> </span><span
|
|---|
| 7908 | class="cmtt-8"> </span><span
|
|---|
| 7909 | class="cmtt-8"> </span><span
|
|---|
| 7910 | class="cmtt-8"> </span><span
|
|---|
| 7911 | class="cmtt-8"> </span><span
|
|---|
| 7912 | class="cmtt-8"> </span><span
|
|---|
| 7913 | class="cmtt-8"> </span><span
|
|---|
| 7914 | class="cmtt-8"> </span><span
|
|---|
| 7915 | class="cmtt-8"> </span><span
|
|---|
| 7916 | class="cmtt-8"> </span><span
|
|---|
| 7917 | class="cmtt-8"> </span><span
|
|---|
| 7918 | class="cmtt-8"> </span><span
|
|---|
| 7919 | class="cmtt-8"> </span><span
|
|---|
| 7920 | class="cmtt-8"> </span><span
|
|---|
| 7921 | class="cmtt-8"> </span><span
|
|---|
| 7922 | class="cmtt-8"> </span><span
|
|---|
| 7923 | class="cmtt-8"> </span><span
|
|---|
| 7924 | class="cmsy-8">}</span><span
|
|---|
| 7925 | class="cmtt-8"> else</span><span
|
|---|
| 7926 | class="cmtt-8"> [val]</span><span
|
|---|
| 7927 | class="cmtt-8"> is</span><span
|
|---|
| 7928 | class="cmtt-8"> even</span><span
|
|---|
| 7929 | class="cmtt-8"> </span><span
|
|---|
| 7930 | class="cmsy-8">{</span><br class="fancyvrb" /><a
|
|---|
| 7931 | id="x1-103110r55"></a><span
|
|---|
| 7932 | class="cmr-6">55</span><br class="fancyvrb" /><a
|
|---|
| 7933 | id="x1-103112r56"></a><span
|
|---|
| 7934 | class="cmr-6">56</span><span
|
|---|
| 7935 | class="cmtt-8"> </span><span
|
|---|
| 7936 | class="cmtt-8"> </span><span
|
|---|
| 7937 | class="cmtt-8"> </span><span
|
|---|
| 7938 | class="cmtt-8"> </span><span
|
|---|
| 7939 | class="cmtt-8"> </span><span
|
|---|
| 7940 | class="cmtt-8"> </span><span
|
|---|
| 7941 | class="cmtt-8"> </span><span
|
|---|
| 7942 | class="cmtt-8"> </span><span
|
|---|
| 7943 | class="cmtt-8"> </span><span
|
|---|
| 7944 | class="cmtt-8"> </span><span
|
|---|
| 7945 | class="cmtt-8"> </span><span
|
|---|
| 7946 | class="cmtt-8"> </span><span
|
|---|
| 7947 | class="cmtt-8"> </span><span
|
|---|
| 7948 | class="cmtt-8"> </span><span
|
|---|
| 7949 | class="cmtt-8"> </span><span
|
|---|
| 7950 | class="cmtt-8"> </span><span
|
|---|
| 7951 | class="cmtt-8"> </span><span
|
|---|
| 7952 | class="cmtt-8"> </span><span
|
|---|
| 7953 | class="cmtt-8"> </span><span
|
|---|
| 7954 | class="cmtt-8"> </span><span
|
|---|
| 7955 | class="cmtt-8"> </span><span
|
|---|
| 7956 | class="cmtt-8"> </span><span
|
|---|
| 7957 | class="cmtt-8"> </span><span
|
|---|
| 7958 | class="cmtt-8"> 26)</span><span
|
|---|
| 7959 | class="cmtt-8"> vector</span><span
|
|---|
| 7960 | class="cmtt-8"> [floor1</span><span
|
|---|
| 7961 | class="cmtt-8">_final</span><span
|
|---|
| 7962 | class="cmtt-8">_Y]</span><span
|
|---|
| 7963 | class="cmtt-8"> element</span><span
|
|---|
| 7964 | class="cmtt-8"> [i]</span><span
|
|---|
| 7965 | class="cmtt-8"> =</span>
|
|---|
| 7966 | <br class="fancyvrb" /><a
|
|---|
| 7967 | id="x1-103114r57"></a><span
|
|---|
| 7968 | class="cmr-6">57</span><span
|
|---|
| 7969 | class="cmtt-8"> </span><span
|
|---|
| 7970 | class="cmtt-8"> </span><span
|
|---|
| 7971 | class="cmtt-8"> </span><span
|
|---|
| 7972 | class="cmtt-8"> </span><span
|
|---|
| 7973 | class="cmtt-8"> </span><span
|
|---|
| 7974 | class="cmtt-8"> </span><span
|
|---|
| 7975 | class="cmtt-8"> </span><span
|
|---|
| 7976 | class="cmtt-8"> </span><span
|
|---|
| 7977 | class="cmtt-8"> </span><span
|
|---|
| 7978 | class="cmtt-8"> </span><span
|
|---|
| 7979 | class="cmtt-8"> </span><span
|
|---|
| 7980 | class="cmtt-8"> </span><span
|
|---|
| 7981 | class="cmtt-8"> </span><span
|
|---|
| 7982 | class="cmtt-8"> </span><span
|
|---|
| 7983 | class="cmtt-8"> </span><span
|
|---|
| 7984 | class="cmtt-8"> </span><span
|
|---|
| 7985 | class="cmtt-8"> </span><span
|
|---|
| 7986 | class="cmtt-8"> </span><span
|
|---|
| 7987 | class="cmtt-8"> </span><span
|
|---|
| 7988 | class="cmtt-8"> </span><span
|
|---|
| 7989 | class="cmtt-8"> </span><span
|
|---|
| 7990 | class="cmtt-8"> </span><span
|
|---|
| 7991 | class="cmtt-8"> </span><span
|
|---|
| 7992 | class="cmtt-8"> </span><span
|
|---|
| 7993 | class="cmtt-8"> </span><span
|
|---|
| 7994 | class="cmtt-8"> </span><span
|
|---|
| 7995 | class="cmtt-8"> </span><span
|
|---|
| 7996 | class="cmtt-8"> [predicted]</span><span
|
|---|
| 7997 | class="cmtt-8"> +</span><span
|
|---|
| 7998 | class="cmtt-8"> ([val]</span><span
|
|---|
| 7999 | class="cmtt-8"> /</span><span
|
|---|
| 8000 | class="cmtt-8"> 2</span><span
|
|---|
| 8001 | class="cmtt-8"> using</span><span
|
|---|
| 8002 | class="cmtt-8"> integer</span><span
|
|---|
| 8003 | class="cmtt-8"> division)</span><br class="fancyvrb" /><a
|
|---|
| 8004 | id="x1-103116r58"></a><span
|
|---|
| 8005 | class="cmr-6">58</span><br class="fancyvrb" /><a
|
|---|
| 8006 | id="x1-103118r59"></a><span
|
|---|
| 8007 | class="cmr-6">59</span><span
|
|---|
| 8008 | class="cmtt-8"> </span><span
|
|---|
| 8009 | class="cmtt-8"> </span><span
|
|---|
| 8010 | class="cmtt-8"> </span><span
|
|---|
| 8011 | class="cmtt-8"> </span><span
|
|---|
| 8012 | class="cmtt-8"> </span><span
|
|---|
| 8013 | class="cmtt-8"> </span><span
|
|---|
| 8014 | class="cmtt-8"> </span><span
|
|---|
| 8015 | class="cmtt-8"> </span><span
|
|---|
| 8016 | class="cmtt-8"> </span><span
|
|---|
| 8017 | class="cmtt-8"> </span><span
|
|---|
| 8018 | class="cmtt-8"> </span><span
|
|---|
| 8019 | class="cmtt-8"> </span><span
|
|---|
| 8020 | class="cmtt-8"> </span><span
|
|---|
| 8021 | class="cmtt-8"> </span><span
|
|---|
| 8022 | class="cmtt-8"> </span><span
|
|---|
| 8023 | class="cmtt-8"> </span><span
|
|---|
| 8024 | class="cmtt-8"> </span><span
|
|---|
| 8025 | class="cmtt-8"> </span><span
|
|---|
| 8026 | class="cmtt-8"> </span><span
|
|---|
| 8027 | class="cmtt-8"> </span><span
|
|---|
| 8028 | class="cmtt-8"> </span><span
|
|---|
| 8029 | class="cmtt-8"> </span><span
|
|---|
| 8030 | class="cmsy-8">}</span><br class="fancyvrb" /><a
|
|---|
| 8031 | id="x1-103120r60"></a><span
|
|---|
| 8032 | class="cmr-6">60</span>
|
|---|
| 8033 | <br class="fancyvrb" /><a
|
|---|
| 8034 | id="x1-103122r61"></a><span
|
|---|
| 8035 | class="cmr-6">61</span><span
|
|---|
| 8036 | class="cmtt-8"> </span><span
|
|---|
| 8037 | class="cmtt-8"> </span><span
|
|---|
| 8038 | class="cmtt-8"> </span><span
|
|---|
| 8039 | class="cmtt-8"> </span><span
|
|---|
| 8040 | class="cmtt-8"> </span><span
|
|---|
| 8041 | class="cmtt-8"> </span><span
|
|---|
| 8042 | class="cmtt-8"> </span><span
|
|---|
| 8043 | class="cmtt-8"> </span><span
|
|---|
| 8044 | class="cmtt-8"> </span><span
|
|---|
| 8045 | class="cmtt-8"> </span><span
|
|---|
| 8046 | class="cmtt-8"> </span><span
|
|---|
| 8047 | class="cmtt-8"> </span><span
|
|---|
| 8048 | class="cmtt-8"> </span><span
|
|---|
| 8049 | class="cmtt-8"> </span><span
|
|---|
| 8050 | class="cmtt-8"> </span><span
|
|---|
| 8051 | class="cmtt-8"> </span><span
|
|---|
| 8052 | class="cmsy-8">}</span><br class="fancyvrb" /><a
|
|---|
| 8053 | id="x1-103124r62"></a><span
|
|---|
| 8054 | class="cmr-6">62</span><br class="fancyvrb" /><a
|
|---|
| 8055 | id="x1-103126r63"></a><span
|
|---|
| 8056 | class="cmr-6">63</span><span
|
|---|
| 8057 | class="cmtt-8"> </span><span
|
|---|
| 8058 | class="cmtt-8"> </span><span
|
|---|
| 8059 | class="cmtt-8"> </span><span
|
|---|
| 8060 | class="cmtt-8"> </span><span
|
|---|
| 8061 | class="cmtt-8"> </span><span
|
|---|
| 8062 | class="cmtt-8"> </span><span
|
|---|
| 8063 | class="cmtt-8"> </span><span
|
|---|
| 8064 | class="cmtt-8"> </span><span
|
|---|
| 8065 | class="cmtt-8"> </span><span
|
|---|
| 8066 | class="cmtt-8"> </span><span
|
|---|
| 8067 | class="cmsy-8">}</span><span
|
|---|
| 8068 | class="cmtt-8"> else</span><span
|
|---|
| 8069 | class="cmtt-8"> [val]</span><span
|
|---|
| 8070 | class="cmtt-8"> is</span><span
|
|---|
| 8071 | class="cmtt-8"> zero</span><span
|
|---|
| 8072 | class="cmtt-8"> </span><span
|
|---|
| 8073 | class="cmsy-8">{</span><br class="fancyvrb" /><a
|
|---|
| 8074 | id="x1-103128r64"></a><span
|
|---|
| 8075 | class="cmr-6">64</span><br class="fancyvrb" /><a
|
|---|
| 8076 | id="x1-103130r65"></a><span
|
|---|
| 8077 | class="cmr-6">65</span><span
|
|---|
| 8078 | class="cmtt-8"> </span><span
|
|---|
| 8079 | class="cmtt-8"> </span><span
|
|---|
| 8080 | class="cmtt-8"> </span><span
|
|---|
| 8081 | class="cmtt-8"> </span><span
|
|---|
| 8082 | class="cmtt-8"> </span><span
|
|---|
| 8083 | class="cmtt-8"> </span><span
|
|---|
| 8084 | class="cmtt-8"> </span><span
|
|---|
| 8085 | class="cmtt-8"> </span><span
|
|---|
| 8086 | class="cmtt-8"> </span><span
|
|---|
| 8087 | class="cmtt-8"> </span><span
|
|---|
| 8088 | class="cmtt-8"> </span><span
|
|---|
| 8089 | class="cmtt-8"> 27)</span><span
|
|---|
| 8090 | class="cmtt-8"> vector</span><span
|
|---|
| 8091 | class="cmtt-8"> [floor1</span><span
|
|---|
| 8092 | class="cmtt-8">_step2</span><span
|
|---|
| 8093 | class="cmtt-8">_flag]</span><span
|
|---|
| 8094 | class="cmtt-8"> element</span><span
|
|---|
| 8095 | class="cmtt-8"> [i]</span><span
|
|---|
| 8096 | class="cmtt-8"> =</span><span
|
|---|
| 8097 | class="cmtt-8"> unset</span>
|
|---|
| 8098 | <br class="fancyvrb" /><a
|
|---|
| 8099 | id="x1-103132r66"></a><span
|
|---|
| 8100 | class="cmr-6">66</span><span
|
|---|
| 8101 | class="cmtt-8"> </span><span
|
|---|
| 8102 | class="cmtt-8"> </span><span
|
|---|
| 8103 | class="cmtt-8"> </span><span
|
|---|
| 8104 | class="cmtt-8"> </span><span
|
|---|
| 8105 | class="cmtt-8"> </span><span
|
|---|
| 8106 | class="cmtt-8"> </span><span
|
|---|
| 8107 | class="cmtt-8"> </span><span
|
|---|
| 8108 | class="cmtt-8"> </span><span
|
|---|
| 8109 | class="cmtt-8"> </span><span
|
|---|
| 8110 | class="cmtt-8"> </span><span
|
|---|
| 8111 | class="cmtt-8"> </span><span
|
|---|
| 8112 | class="cmtt-8"> 28)</span><span
|
|---|
| 8113 | class="cmtt-8"> vector</span><span
|
|---|
| 8114 | class="cmtt-8"> [floor1</span><span
|
|---|
| 8115 | class="cmtt-8">_final</span><span
|
|---|
| 8116 | class="cmtt-8">_Y]</span><span
|
|---|
| 8117 | class="cmtt-8"> element</span><span
|
|---|
| 8118 | class="cmtt-8"> [i]</span><span
|
|---|
| 8119 | class="cmtt-8"> =</span><span
|
|---|
| 8120 | class="cmtt-8"> [predicted]</span><br class="fancyvrb" /><a
|
|---|
| 8121 | id="x1-103134r67"></a><span
|
|---|
| 8122 | class="cmr-6">67</span><br class="fancyvrb" /><a
|
|---|
| 8123 | id="x1-103136r68"></a><span
|
|---|
| 8124 | class="cmr-6">68</span><span
|
|---|
| 8125 | class="cmtt-8"> </span><span
|
|---|
| 8126 | class="cmtt-8"> </span><span
|
|---|
| 8127 | class="cmtt-8"> </span><span
|
|---|
| 8128 | class="cmtt-8"> </span><span
|
|---|
| 8129 | class="cmtt-8"> </span><span
|
|---|
| 8130 | class="cmtt-8"> </span><span
|
|---|
| 8131 | class="cmtt-8"> </span><span
|
|---|
| 8132 | class="cmtt-8"> </span><span
|
|---|
| 8133 | class="cmtt-8"> </span><span
|
|---|
| 8134 | class="cmtt-8"> </span><span
|
|---|
| 8135 | class="cmsy-8">}</span><br class="fancyvrb" /><a
|
|---|
| 8136 | id="x1-103138r69"></a><span
|
|---|
| 8137 | class="cmr-6">69</span><br class="fancyvrb" /><a
|
|---|
| 8138 | id="x1-103140r70"></a><span
|
|---|
| 8139 | class="cmr-6">70</span><span
|
|---|
| 8140 | class="cmtt-8"> </span><span
|
|---|
| 8141 | class="cmtt-8"> </span><span
|
|---|
| 8142 | class="cmtt-8"> </span><span
|
|---|
| 8143 | class="cmtt-8"> </span><span
|
|---|
| 8144 | class="cmtt-8"> </span><span
|
|---|
| 8145 | class="cmsy-8">}</span><br class="fancyvrb" /><a
|
|---|
| 8146 | id="x1-103142r71"></a><span
|
|---|
| 8147 | class="cmr-6">71</span><br class="fancyvrb" /><a
|
|---|
| 8148 | id="x1-103144r72"></a><span
|
|---|
| 8149 | class="cmr-6">72</span><span
|
|---|
| 8150 | class="cmtt-8"> 29)</span><span
|
|---|
| 8151 | class="cmtt-8"> done</span><br class="fancyvrb" /><a
|
|---|
| 8152 | id="x1-103146r73"></a><span
|
|---|
| 8153 | class="cmr-6">73</span></div>
|
|---|
| 8154 | </dd><dt class="description">
|
|---|
| 8155 | <span
|
|---|
| 8156 | class="cmssbx-10x-x-120">step 2: curve synthesis</span> </dt><dd
|
|---|
| 8157 | class="description">
|
|---|
| 8158 | <!--l. 350--><p class="noindent" >Curve synthesis generates a return vector <span
|
|---|
| 8159 | class="cmtt-12">[floor] </span>of length <span
|
|---|
| 8160 | class="cmtt-12">[n] </span>(where <span
|
|---|
| 8161 | class="cmtt-12">[n] </span>is provided by
|
|---|
| 8162 | the decode process calling to floor decode). Floor 1 curve synthesis makes use of the
|
|---|
| 8163 | <span
|
|---|
| 8164 | class="cmtt-12">[floor1</span><span
|
|---|
| 8165 | class="cmtt-12">_X</span><span
|
|---|
| 8166 | class="cmtt-12">_list]</span>, <span
|
|---|
| 8167 | class="cmtt-12">[floor1</span><span
|
|---|
| 8168 | class="cmtt-12">_final</span><span
|
|---|
| 8169 | class="cmtt-12">_Y] </span>and <span
|
|---|
| 8170 | class="cmtt-12">[floor1</span><span
|
|---|
| 8171 | class="cmtt-12">_step2</span><span
|
|---|
| 8172 | class="cmtt-12">_flag] </span>vectors, as well as
|
|---|
| 8173 | [floor1_multiplier] and [floor1_values] values.
|
|---|
| 8174 | <!--l. 357--><p class="noindent" >Decode begins by sorting the scalars from vectors <span
|
|---|
| 8175 | class="cmtt-12">[floor1</span><span
|
|---|
| 8176 | class="cmtt-12">_X</span><span
|
|---|
| 8177 | class="cmtt-12">_list]</span>, <span
|
|---|
| 8178 | class="cmtt-12">[floor1</span><span
|
|---|
| 8179 | class="cmtt-12">_final</span><span
|
|---|
| 8180 | class="cmtt-12">_Y] </span>and
|
|---|
| 8181 | <span
|
|---|
| 8182 | class="cmtt-12">[floor1</span><span
|
|---|
| 8183 | class="cmtt-12">_step2</span><span
|
|---|
| 8184 | class="cmtt-12">_flag] </span>together into new vectors <span
|
|---|
| 8185 | class="cmtt-12">[floor1</span><span
|
|---|
| 8186 | class="cmtt-12">_X</span><span
|
|---|
| 8187 | class="cmtt-12">_list]’</span>, <span
|
|---|
| 8188 | class="cmtt-12">[floor1</span><span
|
|---|
| 8189 | class="cmtt-12">_final</span><span
|
|---|
| 8190 | class="cmtt-12">_Y]’</span>
|
|---|
| 8191 | and <span
|
|---|
| 8192 | class="cmtt-12">[floor1</span><span
|
|---|
| 8193 | class="cmtt-12">_step2</span><span
|
|---|
| 8194 | class="cmtt-12">_flag]’ </span>according to ascending sort order of the values in
|
|---|
| 8195 | <span
|
|---|
| 8196 | class="cmtt-12">[floor1</span><span
|
|---|
| 8197 | class="cmtt-12">_X</span><span
|
|---|
| 8198 | class="cmtt-12">_list]</span>. That is, sort the values of <span
|
|---|
| 8199 | class="cmtt-12">[floor1</span><span
|
|---|
| 8200 | class="cmtt-12">_X</span><span
|
|---|
| 8201 | class="cmtt-12">_list] </span>and then apply the same
|
|---|
| 8202 | permutation to elements of the other two vectors so that the X, Y and step2_flag values
|
|---|
| 8203 | still match.
|
|---|
| 8204 | <!--l. 367--><p class="noindent" >Then compute the final curve in one pass:
|
|---|
| 8205 | <!--l. 369--><p class="noindent" >
|
|---|
| 8206 | <div class="fancyvrb" id="fancyvrb32"><a
|
|---|
| 8207 | id="x1-103148r1"></a><span
|
|---|
| 8208 | class="cmr-6">1</span><span
|
|---|
| 8209 | class="cmtt-8"> </span><span
|
|---|
| 8210 | class="cmtt-8"> 1)</span><span
|
|---|
| 8211 | class="cmtt-8"> [hx]</span><span
|
|---|
| 8212 | class="cmtt-8"> =</span><span
|
|---|
| 8213 | class="cmtt-8"> 0</span><br class="fancyvrb" /><a
|
|---|
| 8214 | id="x1-103150r2"></a><span
|
|---|
| 8215 | class="cmr-6">2</span><span
|
|---|
| 8216 | class="cmtt-8"> </span><span
|
|---|
| 8217 | class="cmtt-8"> 2)</span><span
|
|---|
| 8218 | class="cmtt-8"> [lx]</span><span
|
|---|
| 8219 | class="cmtt-8"> =</span><span
|
|---|
| 8220 | class="cmtt-8"> 0</span><br class="fancyvrb" /><a
|
|---|
| 8221 | id="x1-103152r3"></a><span
|
|---|
| 8222 | class="cmr-6">3</span><span
|
|---|
| 8223 | class="cmtt-8"> </span><span
|
|---|
| 8224 | class="cmtt-8"> 3)</span><span
|
|---|
| 8225 | class="cmtt-8"> [ly]</span><span
|
|---|
| 8226 | class="cmtt-8"> =</span><span
|
|---|
| 8227 | class="cmtt-8"> vector</span><span
|
|---|
| 8228 | class="cmtt-8"> [floor1</span><span
|
|---|
| 8229 | class="cmtt-8">_final</span><span
|
|---|
| 8230 | class="cmtt-8">_Y]’</span><span
|
|---|
| 8231 | class="cmtt-8"> element</span><span
|
|---|
| 8232 | class="cmtt-8"> [0]</span><span
|
|---|
| 8233 | class="cmtt-8"> *</span><span
|
|---|
| 8234 | class="cmtt-8"> [floor1</span><span
|
|---|
| 8235 | class="cmtt-8">_multiplier]</span>
|
|---|
| 8236 | <br class="fancyvrb" /><a
|
|---|
| 8237 | id="x1-103154r4"></a><span
|
|---|
| 8238 | class="cmr-6">4</span><span
|
|---|
| 8239 | class="cmtt-8"> </span><span
|
|---|
| 8240 | class="cmtt-8"> 4)</span><span
|
|---|
| 8241 | class="cmtt-8"> iterate</span><span
|
|---|
| 8242 | class="cmtt-8"> [i]</span><span
|
|---|
| 8243 | class="cmtt-8"> over</span><span
|
|---|
| 8244 | class="cmtt-8"> the</span><span
|
|---|
| 8245 | class="cmtt-8"> range</span><span
|
|---|
| 8246 | class="cmtt-8"> 1</span><span
|
|---|
| 8247 | class="cmtt-8"> ...</span><span
|
|---|
| 8248 | class="cmtt-8"> [floor1</span><span
|
|---|
| 8249 | class="cmtt-8">_values]-1</span><span
|
|---|
| 8250 | class="cmtt-8"> </span><span
|
|---|
| 8251 | class="cmsy-8">{</span><br class="fancyvrb" /><a
|
|---|
| 8252 | id="x1-103156r5"></a><span
|
|---|
| 8253 | class="cmr-6">5</span><br class="fancyvrb" /><a
|
|---|
| 8254 | id="x1-103158r6"></a><span
|
|---|
| 8255 | class="cmr-6">6</span><span
|
|---|
| 8256 | class="cmtt-8"> </span><span
|
|---|
| 8257 | class="cmtt-8"> </span><span
|
|---|
| 8258 | class="cmtt-8"> </span><span
|
|---|
| 8259 | class="cmtt-8"> </span><span
|
|---|
| 8260 | class="cmtt-8"> </span><span
|
|---|
| 8261 | class="cmtt-8"> </span><span
|
|---|
| 8262 | class="cmtt-8"> 5)</span><span
|
|---|
| 8263 | class="cmtt-8"> if</span><span
|
|---|
| 8264 | class="cmtt-8"> (</span><span
|
|---|
| 8265 | class="cmtt-8"> [floor1</span><span
|
|---|
| 8266 | class="cmtt-8">_step2</span><span
|
|---|
| 8267 | class="cmtt-8">_flag]’</span><span
|
|---|
| 8268 | class="cmtt-8"> element</span><span
|
|---|
| 8269 | class="cmtt-8"> [i]</span><span
|
|---|
| 8270 | class="cmtt-8"> is</span><span
|
|---|
| 8271 | class="cmtt-8"> set</span><span
|
|---|
| 8272 | class="cmtt-8"> )</span><span
|
|---|
| 8273 | class="cmtt-8"> </span><span
|
|---|
| 8274 | class="cmsy-8">{</span><br class="fancyvrb" /><a
|
|---|
| 8275 | id="x1-103160r7"></a><span
|
|---|
| 8276 | class="cmr-6">7</span>
|
|---|
| 8277 | <br class="fancyvrb" /><a
|
|---|
| 8278 | id="x1-103162r8"></a><span
|
|---|
| 8279 | class="cmr-6">8</span><span
|
|---|
| 8280 | class="cmtt-8"> </span><span
|
|---|
| 8281 | class="cmtt-8"> </span><span
|
|---|
| 8282 | class="cmtt-8"> </span><span
|
|---|
| 8283 | class="cmtt-8"> </span><span
|
|---|
| 8284 | class="cmtt-8"> </span><span
|
|---|
| 8285 | class="cmtt-8"> </span><span
|
|---|
| 8286 | class="cmtt-8"> </span><span
|
|---|
| 8287 | class="cmtt-8"> </span><span
|
|---|
| 8288 | class="cmtt-8"> </span><span
|
|---|
| 8289 | class="cmtt-8"> </span><span
|
|---|
| 8290 | class="cmtt-8"> </span><span
|
|---|
| 8291 | class="cmtt-8"> </span><span
|
|---|
| 8292 | class="cmtt-8"> 6)</span><span
|
|---|
| 8293 | class="cmtt-8"> [hy]</span><span
|
|---|
| 8294 | class="cmtt-8"> =</span><span
|
|---|
| 8295 | class="cmtt-8"> [floor1</span><span
|
|---|
| 8296 | class="cmtt-8">_final</span><span
|
|---|
| 8297 | class="cmtt-8">_Y]’</span><span
|
|---|
| 8298 | class="cmtt-8"> element</span><span
|
|---|
| 8299 | class="cmtt-8"> [i]</span><span
|
|---|
| 8300 | class="cmtt-8"> *</span><span
|
|---|
| 8301 | class="cmtt-8"> [floor1</span><span
|
|---|
| 8302 | class="cmtt-8">_multiplier]</span><br class="fancyvrb" /><a
|
|---|
| 8303 | id="x1-103164r9"></a><span
|
|---|
| 8304 | class="cmr-6">9</span><span
|
|---|
| 8305 | class="cmtt-8">  </span><span
|
|---|
| 8306 | class="cmtt-8"> </span><span
|
|---|
| 8307 | class="cmtt-8"> </span><span
|
|---|
| 8308 | class="cmtt-8"> </span><span
|
|---|
| 8309 | class="cmtt-8"> </span><span
|
|---|
| 8310 | class="cmtt-8"> 7)</span><span
|
|---|
| 8311 | class="cmtt-8"> [hx]</span><span
|
|---|
| 8312 | class="cmtt-8"> =</span><span
|
|---|
| 8313 | class="cmtt-8"> [floor1</span><span
|
|---|
| 8314 | class="cmtt-8">_X</span><span
|
|---|
| 8315 | class="cmtt-8">_list]’</span><span
|
|---|
| 8316 | class="cmtt-8"> element</span><span
|
|---|
| 8317 | class="cmtt-8"> [i]</span>
|
|---|
| 8318 | <br class="fancyvrb" /><a
|
|---|
| 8319 | id="x1-103166r10"></a><span
|
|---|
| 8320 | class="cmr-6">10</span><span
|
|---|
| 8321 | class="cmtt-8"> </span><span
|
|---|
| 8322 | class="cmtt-8"> </span><span
|
|---|
| 8323 | class="cmtt-8"> </span><span
|
|---|
| 8324 | class="cmtt-8"> </span><span
|
|---|
| 8325 | class="cmtt-8"> </span><span
|
|---|
| 8326 | class="cmtt-8"> </span><span
|
|---|
| 8327 | class="cmtt-8"> </span><span
|
|---|
| 8328 | class="cmtt-8"> </span><span
|
|---|
| 8329 | class="cmtt-8"> </span><span
|
|---|
| 8330 | class="cmtt-8"> </span><span
|
|---|
| 8331 | class="cmtt-8"> </span><span
|
|---|
| 8332 | class="cmtt-8"> </span><span
|
|---|
| 8333 | class="cmtt-8"> 8)</span><span
|
|---|
| 8334 | class="cmtt-8"> </span><a
|
|---|
| 8335 | href="#x1-1250009.2.7"><span
|
|---|
| 8336 | class="cmtt-8">render</span><span
|
|---|
| 8337 | class="cmtt-8">_line</span></a><span
|
|---|
| 8338 | class="cmtt-8">(</span><span
|
|---|
| 8339 | class="cmtt-8"> [lx],</span><span
|
|---|
| 8340 | class="cmtt-8"> [ly],</span><span
|
|---|
| 8341 | class="cmtt-8"> [hx],</span><span
|
|---|
| 8342 | class="cmtt-8"> [hy],</span><span
|
|---|
| 8343 | class="cmtt-8"> [floor]</span><span
|
|---|
| 8344 | class="cmtt-8"> )</span><br class="fancyvrb" /><a
|
|---|
| 8345 | id="x1-103168r11"></a><span
|
|---|
| 8346 | class="cmr-6">11</span><span
|
|---|
| 8347 | class="cmtt-8"> </span><span
|
|---|
| 8348 | class="cmtt-8"> </span><span
|
|---|
| 8349 | class="cmtt-8"> </span><span
|
|---|
| 8350 | class="cmtt-8"> </span><span
|
|---|
| 8351 | class="cmtt-8"> </span><span
|
|---|
| 8352 | class="cmtt-8"> </span><span
|
|---|
| 8353 | class="cmtt-8"> </span><span
|
|---|
| 8354 | class="cmtt-8"> </span><span
|
|---|
| 8355 | class="cmtt-8"> </span><span
|
|---|
| 8356 | class="cmtt-8"> </span><span
|
|---|
| 8357 | class="cmtt-8"> </span><span
|
|---|
| 8358 | class="cmtt-8"> </span><span
|
|---|
| 8359 | class="cmtt-8"> 9)</span><span
|
|---|
| 8360 | class="cmtt-8"> [lx]</span><span
|
|---|
| 8361 | class="cmtt-8"> =</span><span
|
|---|
| 8362 | class="cmtt-8"> [hx]</span><br class="fancyvrb" /><a
|
|---|
| 8363 | id="x1-103170r12"></a><span
|
|---|
| 8364 | class="cmr-6">12</span> <span
|
|---|
| 8365 | class="cmtt-8"> </span><span
|
|---|
| 8366 | class="cmtt-8"> </span><span
|
|---|
| 8367 | class="cmtt-8"> </span><span
|
|---|
| 8368 | class="cmtt-8"> 10)</span><span
|
|---|
| 8369 | class="cmtt-8"> [ly]</span><span
|
|---|
| 8370 | class="cmtt-8"> =</span><span
|
|---|
| 8371 | class="cmtt-8"> [hy]</span><br class="fancyvrb" /><a
|
|---|
| 8372 | id="x1-103172r13"></a><span
|
|---|
| 8373 | class="cmr-6">13</span><span
|
|---|
| 8374 | class="cmtt-8"> </span><span
|
|---|
| 8375 | class="cmtt-8"> </span><span
|
|---|
| 8376 | class="cmtt-8"> </span><span
|
|---|
| 8377 | class="cmtt-8"> </span><span
|
|---|
| 8378 | class="cmtt-8"> </span><span
|
|---|
| 8379 | class="cmtt-8"> </span><span
|
|---|
| 8380 | class="cmtt-8"> </span><span
|
|---|
| 8381 | class="cmtt-8"> </span><span
|
|---|
| 8382 | class="cmtt-8"> </span><span
|
|---|
| 8383 | class="cmtt-8"> </span><span
|
|---|
| 8384 | class="cmsy-8">}</span><br class="fancyvrb" /><a
|
|---|
| 8385 | id="x1-103174r14"></a><span
|
|---|
| 8386 | class="cmr-6">14</span><span
|
|---|
| 8387 | class="cmtt-8"> </span><span
|
|---|
| 8388 | class="cmtt-8"> </span><span
|
|---|
| 8389 | class="cmtt-8"> </span><span
|
|---|
| 8390 | class="cmtt-8"> </span><span
|
|---|
| 8391 | class="cmtt-8"> </span><span
|
|---|
| 8392 | class="cmsy-8">}</span><br class="fancyvrb" /><a
|
|---|
| 8393 | id="x1-103176r15"></a><span
|
|---|
| 8394 | class="cmr-6">15</span>
|
|---|
| 8395 | <br class="fancyvrb" /><a
|
|---|
| 8396 | id="x1-103178r16"></a><span
|
|---|
| 8397 | class="cmr-6">16</span><span
|
|---|
| 8398 | class="cmtt-8"> 11)</span><span
|
|---|
| 8399 | class="cmtt-8"> if</span><span
|
|---|
| 8400 | class="cmtt-8"> (</span><span
|
|---|
| 8401 | class="cmtt-8"> [hx]</span><span
|
|---|
| 8402 | class="cmtt-8"> is</span><span
|
|---|
| 8403 | class="cmtt-8"> less</span><span
|
|---|
| 8404 | class="cmtt-8"> than</span><span
|
|---|
| 8405 | class="cmtt-8"> [n]</span><span
|
|---|
| 8406 | class="cmtt-8"> )</span><span
|
|---|
| 8407 | class="cmtt-8"> </span><span
|
|---|
| 8408 | class="cmsy-8">{</span><br class="fancyvrb" /><a
|
|---|
| 8409 | id="x1-103180r17"></a><span
|
|---|
| 8410 | class="cmr-6">17</span><br class="fancyvrb" /><a
|
|---|
| 8411 | id="x1-103182r18"></a><span
|
|---|
| 8412 | class="cmr-6">18</span><span
|
|---|
| 8413 | class="cmtt-8"> </span><span
|
|---|
| 8414 | class="cmtt-8"> </span><span
|
|---|
| 8415 | class="cmtt-8"> </span><span
|
|---|
| 8416 | class="cmtt-8"> </span><span
|
|---|
| 8417 | class="cmtt-8"> </span><span
|
|---|
| 8418 | class="cmtt-8"> </span><span
|
|---|
| 8419 | class="cmtt-8"> </span><span
|
|---|
| 8420 | class="cmtt-8"> 12)</span><span
|
|---|
| 8421 | class="cmtt-8"> </span><a
|
|---|
| 8422 | href="#x1-1250009.2.7"><span
|
|---|
| 8423 | class="cmtt-8">render</span><span
|
|---|
| 8424 | class="cmtt-8">_line</span></a><span
|
|---|
| 8425 | class="cmtt-8">(</span><span
|
|---|
| 8426 | class="cmtt-8"> [hx],</span><span
|
|---|
| 8427 | class="cmtt-8"> [hy],</span><span
|
|---|
| 8428 | class="cmtt-8"> [n],</span><span
|
|---|
| 8429 | class="cmtt-8"> [hy],</span><span
|
|---|
| 8430 | class="cmtt-8"> [floor]</span><span
|
|---|
| 8431 | class="cmtt-8"> )</span><br class="fancyvrb" /><a
|
|---|
| 8432 | id="x1-103184r19"></a><span
|
|---|
| 8433 | class="cmr-6">19</span><br class="fancyvrb" /><a
|
|---|
| 8434 | id="x1-103186r20"></a><span
|
|---|
| 8435 | class="cmr-6">20</span><span
|
|---|
| 8436 | class="cmtt-8"> </span><span
|
|---|
| 8437 | class="cmtt-8"> </span><span
|
|---|
| 8438 | class="cmtt-8"> </span><span
|
|---|
| 8439 | class="cmtt-8"> </span><span
|
|---|
| 8440 | class="cmtt-8"> </span><span
|
|---|
| 8441 | class="cmsy-8">}</span><br class="fancyvrb" /><a
|
|---|
| 8442 | id="x1-103188r21"></a><span
|
|---|
| 8443 | class="cmr-6">21</span><br class="fancyvrb" /><a
|
|---|
| 8444 | id="x1-103190r22"></a><span
|
|---|
| 8445 | class="cmr-6">22</span><span
|
|---|
| 8446 | class="cmtt-8"> 13)</span><span
|
|---|
| 8447 | class="cmtt-8"> if</span><span
|
|---|
| 8448 | class="cmtt-8"> (</span><span
|
|---|
| 8449 | class="cmtt-8"> [hx]</span><span
|
|---|
| 8450 | class="cmtt-8"> is</span><span
|
|---|
| 8451 | class="cmtt-8"> greater</span><span
|
|---|
| 8452 | class="cmtt-8"> than</span><span
|
|---|
| 8453 | class="cmtt-8"> [n]</span><span
|
|---|
| 8454 | class="cmtt-8"> )</span><span
|
|---|
| 8455 | class="cmtt-8"> </span><span
|
|---|
| 8456 | class="cmsy-8">{</span><br class="fancyvrb" /><a
|
|---|
| 8457 | id="x1-103192r23"></a><span
|
|---|
| 8458 | class="cmr-6">23</span>
|
|---|
| 8459 | <br class="fancyvrb" /><a
|
|---|
| 8460 | id="x1-103194r24"></a><span
|
|---|
| 8461 | class="cmr-6">24</span><span
|
|---|
| 8462 | class="cmtt-8"> </span><span
|
|---|
| 8463 | class="cmtt-8"> </span><span
|
|---|
| 8464 | class="cmtt-8"> </span><span
|
|---|
| 8465 | class="cmtt-8"> </span><span
|
|---|
| 8466 | class="cmtt-8"> </span><span
|
|---|
| 8467 | class="cmtt-8"> </span><span
|
|---|
| 8468 | class="cmtt-8"> </span><span
|
|---|
| 8469 | class="cmtt-8"> </span><span
|
|---|
| 8470 | class="cmtt-8"> </span><span
|
|---|
| 8471 | class="cmtt-8"> </span><span
|
|---|
| 8472 | class="cmtt-8"> </span><span
|
|---|
| 8473 | class="cmtt-8"> 14)</span><span
|
|---|
| 8474 | class="cmtt-8"> truncate</span><span
|
|---|
| 8475 | class="cmtt-8"> vector</span><span
|
|---|
| 8476 | class="cmtt-8"> [floor]</span><span
|
|---|
| 8477 | class="cmtt-8"> to</span><span
|
|---|
| 8478 | class="cmtt-8"> [n]</span><span
|
|---|
| 8479 | class="cmtt-8"> elements</span><br class="fancyvrb" /><a
|
|---|
| 8480 | id="x1-103196r25"></a><span
|
|---|
| 8481 | class="cmr-6">25</span><br class="fancyvrb" /><a
|
|---|
| 8482 | id="x1-103198r26"></a><span
|
|---|
| 8483 | class="cmr-6">26</span><span
|
|---|
| 8484 | class="cmtt-8"> </span><span
|
|---|
| 8485 | class="cmtt-8"> </span><span
|
|---|
| 8486 | class="cmtt-8"> </span><span
|
|---|
| 8487 | class="cmtt-8"> </span><span
|
|---|
| 8488 | class="cmtt-8"> </span><span
|
|---|
| 8489 | class="cmsy-8">}</span><br class="fancyvrb" /><a
|
|---|
| 8490 | id="x1-103200r27"></a><span
|
|---|
| 8491 | class="cmr-6">27</span><br class="fancyvrb" /><a
|
|---|
| 8492 | id="x1-103202r28"></a><span
|
|---|
| 8493 | class="cmr-6">28</span><span
|
|---|
| 8494 | class="cmtt-8"> 15)</span><span
|
|---|
| 8495 | class="cmtt-8"> for</span><span
|
|---|
| 8496 | class="cmtt-8"> each</span><span
|
|---|
| 8497 | class="cmtt-8"> scalar</span><span
|
|---|
| 8498 | class="cmtt-8"> in</span><span
|
|---|
| 8499 | class="cmtt-8"> vector</span><span
|
|---|
| 8500 | class="cmtt-8"> [floor],</span><span
|
|---|
| 8501 | class="cmtt-8"> perform</span><span
|
|---|
| 8502 | class="cmtt-8"> a</span><span
|
|---|
| 8503 | class="cmtt-8"> lookup</span><span
|
|---|
| 8504 | class="cmtt-8"> substitution</span><span
|
|---|
| 8505 | class="cmtt-8"> using</span>
|
|---|
| 8506 | <br class="fancyvrb" /><a
|
|---|
| 8507 | id="x1-103204r29"></a><span
|
|---|
| 8508 | class="cmr-6">29</span><span
|
|---|
| 8509 | class="cmtt-8"> </span><span
|
|---|
| 8510 | class="cmtt-8"> </span><span
|
|---|
| 8511 | class="cmtt-8"> </span><span
|
|---|
| 8512 | class="cmtt-8"> </span><span
|
|---|
| 8513 | class="cmtt-8"> the</span><span
|
|---|
| 8514 | class="cmtt-8"> scalar</span><span
|
|---|
| 8515 | class="cmtt-8"> value</span><span
|
|---|
| 8516 | class="cmtt-8"> from</span><span
|
|---|
| 8517 | class="cmtt-8"> [floor]</span><span
|
|---|
| 8518 | class="cmtt-8"> as</span><span
|
|---|
| 8519 | class="cmtt-8"> an</span><span
|
|---|
| 8520 | class="cmtt-8"> offset</span><span
|
|---|
| 8521 | class="cmtt-8"> into</span><span
|
|---|
| 8522 | class="cmtt-8"> the</span><span
|
|---|
| 8523 | class="cmtt-8"> vector</span><span
|
|---|
| 8524 | class="cmtt-8"> </span><a
|
|---|
| 8525 | href="#x1-12700010.1"><span
|
|---|
| 8526 | class="cmtt-8">[floor1</span><span
|
|---|
| 8527 | class="cmtt-8">_inverse</span><span
|
|---|
| 8528 | class="cmtt-8">_dB</span><span
|
|---|
| 8529 | class="cmtt-8">_static</span><span
|
|---|
| 8530 | class="cmtt-8">_table]</span></a><br class="fancyvrb" /><a
|
|---|
| 8531 | id="x1-103206r30"></a><span
|
|---|
| 8532 | class="cmr-6">30</span><br class="fancyvrb" /><a
|
|---|
| 8533 | id="x1-103208r31"></a><span
|
|---|
| 8534 | class="cmr-6">31</span><span
|
|---|
| 8535 | class="cmtt-8"> 16)</span><span
|
|---|
| 8536 | class="cmtt-8"> done</span><br class="fancyvrb" /><a
|
|---|
| 8537 | id="x1-103210r32"></a><span
|
|---|
| 8538 | class="cmr-6">32</span></div>
|
|---|
| 8539 | </dd></dl>
|
|---|
| 8540 |
|
|---|
| 8541 |
|
|---|
| 8542 |
|
|---|
| 8543 | <h3 class="sectionHead"><span class="titlemark">8. </span> <a
|
|---|
| 8544 | id="x1-1040008"></a>Residue setup and decode</h3>
|
|---|
| 8545 | <!--l. 5--><p class="noindent" >
|
|---|
| 8546 | <h4 class="subsectionHead"><span class="titlemark">8.1. </span> <a
|
|---|
| 8547 | id="x1-1050008.1"></a>Overview</h4>
|
|---|
| 8548 | <!--l. 7--><p class="noindent" >A residue vector represents the fine detail of the audio spectrum of one channel in an audio frame
|
|---|
| 8549 | after the encoder subtracts the floor curve and performs any channel coupling. A residue vector
|
|---|
| 8550 | may represent spectral lines, spectral magnitude, spectral phase or hybrids as mixed by channel
|
|---|
| 8551 | coupling. The exact semantic content of the vector does not matter to the residue
|
|---|
| 8552 | abstraction.
|
|---|
| 8553 | <!--l. 14--><p class="noindent" >Whatever the exact qualities, the Vorbis residue abstraction codes the residue vectors into the
|
|---|
| 8554 | bitstream packet, and then reconstructs the vectors during decode. Vorbis makes use of three
|
|---|
| 8555 | different encoding variants (numbered 0, 1 and 2) of the same basic vector encoding
|
|---|
| 8556 | abstraction.
|
|---|
| 8557 | <!--l. 22--><p class="noindent" >
|
|---|
| 8558 | <h4 class="subsectionHead"><span class="titlemark">8.2. </span> <a
|
|---|
| 8559 | id="x1-1060008.2"></a>Residue format</h4>
|
|---|
| 8560 | <!--l. 24--><p class="noindent" >Residue format partitions each vector in the vector bundle into chunks, classifies each
|
|---|
| 8561 | chunk, encodes the chunk classifications and finally encodes the chunks themselves
|
|---|
| 8562 | using the the specific VQ arrangement defined for each selected classification. The
|
|---|
| 8563 | exact interleaving and partitioning vary by residue encoding number, however the
|
|---|
| 8564 | high-level process used to classify and encode the residue vector is the same in all three
|
|---|
| 8565 | variants.
|
|---|
| 8566 | <!--l. 32--><p class="noindent" >A set of coded residue vectors are all of the same length. High level coding structure, ignoring for
|
|---|
| 8567 | the moment exactly how a partition is encoded and simply trusting that it is, is as
|
|---|
| 8568 | follows:
|
|---|
| 8569 | <ul class="itemize1">
|
|---|
| 8570 | <li class="itemize">Each vector is partitioned into multiple equal sized chunks according to configuration
|
|---|
| 8571 | specified. If we have a vector size of <span
|
|---|
| 8572 | class="cmti-12">n</span>, a partition size <span
|
|---|
| 8573 | class="cmti-12">residue</span><span
|
|---|
| 8574 | class="cmti-12">_partition</span><span
|
|---|
| 8575 | class="cmti-12">_size</span>,
|
|---|
| 8576 | and a total of <span
|
|---|
| 8577 | class="cmti-12">ch </span>residue vectors, the total number of partitioned chunks coded
|
|---|
| 8578 |
|
|---|
| 8579 |
|
|---|
| 8580 |
|
|---|
| 8581 | is <span
|
|---|
| 8582 | class="cmti-12">n</span>/<span
|
|---|
| 8583 | class="cmti-12">residue</span><span
|
|---|
| 8584 | class="cmti-12">_partition</span><span
|
|---|
| 8585 | class="cmti-12">_size</span>*<span
|
|---|
| 8586 | class="cmti-12">ch</span>. It is important to note that the integer division
|
|---|
| 8587 | truncates. In the below example, we assume an example <span
|
|---|
| 8588 | class="cmti-12">residue</span><span
|
|---|
| 8589 | class="cmti-12">_partition</span><span
|
|---|
| 8590 | class="cmti-12">_size </span>of 8.
|
|---|
| 8591 | </li>
|
|---|
| 8592 | <li class="itemize">Each partition in each vector has a classification number that specifies which of
|
|---|
| 8593 | multiple configured VQ codebook setups are used to decode that partition. The
|
|---|
| 8594 | classification numbers of each partition can be thought of as forming a vector in
|
|---|
| 8595 | their own right, as in the illustration below. Just as the residue vectors are coded
|
|---|
| 8596 | in grouped partitions to increase encoding efficiency, the classification vector is also
|
|---|
| 8597 | partitioned into chunks. The integer elements of each scalar in a classification chunk
|
|---|
| 8598 | are built into a single scalar that represents the classification numbers in that chunk.
|
|---|
| 8599 | In the below example, the classification codeword encodes two classification numbers.
|
|---|
| 8600 | </li>
|
|---|
| 8601 | <li class="itemize">The values in a residue vector may be encoded monolithically in a single pass through
|
|---|
| 8602 | the residue vector, but more often efficient codebook design dictates that each vector
|
|---|
| 8603 | is encoded as the additive sum of several passes through the residue vector using
|
|---|
| 8604 | more than one VQ codebook. Thus, each residue value potentially accumulates values
|
|---|
| 8605 | from multiple decode passes. The classification value associated with a partition is
|
|---|
| 8606 | the same in each pass, thus the classification codeword is coded only in the first pass.
|
|---|
| 8607 | </li></ul>
|
|---|
| 8608 | <div class="center"
|
|---|
| 8609 | >
|
|---|
| 8610 | <!--l. 69--><p class="noindent" >
|
|---|
| 8611 |
|
|---|
| 8612 | <!--l. 70--><p class="noindent" ><img
|
|---|
| 8613 | src="residue-pack.png" alt="PIC"
|
|---|
| 8614 | >
|
|---|
| 8615 | <br /> <div class="caption"
|
|---|
| 8616 | ><span class="id">Figure 11: </span><span
|
|---|
| 8617 | class="content">illustration of residue vector format</span></div><!--tex4ht:label?: x1-10600111 -->
|
|---|
| 8618 | </div>
|
|---|
| 8619 | <!--l. 76--><p class="noindent" >
|
|---|
| 8620 | <h4 class="subsectionHead"><span class="titlemark">8.3. </span> <a
|
|---|
| 8621 | id="x1-1070008.3"></a>residue 0</h4>
|
|---|
| 8622 | <!--l. 78--><p class="noindent" >Residue 0 and 1 differ only in the way the values within a residue partition are interleaved during
|
|---|
| 8623 | partition encoding (visually treated as a black box–or cyan box or brown box–in the above
|
|---|
| 8624 | figure).
|
|---|
| 8625 | <!--l. 82--><p class="noindent" >Residue encoding 0 interleaves VQ encoding according to the dimension of the codebook used to
|
|---|
| 8626 |
|
|---|
| 8627 |
|
|---|
| 8628 |
|
|---|
| 8629 | encode a partition in a specific pass. The dimension of the codebook need not be the same in
|
|---|
| 8630 | multiple passes, however the partition size must be an even multiple of the codebook
|
|---|
| 8631 | dimension.
|
|---|
| 8632 | <!--l. 88--><p class="noindent" >As an example, assume a partition vector of size eight, to be encoded by residue 0 using
|
|---|
| 8633 | codebook sizes of 8, 4, 2 and 1:
|
|---|
| 8634 | <!--l. 91--><p class="noindent" >
|
|---|
| 8635 | <div class="fancyvrb" id="fancyvrb33"><a
|
|---|
| 8636 | id="x1-107002r1"></a><span
|
|---|
| 8637 | class="cmr-6">1</span><br class="fancyvrb" /><a
|
|---|
| 8638 | id="x1-107004r2"></a><span
|
|---|
| 8639 | class="cmr-6">2</span><span
|
|---|
| 8640 | class="cmtt-8"> </span><span
|
|---|
| 8641 | class="cmtt-8"> </span><span
|
|---|
| 8642 | class="cmtt-8"> </span><span
|
|---|
| 8643 | class="cmtt-8"> </span><span
|
|---|
| 8644 | class="cmtt-8"> </span><span
|
|---|
| 8645 | class="cmtt-8"> </span><span
|
|---|
| 8646 | class="cmtt-8"> </span><span
|
|---|
| 8647 | class="cmtt-8"> </span><span
|
|---|
| 8648 | class="cmtt-8"> </span><span
|
|---|
| 8649 | class="cmtt-8"> </span><span
|
|---|
| 8650 | class="cmtt-8"> </span><span
|
|---|
| 8651 | class="cmtt-8"> original</span><span
|
|---|
| 8652 | class="cmtt-8"> residue</span><span
|
|---|
| 8653 | class="cmtt-8"> vector:</span><span
|
|---|
| 8654 | class="cmtt-8"> [</span><span
|
|---|
| 8655 | class="cmtt-8"> 0</span><span
|
|---|
| 8656 | class="cmtt-8"> 1</span><span
|
|---|
| 8657 | class="cmtt-8"> 2</span><span
|
|---|
| 8658 | class="cmtt-8"> 3</span><span
|
|---|
| 8659 | class="cmtt-8"> 4</span><span
|
|---|
| 8660 | class="cmtt-8"> 5</span><span
|
|---|
| 8661 | class="cmtt-8"> 6</span><span
|
|---|
| 8662 | class="cmtt-8"> 7</span><span
|
|---|
| 8663 | class="cmtt-8"> ]</span><br class="fancyvrb" /><a
|
|---|
| 8664 | id="x1-107006r3"></a><span
|
|---|
| 8665 | class="cmr-6">3</span><br class="fancyvrb" /><a
|
|---|
| 8666 | id="x1-107008r4"></a><span
|
|---|
| 8667 | class="cmr-6">4</span><span
|
|---|
| 8668 | class="cmtt-8">codebook</span><span
|
|---|
| 8669 | class="cmtt-8"> dimensions</span><span
|
|---|
| 8670 | class="cmtt-8"> =</span><span
|
|---|
| 8671 | class="cmtt-8"> 8</span><span
|
|---|
| 8672 | class="cmtt-8"> </span><span
|
|---|
| 8673 | class="cmtt-8"> encoded</span><span
|
|---|
| 8674 | class="cmtt-8"> as:</span><span
|
|---|
| 8675 | class="cmtt-8"> [</span><span
|
|---|
| 8676 | class="cmtt-8"> 0</span><span
|
|---|
| 8677 | class="cmtt-8"> 1</span><span
|
|---|
| 8678 | class="cmtt-8"> 2</span><span
|
|---|
| 8679 | class="cmtt-8"> 3</span><span
|
|---|
| 8680 | class="cmtt-8"> 4</span><span
|
|---|
| 8681 | class="cmtt-8"> 5</span><span
|
|---|
| 8682 | class="cmtt-8"> 6</span><span
|
|---|
| 8683 | class="cmtt-8"> 7</span><span
|
|---|
| 8684 | class="cmtt-8"> ]</span><br class="fancyvrb" /><a
|
|---|
| 8685 | id="x1-107010r5"></a><span
|
|---|
| 8686 | class="cmr-6">5</span>
|
|---|
| 8687 | <br class="fancyvrb" /><a
|
|---|
| 8688 | id="x1-107012r6"></a><span
|
|---|
| 8689 | class="cmr-6">6</span><span
|
|---|
| 8690 | class="cmtt-8">codebook</span><span
|
|---|
| 8691 | class="cmtt-8"> dimensions</span><span
|
|---|
| 8692 | class="cmtt-8"> =</span><span
|
|---|
| 8693 | class="cmtt-8"> 4</span><span
|
|---|
| 8694 | class="cmtt-8"> </span><span
|
|---|
| 8695 | class="cmtt-8"> encoded</span><span
|
|---|
| 8696 | class="cmtt-8"> as:</span><span
|
|---|
| 8697 | class="cmtt-8"> [</span><span
|
|---|
| 8698 | class="cmtt-8"> 0</span><span
|
|---|
| 8699 | class="cmtt-8"> 2</span><span
|
|---|
| 8700 | class="cmtt-8"> 4</span><span
|
|---|
| 8701 | class="cmtt-8"> 6</span><span
|
|---|
| 8702 | class="cmtt-8"> ],</span><span
|
|---|
| 8703 | class="cmtt-8"> [</span><span
|
|---|
| 8704 | class="cmtt-8"> 1</span><span
|
|---|
| 8705 | class="cmtt-8"> 3</span><span
|
|---|
| 8706 | class="cmtt-8"> 5</span><span
|
|---|
| 8707 | class="cmtt-8"> 7</span><span
|
|---|
| 8708 | class="cmtt-8"> ]</span><br class="fancyvrb" /><a
|
|---|
| 8709 | id="x1-107014r7"></a><span
|
|---|
| 8710 | class="cmr-6">7</span><br class="fancyvrb" /><a
|
|---|
| 8711 | id="x1-107016r8"></a><span
|
|---|
| 8712 | class="cmr-6">8</span><span
|
|---|
| 8713 | class="cmtt-8">codebook</span><span
|
|---|
| 8714 | class="cmtt-8"> dimensions</span><span
|
|---|
| 8715 | class="cmtt-8"> =</span><span
|
|---|
| 8716 | class="cmtt-8"> 2</span><span
|
|---|
| 8717 | class="cmtt-8"> </span><span
|
|---|
| 8718 | class="cmtt-8"> encoded</span><span
|
|---|
| 8719 | class="cmtt-8"> as:</span><span
|
|---|
| 8720 | class="cmtt-8"> [</span><span
|
|---|
| 8721 | class="cmtt-8"> 0</span><span
|
|---|
| 8722 | class="cmtt-8"> 4</span><span
|
|---|
| 8723 | class="cmtt-8"> ],</span><span
|
|---|
| 8724 | class="cmtt-8"> [</span><span
|
|---|
| 8725 | class="cmtt-8"> 1</span><span
|
|---|
| 8726 | class="cmtt-8"> 5</span><span
|
|---|
| 8727 | class="cmtt-8"> ],</span><span
|
|---|
| 8728 | class="cmtt-8"> [</span><span
|
|---|
| 8729 | class="cmtt-8"> 2</span><span
|
|---|
| 8730 | class="cmtt-8"> 6</span><span
|
|---|
| 8731 | class="cmtt-8"> ],</span><span
|
|---|
| 8732 | class="cmtt-8"> [</span><span
|
|---|
| 8733 | class="cmtt-8"> 3</span><span
|
|---|
| 8734 | class="cmtt-8"> 7</span><span
|
|---|
| 8735 | class="cmtt-8"> ]</span><br class="fancyvrb" /><a
|
|---|
| 8736 | id="x1-107018r9"></a><span
|
|---|
| 8737 | class="cmr-6">9</span>
|
|---|
| 8738 | <br class="fancyvrb" /><a
|
|---|
| 8739 | id="x1-107020r10"></a><span
|
|---|
| 8740 | class="cmr-6">10</span><span
|
|---|
| 8741 | class="cmtt-8">codebook</span><span
|
|---|
| 8742 | class="cmtt-8"> dimensions</span><span
|
|---|
| 8743 | class="cmtt-8"> =</span><span
|
|---|
| 8744 | class="cmtt-8"> 1</span><span
|
|---|
| 8745 | class="cmtt-8"> </span><span
|
|---|
| 8746 | class="cmtt-8"> encoded</span><span
|
|---|
| 8747 | class="cmtt-8"> as:</span><span
|
|---|
| 8748 | class="cmtt-8"> [</span><span
|
|---|
| 8749 | class="cmtt-8"> 0</span><span
|
|---|
| 8750 | class="cmtt-8"> ],</span><span
|
|---|
| 8751 | class="cmtt-8"> [</span><span
|
|---|
| 8752 | class="cmtt-8"> 1</span><span
|
|---|
| 8753 | class="cmtt-8"> ],</span><span
|
|---|
| 8754 | class="cmtt-8"> [</span><span
|
|---|
| 8755 | class="cmtt-8"> 2</span><span
|
|---|
| 8756 | class="cmtt-8"> ],</span><span
|
|---|
| 8757 | class="cmtt-8"> [</span><span
|
|---|
| 8758 | class="cmtt-8"> 3</span><span
|
|---|
| 8759 | class="cmtt-8"> ],</span><span
|
|---|
| 8760 | class="cmtt-8"> [</span><span
|
|---|
| 8761 | class="cmtt-8"> 4</span><span
|
|---|
| 8762 | class="cmtt-8"> ],</span><span
|
|---|
| 8763 | class="cmtt-8"> [</span><span
|
|---|
| 8764 | class="cmtt-8"> 5</span><span
|
|---|
| 8765 | class="cmtt-8"> ],</span><span
|
|---|
| 8766 | class="cmtt-8"> [</span><span
|
|---|
| 8767 | class="cmtt-8"> 6</span><span
|
|---|
| 8768 | class="cmtt-8"> ],</span><span
|
|---|
| 8769 | class="cmtt-8"> [</span><span
|
|---|
| 8770 | class="cmtt-8"> 7</span><span
|
|---|
| 8771 | class="cmtt-8"> ]</span><br class="fancyvrb" /><a
|
|---|
| 8772 | id="x1-107022r11"></a><span
|
|---|
| 8773 | class="cmr-6">11</span></div>
|
|---|
| 8774 | <!--l. 105--><p class="noindent" >It is worth mentioning at this point that no configurable value in the residue coding setup is
|
|---|
| 8775 | restricted to a power of two.
|
|---|
| 8776 | <!--l. 110--><p class="noindent" >
|
|---|
| 8777 | <h4 class="subsectionHead"><span class="titlemark">8.4. </span> <a
|
|---|
| 8778 | id="x1-1080008.4"></a>residue 1</h4>
|
|---|
| 8779 | <!--l. 112--><p class="noindent" >Residue 1 does not interleave VQ encoding. It represents partition vector scalars in order. As
|
|---|
| 8780 | with residue 0, however, partition length must be an integer multiple of the codebook dimension,
|
|---|
| 8781 | although dimension may vary from pass to pass.
|
|---|
| 8782 | <!--l. 117--><p class="noindent" >As an example, assume a partition vector of size eight, to be encoded by residue 0 using
|
|---|
| 8783 | codebook sizes of 8, 4, 2 and 1:
|
|---|
| 8784 | <!--l. 120--><p class="noindent" >
|
|---|
| 8785 | <div class="fancyvrb" id="fancyvrb34"><a
|
|---|
| 8786 | id="x1-108002r1"></a><span
|
|---|
| 8787 | class="cmr-6">1</span><br class="fancyvrb" /><a
|
|---|
| 8788 | id="x1-108004r2"></a><span
|
|---|
| 8789 | class="cmr-6">2</span><span
|
|---|
| 8790 | class="cmtt-8"> </span><span
|
|---|
| 8791 | class="cmtt-8"> </span><span
|
|---|
| 8792 | class="cmtt-8"> </span><span
|
|---|
| 8793 | class="cmtt-8"> </span><span
|
|---|
| 8794 | class="cmtt-8"> </span><span
|
|---|
| 8795 | class="cmtt-8"> </span><span
|
|---|
| 8796 | class="cmtt-8"> </span><span
|
|---|
| 8797 | class="cmtt-8"> </span><span
|
|---|
| 8798 | class="cmtt-8"> </span><span
|
|---|
| 8799 | class="cmtt-8"> </span><span
|
|---|
| 8800 | class="cmtt-8"> </span><span
|
|---|
| 8801 | class="cmtt-8"> original</span><span
|
|---|
| 8802 | class="cmtt-8"> residue</span><span
|
|---|
| 8803 | class="cmtt-8"> vector:</span><span
|
|---|
| 8804 | class="cmtt-8"> [</span><span
|
|---|
| 8805 | class="cmtt-8"> 0</span><span
|
|---|
| 8806 | class="cmtt-8"> 1</span><span
|
|---|
| 8807 | class="cmtt-8"> 2</span><span
|
|---|
| 8808 | class="cmtt-8"> 3</span><span
|
|---|
| 8809 | class="cmtt-8"> 4</span><span
|
|---|
| 8810 | class="cmtt-8"> 5</span><span
|
|---|
| 8811 | class="cmtt-8"> 6</span><span
|
|---|
| 8812 | class="cmtt-8"> 7</span><span
|
|---|
| 8813 | class="cmtt-8"> ]</span><br class="fancyvrb" /><a
|
|---|
| 8814 | id="x1-108006r3"></a><span
|
|---|
| 8815 | class="cmr-6">3</span><br class="fancyvrb" /><a
|
|---|
| 8816 | id="x1-108008r4"></a><span
|
|---|
| 8817 | class="cmr-6">4</span><span
|
|---|
| 8818 | class="cmtt-8">codebook</span><span
|
|---|
| 8819 | class="cmtt-8"> dimensions</span><span
|
|---|
| 8820 | class="cmtt-8"> =</span><span
|
|---|
| 8821 | class="cmtt-8"> 8</span><span
|
|---|
| 8822 | class="cmtt-8"> </span><span
|
|---|
| 8823 | class="cmtt-8"> encoded</span><span
|
|---|
| 8824 | class="cmtt-8"> as:</span><span
|
|---|
| 8825 | class="cmtt-8"> [</span><span
|
|---|
| 8826 | class="cmtt-8"> 0</span><span
|
|---|
| 8827 | class="cmtt-8"> 1</span><span
|
|---|
| 8828 | class="cmtt-8"> 2</span><span
|
|---|
| 8829 | class="cmtt-8"> 3</span><span
|
|---|
| 8830 | class="cmtt-8"> 4</span><span
|
|---|
| 8831 | class="cmtt-8"> 5</span><span
|
|---|
| 8832 | class="cmtt-8"> 6</span><span
|
|---|
| 8833 | class="cmtt-8"> 7</span><span
|
|---|
| 8834 | class="cmtt-8"> ]</span><br class="fancyvrb" /><a
|
|---|
| 8835 | id="x1-108010r5"></a><span
|
|---|
| 8836 | class="cmr-6">5</span>
|
|---|
| 8837 | <br class="fancyvrb" /><a
|
|---|
| 8838 | id="x1-108012r6"></a><span
|
|---|
| 8839 | class="cmr-6">6</span><span
|
|---|
| 8840 | class="cmtt-8">codebook</span><span
|
|---|
| 8841 | class="cmtt-8"> dimensions</span><span
|
|---|
| 8842 | class="cmtt-8"> =</span><span
|
|---|
| 8843 | class="cmtt-8"> 4</span><span
|
|---|
| 8844 | class="cmtt-8"> </span><span
|
|---|
| 8845 | class="cmtt-8"> encoded</span><span
|
|---|
| 8846 | class="cmtt-8"> as:</span><span
|
|---|
| 8847 | class="cmtt-8"> [</span><span
|
|---|
| 8848 | class="cmtt-8"> 0</span><span
|
|---|
| 8849 | class="cmtt-8"> 1</span><span
|
|---|
| 8850 | class="cmtt-8"> 2</span><span
|
|---|
| 8851 | class="cmtt-8"> 3</span><span
|
|---|
| 8852 | class="cmtt-8"> ],</span><span
|
|---|
| 8853 | class="cmtt-8"> [</span><span
|
|---|
| 8854 | class="cmtt-8"> 4</span><span
|
|---|
| 8855 | class="cmtt-8"> 5</span><span
|
|---|
| 8856 | class="cmtt-8"> 6</span><span
|
|---|
| 8857 | class="cmtt-8"> 7</span><span
|
|---|
| 8858 | class="cmtt-8"> ]</span><br class="fancyvrb" /><a
|
|---|
| 8859 | id="x1-108014r7"></a><span
|
|---|
| 8860 | class="cmr-6">7</span><br class="fancyvrb" /><a
|
|---|
| 8861 | id="x1-108016r8"></a><span
|
|---|
| 8862 | class="cmr-6">8</span><span
|
|---|
| 8863 | class="cmtt-8">codebook</span><span
|
|---|
| 8864 | class="cmtt-8"> dimensions</span><span
|
|---|
| 8865 | class="cmtt-8"> =</span><span
|
|---|
| 8866 | class="cmtt-8"> 2</span><span
|
|---|
| 8867 | class="cmtt-8"> </span><span
|
|---|
| 8868 | class="cmtt-8"> encoded</span><span
|
|---|
| 8869 | class="cmtt-8"> as:</span><span
|
|---|
| 8870 | class="cmtt-8"> [</span><span
|
|---|
| 8871 | class="cmtt-8"> 0</span><span
|
|---|
| 8872 | class="cmtt-8"> 1</span><span
|
|---|
| 8873 | class="cmtt-8"> ],</span><span
|
|---|
| 8874 | class="cmtt-8"> [</span><span
|
|---|
| 8875 | class="cmtt-8"> 2</span><span
|
|---|
| 8876 | class="cmtt-8"> 3</span><span
|
|---|
| 8877 | class="cmtt-8"> ],</span><span
|
|---|
| 8878 | class="cmtt-8"> [</span><span
|
|---|
| 8879 | class="cmtt-8"> 4</span><span
|
|---|
| 8880 | class="cmtt-8"> 5</span><span
|
|---|
| 8881 | class="cmtt-8"> ],</span><span
|
|---|
| 8882 | class="cmtt-8"> [</span><span
|
|---|
| 8883 | class="cmtt-8"> 6</span><span
|
|---|
| 8884 | class="cmtt-8"> 7</span><span
|
|---|
| 8885 | class="cmtt-8"> ]</span><br class="fancyvrb" /><a
|
|---|
| 8886 | id="x1-108018r9"></a><span
|
|---|
| 8887 | class="cmr-6">9</span>
|
|---|
| 8888 | <br class="fancyvrb" /><a
|
|---|
| 8889 | id="x1-108020r10"></a><span
|
|---|
| 8890 | class="cmr-6">10</span><span
|
|---|
| 8891 | class="cmtt-8">codebook</span><span
|
|---|
| 8892 | class="cmtt-8"> dimensions</span><span
|
|---|
| 8893 | class="cmtt-8"> =</span><span
|
|---|
| 8894 | class="cmtt-8"> 1</span><span
|
|---|
| 8895 | class="cmtt-8"> </span><span
|
|---|
| 8896 | class="cmtt-8"> encoded</span><span
|
|---|
| 8897 | class="cmtt-8"> as:</span><span
|
|---|
| 8898 | class="cmtt-8"> [</span><span
|
|---|
| 8899 | class="cmtt-8"> 0</span><span
|
|---|
| 8900 | class="cmtt-8"> ],</span><span
|
|---|
| 8901 | class="cmtt-8"> [</span><span
|
|---|
| 8902 | class="cmtt-8"> 1</span><span
|
|---|
| 8903 | class="cmtt-8"> ],</span><span
|
|---|
| 8904 | class="cmtt-8"> [</span><span
|
|---|
| 8905 | class="cmtt-8"> 2</span><span
|
|---|
| 8906 | class="cmtt-8"> ],</span><span
|
|---|
| 8907 | class="cmtt-8"> [</span><span
|
|---|
| 8908 | class="cmtt-8"> 3</span><span
|
|---|
| 8909 | class="cmtt-8"> ],</span><span
|
|---|
| 8910 | class="cmtt-8"> [</span><span
|
|---|
| 8911 | class="cmtt-8"> 4</span><span
|
|---|
| 8912 | class="cmtt-8"> ],</span><span
|
|---|
| 8913 | class="cmtt-8"> [</span><span
|
|---|
| 8914 | class="cmtt-8"> 5</span><span
|
|---|
| 8915 | class="cmtt-8"> ],</span><span
|
|---|
| 8916 | class="cmtt-8"> [</span><span
|
|---|
| 8917 | class="cmtt-8"> 6</span><span
|
|---|
| 8918 | class="cmtt-8"> ],</span><span
|
|---|
| 8919 | class="cmtt-8"> [</span><span
|
|---|
| 8920 | class="cmtt-8"> 7</span><span
|
|---|
| 8921 | class="cmtt-8"> ]</span><br class="fancyvrb" /><a
|
|---|
| 8922 | id="x1-108022r11"></a><span
|
|---|
| 8923 | class="cmr-6">11</span></div>
|
|---|
| 8924 | <!--l. 136--><p class="noindent" >
|
|---|
| 8925 | <h4 class="subsectionHead"><span class="titlemark">8.5. </span> <a
|
|---|
| 8926 | id="x1-1090008.5"></a>residue 2</h4>
|
|---|
| 8927 | <!--l. 138--><p class="noindent" >Residue type two can be thought of as a variant of residue type 1. Rather than encoding multiple
|
|---|
| 8928 | passed-in vectors as in residue type 1, the <span
|
|---|
| 8929 | class="cmti-12">ch </span>passed in vectors of length <span
|
|---|
| 8930 | class="cmti-12">n </span>are first interleaved
|
|---|
| 8931 | and flattened into a single vector of length <span
|
|---|
| 8932 | class="cmti-12">ch</span>*<span
|
|---|
| 8933 | class="cmti-12">n</span>. Encoding then proceeds as in type 1. Decoding
|
|---|
| 8934 | is as in type 1 with decode interleave reversed. If operating on a single vector to begin with,
|
|---|
| 8935 | residue type 1 and type 2 are equivalent.
|
|---|
| 8936 |
|
|---|
| 8937 |
|
|---|
| 8938 |
|
|---|
| 8939 | <div class="center"
|
|---|
| 8940 | >
|
|---|
| 8941 | <!--l. 146--><p class="noindent" >
|
|---|
| 8942 |
|
|---|
| 8943 | <!--l. 147--><p class="noindent" ><img
|
|---|
| 8944 | src="residue2.png" alt="PIC"
|
|---|
| 8945 | >
|
|---|
| 8946 | <br /> <div class="caption"
|
|---|
| 8947 | ><span class="id">Figure 12: </span><span
|
|---|
| 8948 | class="content">illustration of residue type 2</span></div><!--tex4ht:label?: x1-10900112 -->
|
|---|
| 8949 | </div>
|
|---|
| 8950 | <!--l. 152--><p class="noindent" >
|
|---|
| 8951 | <h4 class="subsectionHead"><span class="titlemark">8.6. </span> <a
|
|---|
| 8952 | id="x1-1100008.6"></a>Residue decode</h4>
|
|---|
| 8953 | <!--l. 154--><p class="noindent" >
|
|---|
| 8954 | <h5 class="subsubsectionHead"><span class="titlemark">8.6.1. </span> <a
|
|---|
| 8955 | id="x1-1110008.6.1"></a>header decode</h5>
|
|---|
| 8956 | <!--l. 156--><p class="noindent" >Header decode for all three residue types is identical.
|
|---|
| 8957 | <div class="fancyvrb" id="fancyvrb35"><a
|
|---|
| 8958 | id="x1-111002r1"></a><span
|
|---|
| 8959 | class="cmr-6">1</span><span
|
|---|
| 8960 | class="cmtt-8"> </span><span
|
|---|
| 8961 | class="cmtt-8"> 1)</span><span
|
|---|
| 8962 | class="cmtt-8"> [residue\_begin]</span><span
|
|---|
| 8963 | class="cmtt-8"> =</span><span
|
|---|
| 8964 | class="cmtt-8"> read</span><span
|
|---|
| 8965 | class="cmtt-8"> 24</span><span
|
|---|
| 8966 | class="cmtt-8"> bits</span><span
|
|---|
| 8967 | class="cmtt-8"> as</span><span
|
|---|
| 8968 | class="cmtt-8"> unsigned</span><span
|
|---|
| 8969 | class="cmtt-8"> integer</span><br class="fancyvrb" /><a
|
|---|
| 8970 | id="x1-111004r2"></a><span
|
|---|
| 8971 | class="cmr-6">2</span><span
|
|---|
| 8972 | class="cmtt-8"> </span><span
|
|---|
| 8973 | class="cmtt-8"> 2)</span><span
|
|---|
| 8974 | class="cmtt-8"> [residue\_end]</span><span
|
|---|
| 8975 | class="cmtt-8"> =</span><span
|
|---|
| 8976 | class="cmtt-8"> read</span><span
|
|---|
| 8977 | class="cmtt-8"> 24</span><span
|
|---|
| 8978 | class="cmtt-8"> bits</span><span
|
|---|
| 8979 | class="cmtt-8"> as</span><span
|
|---|
| 8980 | class="cmtt-8"> unsigned</span><span
|
|---|
| 8981 | class="cmtt-8"> integer</span>
|
|---|
| 8982 | <br class="fancyvrb" /><a
|
|---|
| 8983 | id="x1-111006r3"></a><span
|
|---|
| 8984 | class="cmr-6">3</span><span
|
|---|
| 8985 | class="cmtt-8"> </span><span
|
|---|
| 8986 | class="cmtt-8"> 3)</span><span
|
|---|
| 8987 | class="cmtt-8"> [residue\_partition\_size]</span><span
|
|---|
| 8988 | class="cmtt-8"> =</span><span
|
|---|
| 8989 | class="cmtt-8"> read</span><span
|
|---|
| 8990 | class="cmtt-8"> 24</span><span
|
|---|
| 8991 | class="cmtt-8"> bits</span><span
|
|---|
| 8992 | class="cmtt-8"> as</span><span
|
|---|
| 8993 | class="cmtt-8"> unsigned</span><span
|
|---|
| 8994 | class="cmtt-8"> integer</span><span
|
|---|
| 8995 | class="cmtt-8"> and</span><span
|
|---|
| 8996 | class="cmtt-8"> add</span><span
|
|---|
| 8997 | class="cmtt-8"> one</span>
|
|---|
| 8998 | <br class="fancyvrb" /><a
|
|---|
| 8999 | id="x1-111008r4"></a><span
|
|---|
| 9000 | class="cmr-6">4</span><span
|
|---|
| 9001 | class="cmtt-8"> </span><span
|
|---|
| 9002 | class="cmtt-8"> 4)</span><span
|
|---|
| 9003 | class="cmtt-8"> [residue\_classifications]</span><span
|
|---|
| 9004 | class="cmtt-8"> =</span><span
|
|---|
| 9005 | class="cmtt-8"> read</span><span
|
|---|
| 9006 | class="cmtt-8"> 6</span><span
|
|---|
| 9007 | class="cmtt-8"> bits</span><span
|
|---|
| 9008 | class="cmtt-8"> as</span><span
|
|---|
| 9009 | class="cmtt-8"> unsigned</span><span
|
|---|
| 9010 | class="cmtt-8"> integer</span><span
|
|---|
| 9011 | class="cmtt-8"> and</span><span
|
|---|
| 9012 | class="cmtt-8"> add</span><span
|
|---|
| 9013 | class="cmtt-8"> one</span><br class="fancyvrb" /><a
|
|---|
| 9014 | id="x1-111010r5"></a><span
|
|---|
| 9015 | class="cmr-6">5</span><span
|
|---|
| 9016 | class="cmtt-8"> </span><span
|
|---|
| 9017 | class="cmtt-8"> 5)</span><span
|
|---|
| 9018 | class="cmtt-8"> [residue\_classbook]</span><span
|
|---|
| 9019 | class="cmtt-8"> =</span><span
|
|---|
| 9020 | class="cmtt-8"> read</span><span
|
|---|
| 9021 | class="cmtt-8"> 8</span><span
|
|---|
| 9022 | class="cmtt-8"> bits</span><span
|
|---|
| 9023 | class="cmtt-8"> as</span><span
|
|---|
| 9024 | class="cmtt-8"> unsigned</span><span
|
|---|
| 9025 | class="cmtt-8"> integer</span></div>
|
|---|
| 9026 | <!--l. 165--><p class="noindent" ><span
|
|---|
| 9027 | class="cmtt-12">[residue</span><span
|
|---|
| 9028 | class="cmtt-12">_begin] </span>and <span
|
|---|
| 9029 | class="cmtt-12">[residue</span><span
|
|---|
| 9030 | class="cmtt-12">_end] </span>select the specific sub-portion of each vector that is
|
|---|
| 9031 | actually coded; it implements akin to a bandpass where, for coding purposes, the vector
|
|---|
| 9032 | effectively begins at element <span
|
|---|
| 9033 | class="cmtt-12">[residue</span><span
|
|---|
| 9034 | class="cmtt-12">_begin] </span>and ends at <span
|
|---|
| 9035 | class="cmtt-12">[residue</span><span
|
|---|
| 9036 | class="cmtt-12">_end]</span>. Preceding and
|
|---|
| 9037 | following values in the unpacked vectors are zeroed. Note that for residue type 2, these
|
|---|
| 9038 | values as well as <span
|
|---|
| 9039 | class="cmtt-12">[residue</span><span
|
|---|
| 9040 | class="cmtt-12">_partition</span><span
|
|---|
| 9041 | class="cmtt-12">_size]</span>apply to the interleaved vector, not the
|
|---|
| 9042 | individual vectors before interleave. <span
|
|---|
| 9043 | class="cmtt-12">[residue</span><span
|
|---|
| 9044 | class="cmtt-12">_partition</span><span
|
|---|
| 9045 | class="cmtt-12">_size] </span>is as explained above,
|
|---|
| 9046 | <span
|
|---|
| 9047 | class="cmtt-12">[residue</span><span
|
|---|
| 9048 | class="cmtt-12">_classifications] </span>is the number of possible classification to which a partition can
|
|---|
| 9049 | belong and <span
|
|---|
| 9050 | class="cmtt-12">[residue</span><span
|
|---|
| 9051 | class="cmtt-12">_classbook] </span>is the codebook number used to code classification
|
|---|
| 9052 | codewords. The number of dimensions in book <span
|
|---|
| 9053 | class="cmtt-12">[residue</span><span
|
|---|
| 9054 | class="cmtt-12">_classbook] </span>determines how
|
|---|
| 9055 | many classification values are grouped into a single classification codeword. Note that
|
|---|
| 9056 | the number of entries and dimensions in book <span
|
|---|
| 9057 | class="cmtt-12">[residue</span><span
|
|---|
| 9058 | class="cmtt-12">_classbook]</span>, along with
|
|---|
| 9059 | <span
|
|---|
| 9060 | class="cmtt-12">[residue</span><span
|
|---|
| 9061 | class="cmtt-12">_classifications]</span>, overdetermines to possible number of classification
|
|---|
| 9062 | codewords. If <span
|
|---|
| 9063 | class="cmtt-12">[residue</span><span
|
|---|
| 9064 | class="cmtt-12">_classifications]</span>ˆ<span
|
|---|
| 9065 | class="cmtt-12">[residue</span><span
|
|---|
| 9066 | class="cmtt-12">_classbook]</span>.dimensions exceeds
|
|---|
| 9067 | <span
|
|---|
| 9068 | class="cmtt-12">[residue</span><span
|
|---|
| 9069 | class="cmtt-12">_classbook]</span>.entries, the bitstream should be regarded to be undecodable.
|
|---|
| 9070 |
|
|---|
| 9071 |
|
|---|
| 9072 |
|
|---|
| 9073 | <!--l. 189--><p class="noindent" >Next we read a bitmap pattern that specifies which partition classes code values in which
|
|---|
| 9074 | passes.
|
|---|
| 9075 | <!--l. 192--><p class="noindent" >
|
|---|
| 9076 | <div class="fancyvrb" id="fancyvrb36"><a
|
|---|
| 9077 | id="x1-111012r1"></a><span
|
|---|
| 9078 | class="cmr-6">1</span><span
|
|---|
| 9079 | class="cmtt-8"> </span><span
|
|---|
| 9080 | class="cmtt-8"> 1)</span><span
|
|---|
| 9081 | class="cmtt-8"> iterate</span><span
|
|---|
| 9082 | class="cmtt-8"> [i]</span><span
|
|---|
| 9083 | class="cmtt-8"> over</span><span
|
|---|
| 9084 | class="cmtt-8"> the</span><span
|
|---|
| 9085 | class="cmtt-8"> range</span><span
|
|---|
| 9086 | class="cmtt-8"> 0</span><span
|
|---|
| 9087 | class="cmtt-8"> ...</span><span
|
|---|
| 9088 | class="cmtt-8"> [residue\_classifications]-1</span><span
|
|---|
| 9089 | class="cmtt-8"> {</span><br class="fancyvrb" /><a
|
|---|
| 9090 | id="x1-111014r2"></a><span
|
|---|
| 9091 | class="cmr-6">2</span><br class="fancyvrb" /><a
|
|---|
| 9092 | id="x1-111016r3"></a><span
|
|---|
| 9093 | class="cmr-6">3</span><span
|
|---|
| 9094 | class="cmtt-8"> </span><span
|
|---|
| 9095 | class="cmtt-8"> </span><span
|
|---|
| 9096 | class="cmtt-8"> </span><span
|
|---|
| 9097 | class="cmtt-8"> </span><span
|
|---|
| 9098 | class="cmtt-8"> </span><span
|
|---|
| 9099 | class="cmtt-8"> </span><span
|
|---|
| 9100 | class="cmtt-8"> 2)</span><span
|
|---|
| 9101 | class="cmtt-8"> [high\_bits]</span><span
|
|---|
| 9102 | class="cmtt-8"> =</span><span
|
|---|
| 9103 | class="cmtt-8"> 0</span><br class="fancyvrb" /><a
|
|---|
| 9104 | id="x1-111018r4"></a><span
|
|---|
| 9105 | class="cmr-6">4</span><span
|
|---|
| 9106 | class="cmtt-8"> </span><span
|
|---|
| 9107 | class="cmtt-8"> </span><span
|
|---|
| 9108 | class="cmtt-8"> </span><span
|
|---|
| 9109 | class="cmtt-8"> </span><span
|
|---|
| 9110 | class="cmtt-8"> </span><span
|
|---|
| 9111 | class="cmtt-8"> </span><span
|
|---|
| 9112 | class="cmtt-8"> 3)</span><span
|
|---|
| 9113 | class="cmtt-8"> [low\_bits]</span><span
|
|---|
| 9114 | class="cmtt-8"> =</span><span
|
|---|
| 9115 | class="cmtt-8"> read</span><span
|
|---|
| 9116 | class="cmtt-8"> 3</span><span
|
|---|
| 9117 | class="cmtt-8"> bits</span><span
|
|---|
| 9118 | class="cmtt-8"> as</span><span
|
|---|
| 9119 | class="cmtt-8"> unsigned</span><span
|
|---|
| 9120 | class="cmtt-8"> integer</span>
|
|---|
| 9121 | <br class="fancyvrb" /><a
|
|---|
| 9122 | id="x1-111020r5"></a><span
|
|---|
| 9123 | class="cmr-6">5</span><span
|
|---|
| 9124 | class="cmtt-8"> </span><span
|
|---|
| 9125 | class="cmtt-8"> </span><span
|
|---|
| 9126 | class="cmtt-8"> </span><span
|
|---|
| 9127 | class="cmtt-8"> </span><span
|
|---|
| 9128 | class="cmtt-8"> </span><span
|
|---|
| 9129 | class="cmtt-8"> </span><span
|
|---|
| 9130 | class="cmtt-8"> 4)</span><span
|
|---|
| 9131 | class="cmtt-8"> [bitflag]</span><span
|
|---|
| 9132 | class="cmtt-8"> =</span><span
|
|---|
| 9133 | class="cmtt-8"> read</span><span
|
|---|
| 9134 | class="cmtt-8"> one</span><span
|
|---|
| 9135 | class="cmtt-8"> bit</span><span
|
|---|
| 9136 | class="cmtt-8"> as</span><span
|
|---|
| 9137 | class="cmtt-8"> boolean</span><br class="fancyvrb" /><a
|
|---|
| 9138 | id="x1-111022r6"></a><span
|
|---|
| 9139 | class="cmr-6">6</span><span
|
|---|
| 9140 | class="cmtt-8"> </span><span
|
|---|
| 9141 | class="cmtt-8"> </span><span
|
|---|
| 9142 | class="cmtt-8"> </span><span
|
|---|
| 9143 | class="cmtt-8"> </span><span
|
|---|
| 9144 | class="cmtt-8"> </span><span
|
|---|
| 9145 | class="cmtt-8"> </span><span
|
|---|
| 9146 | class="cmtt-8"> 5)</span><span
|
|---|
| 9147 | class="cmtt-8"> if</span><span
|
|---|
| 9148 | class="cmtt-8"> (</span><span
|
|---|
| 9149 | class="cmtt-8"> [bitflag]</span><span
|
|---|
| 9150 | class="cmtt-8"> is</span><span
|
|---|
| 9151 | class="cmtt-8"> set</span><span
|
|---|
| 9152 | class="cmtt-8"> )</span><span
|
|---|
| 9153 | class="cmtt-8"> then</span><span
|
|---|
| 9154 | class="cmtt-8"> [high\_bits]</span><span
|
|---|
| 9155 | class="cmtt-8"> =</span><span
|
|---|
| 9156 | class="cmtt-8"> read</span><span
|
|---|
| 9157 | class="cmtt-8"> five</span><span
|
|---|
| 9158 | class="cmtt-8"> bits</span><span
|
|---|
| 9159 | class="cmtt-8"> as</span><span
|
|---|
| 9160 | class="cmtt-8"> unsigned</span><span
|
|---|
| 9161 | class="cmtt-8"> integer</span>
|
|---|
| 9162 | <br class="fancyvrb" /><a
|
|---|
| 9163 | id="x1-111024r7"></a><span
|
|---|
| 9164 | class="cmr-6">7</span><span
|
|---|
| 9165 | class="cmtt-8"> </span><span
|
|---|
| 9166 | class="cmtt-8"> </span><span
|
|---|
| 9167 | class="cmtt-8"> </span><span
|
|---|
| 9168 | class="cmtt-8"> </span><span
|
|---|
| 9169 | class="cmtt-8"> </span><span
|
|---|
| 9170 | class="cmtt-8"> </span><span
|
|---|
| 9171 | class="cmtt-8"> 6)</span><span
|
|---|
| 9172 | class="cmtt-8"> vector</span><span
|
|---|
| 9173 | class="cmtt-8"> [residue\_cascade]</span><span
|
|---|
| 9174 | class="cmtt-8"> element</span><span
|
|---|
| 9175 | class="cmtt-8"> [i]</span><span
|
|---|
| 9176 | class="cmtt-8"> =</span><span
|
|---|
| 9177 | class="cmtt-8"> [high\_bits]</span><span
|
|---|
| 9178 | class="cmtt-8"> *</span><span
|
|---|
| 9179 | class="cmtt-8"> 8</span><span
|
|---|
| 9180 | class="cmtt-8"> +</span><span
|
|---|
| 9181 | class="cmtt-8"> [low\_bits]</span><br class="fancyvrb" /><a
|
|---|
| 9182 | id="x1-111026r8"></a><span
|
|---|
| 9183 | class="cmr-6">8</span><span
|
|---|
| 9184 | class="cmtt-8"> </span><span
|
|---|
| 9185 | class="cmtt-8"> </span><span
|
|---|
| 9186 | class="cmtt-8"> </span><span
|
|---|
| 9187 | class="cmtt-8"> </span><span
|
|---|
| 9188 | class="cmtt-8"> }</span><br class="fancyvrb" /><a
|
|---|
| 9189 | id="x1-111028r9"></a><span
|
|---|
| 9190 | class="cmr-6">9</span><span
|
|---|
| 9191 | class="cmtt-8"> </span><span
|
|---|
| 9192 | class="cmtt-8"> 7)</span><span
|
|---|
| 9193 | class="cmtt-8"> done</span></div>
|
|---|
| 9194 | <!--l. 204--><p class="noindent" >Finally, we read in a list of book numbers, each corresponding to specific bit set in the cascade
|
|---|
| 9195 | bitmap. We loop over the possible codebook classifications and the maximum possible number of
|
|---|
| 9196 | encoding stages (8 in Vorbis I, as constrained by the elements of the cascade bitmap being eight
|
|---|
| 9197 | bits):
|
|---|
| 9198 | <!--l. 210--><p class="noindent" >
|
|---|
| 9199 | <div class="fancyvrb" id="fancyvrb37"><a
|
|---|
| 9200 | id="x1-111030r1"></a><span
|
|---|
| 9201 | class="cmr-6">1</span><span
|
|---|
| 9202 | class="cmtt-8"> </span><span
|
|---|
| 9203 | class="cmtt-8"> 1)</span><span
|
|---|
| 9204 | class="cmtt-8"> iterate</span><span
|
|---|
| 9205 | class="cmtt-8"> [i]</span><span
|
|---|
| 9206 | class="cmtt-8"> over</span><span
|
|---|
| 9207 | class="cmtt-8"> the</span><span
|
|---|
| 9208 | class="cmtt-8"> range</span><span
|
|---|
| 9209 | class="cmtt-8"> 0</span><span
|
|---|
| 9210 | class="cmtt-8"> ...</span><span
|
|---|
| 9211 | class="cmtt-8"> [residue\_classifications]-1</span><span
|
|---|
| 9212 | class="cmtt-8"> {</span><br class="fancyvrb" /><a
|
|---|
| 9213 | id="x1-111032r2"></a><span
|
|---|
| 9214 | class="cmr-6">2</span><br class="fancyvrb" /><a
|
|---|
| 9215 | id="x1-111034r3"></a><span
|
|---|
| 9216 | class="cmr-6">3</span><span
|
|---|
| 9217 | class="cmtt-8"> </span><span
|
|---|
| 9218 | class="cmtt-8"> </span><span
|
|---|
| 9219 | class="cmtt-8"> </span><span
|
|---|
| 9220 | class="cmtt-8"> </span><span
|
|---|
| 9221 | class="cmtt-8"> </span><span
|
|---|
| 9222 | class="cmtt-8"> </span><span
|
|---|
| 9223 | class="cmtt-8"> 2)</span><span
|
|---|
| 9224 | class="cmtt-8"> iterate</span><span
|
|---|
| 9225 | class="cmtt-8"> [j]</span><span
|
|---|
| 9226 | class="cmtt-8"> over</span><span
|
|---|
| 9227 | class="cmtt-8"> the</span><span
|
|---|
| 9228 | class="cmtt-8"> range</span><span
|
|---|
| 9229 | class="cmtt-8"> 0</span><span
|
|---|
| 9230 | class="cmtt-8"> ...</span><span
|
|---|
| 9231 | class="cmtt-8"> 7</span><span
|
|---|
| 9232 | class="cmtt-8"> {</span><br class="fancyvrb" /><a
|
|---|
| 9233 | id="x1-111036r4"></a><span
|
|---|
| 9234 | class="cmr-6">4</span>
|
|---|
| 9235 | <br class="fancyvrb" /><a
|
|---|
| 9236 | id="x1-111038r5"></a><span
|
|---|
| 9237 | class="cmr-6">5</span><span
|
|---|
| 9238 | class="cmtt-8"> </span><span
|
|---|
| 9239 | class="cmtt-8"> </span><span
|
|---|
| 9240 | class="cmtt-8"> </span><span
|
|---|
| 9241 | class="cmtt-8"> </span><span
|
|---|
| 9242 | class="cmtt-8"> </span><span
|
|---|
| 9243 | class="cmtt-8"> </span><span
|
|---|
| 9244 | class="cmtt-8"> </span><span
|
|---|
| 9245 | class="cmtt-8"> </span><span
|
|---|
| 9246 | class="cmtt-8"> </span><span
|
|---|
| 9247 | class="cmtt-8"> </span><span
|
|---|
| 9248 | class="cmtt-8"> </span><span
|
|---|
| 9249 | class="cmtt-8"> 3)</span><span
|
|---|
| 9250 | class="cmtt-8"> if</span><span
|
|---|
| 9251 | class="cmtt-8"> (</span><span
|
|---|
| 9252 | class="cmtt-8"> vector</span><span
|
|---|
| 9253 | class="cmtt-8"> [residue\_cascade]</span><span
|
|---|
| 9254 | class="cmtt-8"> element</span><span
|
|---|
| 9255 | class="cmtt-8"> [i]</span><span
|
|---|
| 9256 | class="cmtt-8"> bit</span><span
|
|---|
| 9257 | class="cmtt-8"> [j]</span><span
|
|---|
| 9258 | class="cmtt-8"> is</span><span
|
|---|
| 9259 | class="cmtt-8"> set</span><span
|
|---|
| 9260 | class="cmtt-8"> )</span><span
|
|---|
| 9261 | class="cmtt-8"> {</span><br class="fancyvrb" /><a
|
|---|
| 9262 | id="x1-111040r6"></a><span
|
|---|
| 9263 | class="cmr-6">6</span>
|
|---|
| 9264 | <br class="fancyvrb" /><a
|
|---|
| 9265 | id="x1-111042r7"></a><span
|
|---|
| 9266 | class="cmr-6">7</span><span
|
|---|
| 9267 | class="cmtt-8"> </span><span
|
|---|
| 9268 | class="cmtt-8"> </span><span
|
|---|
| 9269 | class="cmtt-8"> </span><span
|
|---|
| 9270 | class="cmtt-8"> </span><span
|
|---|
| 9271 | class="cmtt-8"> </span><span
|
|---|
| 9272 | class="cmtt-8"> </span><span
|
|---|
| 9273 | class="cmtt-8"> </span><span
|
|---|
| 9274 | class="cmtt-8"> </span><span
|
|---|
| 9275 | class="cmtt-8"> </span><span
|
|---|
| 9276 | class="cmtt-8"> </span><span
|
|---|
| 9277 | class="cmtt-8"> </span><span
|
|---|
| 9278 | class="cmtt-8"> </span><span
|
|---|
| 9279 | class="cmtt-8"> </span><span
|
|---|
| 9280 | class="cmtt-8"> </span><span
|
|---|
| 9281 | class="cmtt-8"> </span><span
|
|---|
| 9282 | class="cmtt-8"> </span><span
|
|---|
| 9283 | class="cmtt-8"> 4)</span><span
|
|---|
| 9284 | class="cmtt-8"> array</span><span
|
|---|
| 9285 | class="cmtt-8"> [residue\_books]</span><span
|
|---|
| 9286 | class="cmtt-8"> element</span><span
|
|---|
| 9287 | class="cmtt-8"> [i][j]</span><span
|
|---|
| 9288 | class="cmtt-8"> =</span><span
|
|---|
| 9289 | class="cmtt-8"> read</span><span
|
|---|
| 9290 | class="cmtt-8"> 8</span><span
|
|---|
| 9291 | class="cmtt-8"> bits</span><span
|
|---|
| 9292 | class="cmtt-8"> as</span><span
|
|---|
| 9293 | class="cmtt-8"> unsigned</span><span
|
|---|
| 9294 | class="cmtt-8"> integer</span><br class="fancyvrb" /><a
|
|---|
| 9295 | id="x1-111044r8"></a><span
|
|---|
| 9296 | class="cmr-6">8</span><br class="fancyvrb" /><a
|
|---|
| 9297 | id="x1-111046r9"></a><span
|
|---|
| 9298 | class="cmr-6">9</span><span
|
|---|
| 9299 | class="cmtt-8"> </span><span
|
|---|
| 9300 | class="cmtt-8"> </span><span
|
|---|
| 9301 | class="cmtt-8"> </span><span
|
|---|
| 9302 | class="cmtt-8"> </span><span
|
|---|
| 9303 | class="cmtt-8"> </span><span
|
|---|
| 9304 | class="cmtt-8"> </span><span
|
|---|
| 9305 | class="cmtt-8"> </span><span
|
|---|
| 9306 | class="cmtt-8"> </span><span
|
|---|
| 9307 | class="cmtt-8"> </span><span
|
|---|
| 9308 | class="cmtt-8"> </span><span
|
|---|
| 9309 | class="cmtt-8"> </span><span
|
|---|
| 9310 | class="cmtt-8"> </span><span
|
|---|
| 9311 | class="cmtt-8"> </span><span
|
|---|
| 9312 | class="cmtt-8"> </span><span
|
|---|
| 9313 | class="cmtt-8"> }</span><span
|
|---|
| 9314 | class="cmtt-8"> else</span><span
|
|---|
| 9315 | class="cmtt-8"> {</span><br class="fancyvrb" /><a
|
|---|
| 9316 | id="x1-111048r10"></a><span
|
|---|
| 9317 | class="cmr-6">10</span>
|
|---|
| 9318 | <br class="fancyvrb" /><a
|
|---|
| 9319 | id="x1-111050r11"></a><span
|
|---|
| 9320 | class="cmr-6">11</span><span
|
|---|
| 9321 | class="cmtt-8"> </span><span
|
|---|
| 9322 | class="cmtt-8"> </span><span
|
|---|
| 9323 | class="cmtt-8"> </span><span
|
|---|
| 9324 | class="cmtt-8"> </span><span
|
|---|
| 9325 | class="cmtt-8"> </span><span
|
|---|
| 9326 | class="cmtt-8"> </span><span
|
|---|
| 9327 | class="cmtt-8"> </span><span
|
|---|
| 9328 | class="cmtt-8"> </span><span
|
|---|
| 9329 | class="cmtt-8"> </span><span
|
|---|
| 9330 | class="cmtt-8"> </span><span
|
|---|
| 9331 | class="cmtt-8"> </span><span
|
|---|
| 9332 | class="cmtt-8"> </span><span
|
|---|
| 9333 | class="cmtt-8"> </span><span
|
|---|
| 9334 | class="cmtt-8"> </span><span
|
|---|
| 9335 | class="cmtt-8"> </span><span
|
|---|
| 9336 | class="cmtt-8"> </span><span
|
|---|
| 9337 | class="cmtt-8"> 5)</span><span
|
|---|
| 9338 | class="cmtt-8"> array</span><span
|
|---|
| 9339 | class="cmtt-8"> [residue\_books]</span><span
|
|---|
| 9340 | class="cmtt-8"> element</span><span
|
|---|
| 9341 | class="cmtt-8"> [i][j]</span><span
|
|---|
| 9342 | class="cmtt-8"> =</span><span
|
|---|
| 9343 | class="cmtt-8"> unused</span><br class="fancyvrb" /><a
|
|---|
| 9344 | id="x1-111052r12"></a><span
|
|---|
| 9345 | class="cmr-6">12</span><br class="fancyvrb" /><a
|
|---|
| 9346 | id="x1-111054r13"></a><span
|
|---|
| 9347 | class="cmr-6">13</span><span
|
|---|
| 9348 | class="cmtt-8"> </span><span
|
|---|
| 9349 | class="cmtt-8"> </span><span
|
|---|
| 9350 | class="cmtt-8"> </span><span
|
|---|
| 9351 | class="cmtt-8"> </span><span
|
|---|
| 9352 | class="cmtt-8"> </span><span
|
|---|
| 9353 | class="cmtt-8"> </span><span
|
|---|
| 9354 | class="cmtt-8"> </span><span
|
|---|
| 9355 | class="cmtt-8"> </span><span
|
|---|
| 9356 | class="cmtt-8"> </span><span
|
|---|
| 9357 | class="cmtt-8"> </span><span
|
|---|
| 9358 | class="cmtt-8"> </span><span
|
|---|
| 9359 | class="cmtt-8"> </span><span
|
|---|
| 9360 | class="cmtt-8"> </span><span
|
|---|
| 9361 | class="cmtt-8"> </span><span
|
|---|
| 9362 | class="cmtt-8"> }</span><br class="fancyvrb" /><a
|
|---|
| 9363 | id="x1-111056r14"></a><span
|
|---|
| 9364 | class="cmr-6">14</span><span
|
|---|
| 9365 | class="cmtt-8"> </span><span
|
|---|
| 9366 | class="cmtt-8"> </span><span
|
|---|
| 9367 | class="cmtt-8"> </span><span
|
|---|
| 9368 | class="cmtt-8"> </span><span
|
|---|
| 9369 | class="cmtt-8"> </span><span
|
|---|
| 9370 | class="cmtt-8"> </span><span
|
|---|
| 9371 | class="cmtt-8"> </span><span
|
|---|
| 9372 | class="cmtt-8"> </span><span
|
|---|
| 9373 | class="cmtt-8"> </span><span
|
|---|
| 9374 | class="cmtt-8"> }</span><br class="fancyvrb" /><a
|
|---|
| 9375 | id="x1-111058r15"></a><span
|
|---|
| 9376 | class="cmr-6">15</span><span
|
|---|
| 9377 | class="cmtt-8"> </span><span
|
|---|
| 9378 | class="cmtt-8"> </span><span
|
|---|
| 9379 | class="cmtt-8"> </span><span
|
|---|
| 9380 | class="cmtt-8"> </span><span
|
|---|
| 9381 | class="cmtt-8"> </span><span
|
|---|
| 9382 | class="cmtt-8"> }</span><br class="fancyvrb" /><a
|
|---|
| 9383 | id="x1-111060r16"></a><span
|
|---|
| 9384 | class="cmr-6">16</span><br class="fancyvrb" /><a
|
|---|
| 9385 | id="x1-111062r17"></a><span
|
|---|
| 9386 | class="cmr-6">17</span><span
|
|---|
| 9387 | class="cmtt-8"> </span><span
|
|---|
| 9388 | class="cmtt-8"> 6)</span><span
|
|---|
| 9389 | class="cmtt-8"> done</span></div>
|
|---|
| 9390 | <!--l. 230--><p class="noindent" >An end-of-packet condition at any point in header decode renders the stream undecodable.
|
|---|
| 9391 | In addition, any codebook number greater than the maximum numbered codebook
|
|---|
| 9392 | set up in this stream also renders the stream undecodable. All codebooks in array
|
|---|
| 9393 | [residue_books] are required to have a value mapping. The presence of codebook in array
|
|---|
| 9394 | [residue_books] without a value mapping (maptype equals zero) renders the stream
|
|---|
| 9395 | undecodable.
|
|---|
| 9396 | <!--l. 240--><p class="noindent" >
|
|---|
| 9397 | <h5 class="subsubsectionHead"><span class="titlemark">8.6.2. </span> <a
|
|---|
| 9398 | id="x1-1120008.6.2"></a>packet decode</h5>
|
|---|
| 9399 | <!--l. 242--><p class="noindent" >Format 0 and 1 packet decode is identical except for specific partition interleave. Format 2 packet
|
|---|
| 9400 | decode can be built out of the format 1 decode process. Thus we describe first the decode
|
|---|
| 9401 | infrastructure identical to all three formats.
|
|---|
| 9402 | <!--l. 247--><p class="noindent" >In addition to configuration information, the residue decode process is passed the number of
|
|---|
| 9403 | vectors in the submap bundle and a vector of flags indicating if any of the vectors are not to be
|
|---|
| 9404 | decoded. If the passed in number of vectors is 3 and vector number 1 is marked ’do not decode’,
|
|---|
| 9405 | decode skips vector 1 during the decode loop. However, even ’do not decode’ vectors are
|
|---|
| 9406 | allocated and zeroed.
|
|---|
| 9407 | <!--l. 254--><p class="noindent" >Depending on the values of <span
|
|---|
| 9408 | class="cmtt-12">[residue</span><span
|
|---|
| 9409 | class="cmtt-12">_begin] </span>and <span
|
|---|
| 9410 | class="cmtt-12">[residue</span><span
|
|---|
| 9411 | class="cmtt-12">_end]</span>, it is obvious that the
|
|---|
| 9412 | encoded portion of a residue vector may be the entire possible residue vector or some other strict
|
|---|
| 9413 | subset of the actual residue vector size with zero padding at either uncoded end. However, it is
|
|---|
| 9414 | also possible to set <span
|
|---|
| 9415 | class="cmtt-12">[residue</span><span
|
|---|
| 9416 | class="cmtt-12">_begin] </span>and <span
|
|---|
| 9417 | class="cmtt-12">[residue</span><span
|
|---|
| 9418 | class="cmtt-12">_end] </span>to specify a range partially or wholly
|
|---|
| 9419 |
|
|---|
| 9420 |
|
|---|
| 9421 |
|
|---|
| 9422 | beyond the maximum vector size. Before beginning residue decode, limit <span
|
|---|
| 9423 | class="cmtt-12">[residue</span><span
|
|---|
| 9424 | class="cmtt-12">_begin]</span>
|
|---|
| 9425 | and <span
|
|---|
| 9426 | class="cmtt-12">[residue</span><span
|
|---|
| 9427 | class="cmtt-12">_end] </span>to the maximum possible vector size as follows. We assume that
|
|---|
| 9428 | the number of vectors being encoded, <span
|
|---|
| 9429 | class="cmtt-12">[ch] </span>is provided by the higher level decoding
|
|---|
| 9430 | process.
|
|---|
| 9431 | <!--l. 268--><p class="noindent" >
|
|---|
| 9432 | <div class="fancyvrb" id="fancyvrb38"><a
|
|---|
| 9433 | id="x1-112002r1"></a><span
|
|---|
| 9434 | class="cmr-6">1</span><span
|
|---|
| 9435 | class="cmtt-8"> </span><span
|
|---|
| 9436 | class="cmtt-8"> 1)</span><span
|
|---|
| 9437 | class="cmtt-8"> [actual\_size]</span><span
|
|---|
| 9438 | class="cmtt-8"> =</span><span
|
|---|
| 9439 | class="cmtt-8"> current</span><span
|
|---|
| 9440 | class="cmtt-8"> blocksize/2;</span><br class="fancyvrb" /><a
|
|---|
| 9441 | id="x1-112004r2"></a><span
|
|---|
| 9442 | class="cmr-6">2</span><span
|
|---|
| 9443 | class="cmtt-8"> </span><span
|
|---|
| 9444 | class="cmtt-8"> 2)</span><span
|
|---|
| 9445 | class="cmtt-8"> if</span><span
|
|---|
| 9446 | class="cmtt-8"> residue</span><span
|
|---|
| 9447 | class="cmtt-8"> encoding</span><span
|
|---|
| 9448 | class="cmtt-8"> is</span><span
|
|---|
| 9449 | class="cmtt-8"> format</span><span
|
|---|
| 9450 | class="cmtt-8"> 2</span><br class="fancyvrb" /><a
|
|---|
| 9451 | id="x1-112006r3"></a><span
|
|---|
| 9452 | class="cmr-6">3</span><span
|
|---|
| 9453 | class="cmtt-8"> </span><span
|
|---|
| 9454 | class="cmtt-8"> </span><span
|
|---|
| 9455 | class="cmtt-8"> </span><span
|
|---|
| 9456 | class="cmtt-8"> </span><span
|
|---|
| 9457 | class="cmtt-8"> </span><span
|
|---|
| 9458 | class="cmtt-8"> </span><span
|
|---|
| 9459 | class="cmtt-8"> 3)</span><span
|
|---|
| 9460 | class="cmtt-8"> [actual\_size]</span><span
|
|---|
| 9461 | class="cmtt-8"> =</span><span
|
|---|
| 9462 | class="cmtt-8"> [actual\_size]</span><span
|
|---|
| 9463 | class="cmtt-8"> *</span><span
|
|---|
| 9464 | class="cmtt-8"> [ch];</span>
|
|---|
| 9465 | <br class="fancyvrb" /><a
|
|---|
| 9466 | id="x1-112008r4"></a><span
|
|---|
| 9467 | class="cmr-6">4</span><span
|
|---|
| 9468 | class="cmtt-8"> </span><span
|
|---|
| 9469 | class="cmtt-8"> 4)</span><span
|
|---|
| 9470 | class="cmtt-8"> [limit\_residue\_begin]</span><span
|
|---|
| 9471 | class="cmtt-8"> =</span><span
|
|---|
| 9472 | class="cmtt-8"> minimum</span><span
|
|---|
| 9473 | class="cmtt-8"> of</span><span
|
|---|
| 9474 | class="cmtt-8"> ([residue\_begin],[actual\_size]);</span><br class="fancyvrb" /><a
|
|---|
| 9475 | id="x1-112010r5"></a><span
|
|---|
| 9476 | class="cmr-6">5</span><span
|
|---|
| 9477 | class="cmtt-8"> </span><span
|
|---|
| 9478 | class="cmtt-8"> 5)</span><span
|
|---|
| 9479 | class="cmtt-8"> [limit\_residue\_end]</span><span
|
|---|
| 9480 | class="cmtt-8"> =</span><span
|
|---|
| 9481 | class="cmtt-8"> minimum</span><span
|
|---|
| 9482 | class="cmtt-8"> of</span><span
|
|---|
| 9483 | class="cmtt-8"> ([residue\_end],[actual\_size]);</span></div>
|
|---|
| 9484 | <!--l. 276--><p class="noindent" >The following convenience values are conceptually useful to clarifying the decode process:
|
|---|
| 9485 | <!--l. 279--><p class="noindent" >
|
|---|
| 9486 | <div class="fancyvrb" id="fancyvrb39"><a
|
|---|
| 9487 | id="x1-112012r1"></a><span
|
|---|
| 9488 | class="cmr-6">1</span><span
|
|---|
| 9489 | class="cmtt-8"> </span><span
|
|---|
| 9490 | class="cmtt-8"> 1)</span><span
|
|---|
| 9491 | class="cmtt-8"> [classwords\_per\_codeword]</span><span
|
|---|
| 9492 | class="cmtt-8"> =</span><span
|
|---|
| 9493 | class="cmtt-8"> [codebook\_dimensions]</span><span
|
|---|
| 9494 | class="cmtt-8"> value</span><span
|
|---|
| 9495 | class="cmtt-8"> of</span><span
|
|---|
| 9496 | class="cmtt-8"> codebook</span><span
|
|---|
| 9497 | class="cmtt-8"> [residue\_classbook]</span>
|
|---|
| 9498 | <br class="fancyvrb" /><a
|
|---|
| 9499 | id="x1-112014r2"></a><span
|
|---|
| 9500 | class="cmr-6">2</span><span
|
|---|
| 9501 | class="cmtt-8"> </span><span
|
|---|
| 9502 | class="cmtt-8"> 2)</span><span
|
|---|
| 9503 | class="cmtt-8"> [n\_to\_read]</span><span
|
|---|
| 9504 | class="cmtt-8"> =</span><span
|
|---|
| 9505 | class="cmtt-8"> [limit\_residue\_end]</span><span
|
|---|
| 9506 | class="cmtt-8"> -</span><span
|
|---|
| 9507 | class="cmtt-8"> [limit\_residue\_begin]</span><br class="fancyvrb" /><a
|
|---|
| 9508 | id="x1-112016r3"></a><span
|
|---|
| 9509 | class="cmr-6">3</span><span
|
|---|
| 9510 | class="cmtt-8"> </span><span
|
|---|
| 9511 | class="cmtt-8"> 3)</span><span
|
|---|
| 9512 | class="cmtt-8"> [partitions\_to\_read]</span><span
|
|---|
| 9513 | class="cmtt-8"> =</span><span
|
|---|
| 9514 | class="cmtt-8"> [n\_to\_read]</span><span
|
|---|
| 9515 | class="cmtt-8"> /</span><span
|
|---|
| 9516 | class="cmtt-8"> [residue\_partition\_size]</span></div>
|
|---|
| 9517 | <!--l. 285--><p class="noindent" >Packet decode proceeds as follows, matching the description offered earlier in the document.
|
|---|
| 9518 | <div class="fancyvrb" id="fancyvrb40"><a
|
|---|
| 9519 | id="x1-112018r1"></a><span
|
|---|
| 9520 | class="cmr-6">1</span><span
|
|---|
| 9521 | class="cmtt-8"> </span><span
|
|---|
| 9522 | class="cmtt-8"> 1)</span><span
|
|---|
| 9523 | class="cmtt-8"> allocate</span><span
|
|---|
| 9524 | class="cmtt-8"> and</span><span
|
|---|
| 9525 | class="cmtt-8"> zero</span><span
|
|---|
| 9526 | class="cmtt-8"> all</span><span
|
|---|
| 9527 | class="cmtt-8"> vectors</span><span
|
|---|
| 9528 | class="cmtt-8"> that</span><span
|
|---|
| 9529 | class="cmtt-8"> will</span><span
|
|---|
| 9530 | class="cmtt-8"> be</span><span
|
|---|
| 9531 | class="cmtt-8"> returned.</span><br class="fancyvrb" /><a
|
|---|
| 9532 | id="x1-112020r2"></a><span
|
|---|
| 9533 | class="cmr-6">2</span><span
|
|---|
| 9534 | class="cmtt-8"> </span><span
|
|---|
| 9535 | class="cmtt-8"> 2)</span><span
|
|---|
| 9536 | class="cmtt-8"> if</span><span
|
|---|
| 9537 | class="cmtt-8"> ([n\_to\_read]</span><span
|
|---|
| 9538 | class="cmtt-8"> is</span><span
|
|---|
| 9539 | class="cmtt-8"> zero),</span><span
|
|---|
| 9540 | class="cmtt-8"> stop;</span><span
|
|---|
| 9541 | class="cmtt-8"> there</span><span
|
|---|
| 9542 | class="cmtt-8"> is</span><span
|
|---|
| 9543 | class="cmtt-8"> no</span><span
|
|---|
| 9544 | class="cmtt-8"> residue</span><span
|
|---|
| 9545 | class="cmtt-8"> to</span><span
|
|---|
| 9546 | class="cmtt-8"> decode.</span>
|
|---|
| 9547 | <br class="fancyvrb" /><a
|
|---|
| 9548 | id="x1-112022r3"></a><span
|
|---|
| 9549 | class="cmr-6">3</span><span
|
|---|
| 9550 | class="cmtt-8"> </span><span
|
|---|
| 9551 | class="cmtt-8"> 3)</span><span
|
|---|
| 9552 | class="cmtt-8"> iterate</span><span
|
|---|
| 9553 | class="cmtt-8"> [pass]</span><span
|
|---|
| 9554 | class="cmtt-8"> over</span><span
|
|---|
| 9555 | class="cmtt-8"> the</span><span
|
|---|
| 9556 | class="cmtt-8"> range</span><span
|
|---|
| 9557 | class="cmtt-8"> 0</span><span
|
|---|
| 9558 | class="cmtt-8"> ...</span><span
|
|---|
| 9559 | class="cmtt-8"> 7</span><span
|
|---|
| 9560 | class="cmtt-8"> {</span><br class="fancyvrb" /><a
|
|---|
| 9561 | id="x1-112024r4"></a><span
|
|---|
| 9562 | class="cmr-6">4</span><br class="fancyvrb" /><a
|
|---|
| 9563 | id="x1-112026r5"></a><span
|
|---|
| 9564 | class="cmr-6">5</span><span
|
|---|
| 9565 | class="cmtt-8"> </span><span
|
|---|
| 9566 | class="cmtt-8"> </span><span
|
|---|
| 9567 | class="cmtt-8"> </span><span
|
|---|
| 9568 | class="cmtt-8"> </span><span
|
|---|
| 9569 | class="cmtt-8"> </span><span
|
|---|
| 9570 | class="cmtt-8"> </span><span
|
|---|
| 9571 | class="cmtt-8"> 4)</span><span
|
|---|
| 9572 | class="cmtt-8"> [partition\_count]</span><span
|
|---|
| 9573 | class="cmtt-8"> =</span><span
|
|---|
| 9574 | class="cmtt-8"> 0</span><br class="fancyvrb" /><a
|
|---|
| 9575 | id="x1-112028r6"></a><span
|
|---|
| 9576 | class="cmr-6">6</span>
|
|---|
| 9577 | <br class="fancyvrb" /><a
|
|---|
| 9578 | id="x1-112030r7"></a><span
|
|---|
| 9579 | class="cmr-6">7</span><span
|
|---|
| 9580 | class="cmtt-8"> </span><span
|
|---|
| 9581 | class="cmtt-8"> </span><span
|
|---|
| 9582 | class="cmtt-8"> </span><span
|
|---|
| 9583 | class="cmtt-8"> </span><span
|
|---|
| 9584 | class="cmtt-8"> </span><span
|
|---|
| 9585 | class="cmtt-8"> </span><span
|
|---|
| 9586 | class="cmtt-8"> 5)</span><span
|
|---|
| 9587 | class="cmtt-8"> while</span><span
|
|---|
| 9588 | class="cmtt-8"> [partition\_count]</span><span
|
|---|
| 9589 | class="cmtt-8"> is</span><span
|
|---|
| 9590 | class="cmtt-8"> less</span><span
|
|---|
| 9591 | class="cmtt-8"> than</span><span
|
|---|
| 9592 | class="cmtt-8"> [partitions\_to\_read]</span><br class="fancyvrb" /><a
|
|---|
| 9593 | id="x1-112032r8"></a><span
|
|---|
| 9594 | class="cmr-6">8</span><br class="fancyvrb" /><a
|
|---|
| 9595 | id="x1-112034r9"></a><span
|
|---|
| 9596 | class="cmr-6">9</span><span
|
|---|
| 9597 | class="cmtt-8"> </span><span
|
|---|
| 9598 | class="cmtt-8"> </span><span
|
|---|
| 9599 | class="cmtt-8"> </span><span
|
|---|
| 9600 | class="cmtt-8"> </span><span
|
|---|
| 9601 | class="cmtt-8"> </span><span
|
|---|
| 9602 | class="cmtt-8"> </span><span
|
|---|
| 9603 | class="cmtt-8"> </span><span
|
|---|
| 9604 | class="cmtt-8"> </span><span
|
|---|
| 9605 | class="cmtt-8"> </span><span
|
|---|
| 9606 | class="cmtt-8"> </span><span
|
|---|
| 9607 | class="cmtt-8"> </span><span
|
|---|
| 9608 | class="cmtt-8"> 6)</span><span
|
|---|
| 9609 | class="cmtt-8"> if</span><span
|
|---|
| 9610 | class="cmtt-8"> ([pass]</span><span
|
|---|
| 9611 | class="cmtt-8"> is</span><span
|
|---|
| 9612 | class="cmtt-8"> zero)</span><span
|
|---|
| 9613 | class="cmtt-8"> {</span><br class="fancyvrb" /><a
|
|---|
| 9614 | id="x1-112036r10"></a><span
|
|---|
| 9615 | class="cmr-6">10</span>
|
|---|
| 9616 | <br class="fancyvrb" /><a
|
|---|
| 9617 | id="x1-112038r11"></a><span
|
|---|
| 9618 | class="cmr-6">11</span><span
|
|---|
| 9619 | class="cmtt-8"> </span><span
|
|---|
| 9620 | class="cmtt-8"> </span><span
|
|---|
| 9621 | class="cmtt-8"> </span><span
|
|---|
| 9622 | class="cmtt-8"> </span><span
|
|---|
| 9623 | class="cmtt-8"> </span><span
|
|---|
| 9624 | class="cmtt-8"> </span><span
|
|---|
| 9625 | class="cmtt-8"> </span><span
|
|---|
| 9626 | class="cmtt-8"> </span><span
|
|---|
| 9627 | class="cmtt-8"> </span><span
|
|---|
| 9628 | class="cmtt-8"> </span><span
|
|---|
| 9629 | class="cmtt-8"> </span><span
|
|---|
| 9630 | class="cmtt-8"> </span><span
|
|---|
| 9631 | class="cmtt-8"> </span><span
|
|---|
| 9632 | class="cmtt-8"> </span><span
|
|---|
| 9633 | class="cmtt-8"> </span><span
|
|---|
| 9634 | class="cmtt-8"> </span><span
|
|---|
| 9635 | class="cmtt-8"> 7)</span><span
|
|---|
| 9636 | class="cmtt-8"> iterate</span><span
|
|---|
| 9637 | class="cmtt-8"> [j]</span><span
|
|---|
| 9638 | class="cmtt-8"> over</span><span
|
|---|
| 9639 | class="cmtt-8"> the</span><span
|
|---|
| 9640 | class="cmtt-8"> range</span><span
|
|---|
| 9641 | class="cmtt-8"> 0</span><span
|
|---|
| 9642 | class="cmtt-8"> ..</span><span
|
|---|
| 9643 | class="cmtt-8"> [ch]-1</span><span
|
|---|
| 9644 | class="cmtt-8"> {</span><br class="fancyvrb" /><a
|
|---|
| 9645 | id="x1-112040r12"></a><span
|
|---|
| 9646 | class="cmr-6">12</span><br class="fancyvrb" /><a
|
|---|
| 9647 | id="x1-112042r13"></a><span
|
|---|
| 9648 | class="cmr-6">13</span><span
|
|---|
| 9649 | class="cmtt-8"> </span><span
|
|---|
| 9650 | class="cmtt-8"> </span><span
|
|---|
| 9651 | class="cmtt-8"> </span><span
|
|---|
| 9652 | class="cmtt-8"> </span><span
|
|---|
| 9653 | class="cmtt-8"> </span><span
|
|---|
| 9654 | class="cmtt-8"> </span><span
|
|---|
| 9655 | class="cmtt-8"> </span><span
|
|---|
| 9656 | class="cmtt-8"> </span><span
|
|---|
| 9657 | class="cmtt-8"> </span><span
|
|---|
| 9658 | class="cmtt-8"> </span><span
|
|---|
| 9659 | class="cmtt-8"> </span><span
|
|---|
| 9660 | class="cmtt-8"> </span><span
|
|---|
| 9661 | class="cmtt-8"> </span><span
|
|---|
| 9662 | class="cmtt-8"> </span><span
|
|---|
| 9663 | class="cmtt-8"> </span><span
|
|---|
| 9664 | class="cmtt-8"> </span><span
|
|---|
| 9665 | class="cmtt-8"> </span><span
|
|---|
| 9666 | class="cmtt-8"> </span><span
|
|---|
| 9667 | class="cmtt-8"> </span><span
|
|---|
| 9668 | class="cmtt-8"> </span><span
|
|---|
| 9669 | class="cmtt-8"> </span><span
|
|---|
| 9670 | class="cmtt-8"> 8)</span><span
|
|---|
| 9671 | class="cmtt-8"> if</span><span
|
|---|
| 9672 | class="cmtt-8"> vector</span><span
|
|---|
| 9673 | class="cmtt-8"> [j]</span><span
|
|---|
| 9674 | class="cmtt-8"> is</span><span
|
|---|
| 9675 | class="cmtt-8"> not</span><span
|
|---|
| 9676 | class="cmtt-8"> marked</span><span
|
|---|
| 9677 | class="cmtt-8"> ’do</span><span
|
|---|
| 9678 | class="cmtt-8"> not</span><span
|
|---|
| 9679 | class="cmtt-8"> decode’</span><span
|
|---|
| 9680 | class="cmtt-8"> {</span><br class="fancyvrb" /><a
|
|---|
| 9681 | id="x1-112044r14"></a><span
|
|---|
| 9682 | class="cmr-6">14</span>
|
|---|
| 9683 | <br class="fancyvrb" /><a
|
|---|
| 9684 | id="x1-112046r15"></a><span
|
|---|
| 9685 | class="cmr-6">15</span><span
|
|---|
| 9686 | class="cmtt-8"> </span><span
|
|---|
| 9687 | class="cmtt-8"> </span><span
|
|---|
| 9688 | class="cmtt-8"> </span><span
|
|---|
| 9689 | class="cmtt-8"> </span><span
|
|---|
| 9690 | class="cmtt-8"> </span><span
|
|---|
| 9691 | class="cmtt-8"> </span><span
|
|---|
| 9692 | class="cmtt-8"> </span><span
|
|---|
| 9693 | class="cmtt-8"> </span><span
|
|---|
| 9694 | class="cmtt-8"> </span><span
|
|---|
| 9695 | class="cmtt-8"> </span><span
|
|---|
| 9696 | class="cmtt-8"> </span><span
|
|---|
| 9697 | class="cmtt-8"> </span><span
|
|---|
| 9698 | class="cmtt-8"> </span><span
|
|---|
| 9699 | class="cmtt-8"> </span><span
|
|---|
| 9700 | class="cmtt-8"> </span><span
|
|---|
| 9701 | class="cmtt-8"> </span><span
|
|---|
| 9702 | class="cmtt-8"> </span><span
|
|---|
| 9703 | class="cmtt-8"> </span><span
|
|---|
| 9704 | class="cmtt-8"> </span><span
|
|---|
| 9705 | class="cmtt-8"> </span><span
|
|---|
| 9706 | class="cmtt-8"> </span><span
|
|---|
| 9707 | class="cmtt-8"> </span><span
|
|---|
| 9708 | class="cmtt-8"> </span><span
|
|---|
| 9709 | class="cmtt-8"> </span><span
|
|---|
| 9710 | class="cmtt-8"> </span><span
|
|---|
| 9711 | class="cmtt-8"> </span><span
|
|---|
| 9712 | class="cmtt-8"> 9)</span><span
|
|---|
| 9713 | class="cmtt-8"> [temp]</span><span
|
|---|
| 9714 | class="cmtt-8"> =</span><span
|
|---|
| 9715 | class="cmtt-8"> read</span><span
|
|---|
| 9716 | class="cmtt-8"> from</span><span
|
|---|
| 9717 | class="cmtt-8"> packet</span><span
|
|---|
| 9718 | class="cmtt-8"> using</span><span
|
|---|
| 9719 | class="cmtt-8"> codebook</span><span
|
|---|
| 9720 | class="cmtt-8"> [residue\_classbook]</span><span
|
|---|
| 9721 | class="cmtt-8"> in</span><span
|
|---|
| 9722 | class="cmtt-8"> scalar</span><span
|
|---|
| 9723 | class="cmtt-8"> context</span>
|
|---|
| 9724 | <br class="fancyvrb" /><a
|
|---|
| 9725 | id="x1-112048r16"></a><span
|
|---|
| 9726 | class="cmr-6">16</span><span
|
|---|
| 9727 | class="cmtt-8"> </span><span
|
|---|
| 9728 | class="cmtt-8"> </span><span
|
|---|
| 9729 | class="cmtt-8"> </span><span
|
|---|
| 9730 | class="cmtt-8"> </span><span
|
|---|
| 9731 | class="cmtt-8"> </span><span
|
|---|
| 9732 | class="cmtt-8"> </span><span
|
|---|
| 9733 | class="cmtt-8"> </span><span
|
|---|
| 9734 | class="cmtt-8"> </span><span
|
|---|
| 9735 | class="cmtt-8"> </span><span
|
|---|
| 9736 | class="cmtt-8"> </span><span
|
|---|
| 9737 | class="cmtt-8"> </span><span
|
|---|
| 9738 | class="cmtt-8"> </span><span
|
|---|
| 9739 | class="cmtt-8"> </span><span
|
|---|
| 9740 | class="cmtt-8"> </span><span
|
|---|
| 9741 | class="cmtt-8"> </span><span
|
|---|
| 9742 | class="cmtt-8"> </span><span
|
|---|
| 9743 | class="cmtt-8"> </span><span
|
|---|
| 9744 | class="cmtt-8"> </span><span
|
|---|
| 9745 | class="cmtt-8"> </span><span
|
|---|
| 9746 | class="cmtt-8"> </span><span
|
|---|
| 9747 | class="cmtt-8"> </span><span
|
|---|
| 9748 | class="cmtt-8"> </span><span
|
|---|
| 9749 | class="cmtt-8"> </span><span
|
|---|
| 9750 | class="cmtt-8"> </span><span
|
|---|
| 9751 | class="cmtt-8"> </span><span
|
|---|
| 9752 | class="cmtt-8"> 10)</span><span
|
|---|
| 9753 | class="cmtt-8"> iterate</span><span
|
|---|
| 9754 | class="cmtt-8"> [i]</span><span
|
|---|
| 9755 | class="cmtt-8"> descending</span><span
|
|---|
| 9756 | class="cmtt-8"> over</span><span
|
|---|
| 9757 | class="cmtt-8"> the</span><span
|
|---|
| 9758 | class="cmtt-8"> range</span><span
|
|---|
| 9759 | class="cmtt-8"> [classwords\_per\_codeword]-1</span><span
|
|---|
| 9760 | class="cmtt-8"> ...</span><span
|
|---|
| 9761 | class="cmtt-8"> 0</span><span
|
|---|
| 9762 | class="cmtt-8"> {</span><br class="fancyvrb" /><a
|
|---|
| 9763 | id="x1-112050r17"></a><span
|
|---|
| 9764 | class="cmr-6">17</span>
|
|---|
| 9765 | <br class="fancyvrb" /><a
|
|---|
| 9766 | id="x1-112052r18"></a><span
|
|---|
| 9767 | class="cmr-6">18</span><span
|
|---|
| 9768 | class="cmtt-8"> </span><span
|
|---|
| 9769 | class="cmtt-8"> </span><span
|
|---|
| 9770 | class="cmtt-8"> </span><span
|
|---|
| 9771 | class="cmtt-8"> </span><span
|
|---|
| 9772 | class="cmtt-8"> </span><span
|
|---|
| 9773 | class="cmtt-8"> </span><span
|
|---|
| 9774 | class="cmtt-8"> </span><span
|
|---|
| 9775 | class="cmtt-8"> </span><span
|
|---|
| 9776 | class="cmtt-8"> </span><span
|
|---|
| 9777 | class="cmtt-8"> </span><span
|
|---|
| 9778 | class="cmtt-8"> </span><span
|
|---|
| 9779 | class="cmtt-8"> </span><span
|
|---|
| 9780 | class="cmtt-8"> </span><span
|
|---|
| 9781 | class="cmtt-8"> </span><span
|
|---|
| 9782 | class="cmtt-8"> </span><span
|
|---|
| 9783 | class="cmtt-8"> </span><span
|
|---|
| 9784 | class="cmtt-8"> </span><span
|
|---|
| 9785 | class="cmtt-8"> </span><span
|
|---|
| 9786 | class="cmtt-8"> </span><span
|
|---|
| 9787 | class="cmtt-8"> </span><span
|
|---|
| 9788 | class="cmtt-8"> </span><span
|
|---|
| 9789 | class="cmtt-8"> </span><span
|
|---|
| 9790 | class="cmtt-8"> </span><span
|
|---|
| 9791 | class="cmtt-8"> </span><span
|
|---|
| 9792 | class="cmtt-8"> </span><span
|
|---|
| 9793 | class="cmtt-8"> </span><span
|
|---|
| 9794 | class="cmtt-8"> </span><span
|
|---|
| 9795 | class="cmtt-8"> </span><span
|
|---|
| 9796 | class="cmtt-8"> </span><span
|
|---|
| 9797 | class="cmtt-8"> </span><span
|
|---|
| 9798 | class="cmtt-8"> 11)</span><span
|
|---|
| 9799 | class="cmtt-8"> array</span><span
|
|---|
| 9800 | class="cmtt-8"> [classifications]</span><span
|
|---|
| 9801 | class="cmtt-8"> element</span><span
|
|---|
| 9802 | class="cmtt-8"> [j],([i]+[partition\_count])</span><span
|
|---|
| 9803 | class="cmtt-8"> =</span>
|
|---|
| 9804 | <br class="fancyvrb" /><a
|
|---|
| 9805 | id="x1-112054r19"></a><span
|
|---|
| 9806 | class="cmr-6">19</span><span
|
|---|
| 9807 | class="cmtt-8"> </span><span
|
|---|
| 9808 | class="cmtt-8"> </span><span
|
|---|
| 9809 | class="cmtt-8"> </span><span
|
|---|
| 9810 | class="cmtt-8"> </span><span
|
|---|
| 9811 | class="cmtt-8"> </span><span
|
|---|
| 9812 | class="cmtt-8"> </span><span
|
|---|
| 9813 | class="cmtt-8"> </span><span
|
|---|
| 9814 | class="cmtt-8"> </span><span
|
|---|
| 9815 | class="cmtt-8"> </span><span
|
|---|
| 9816 | class="cmtt-8"> </span><span
|
|---|
| 9817 | class="cmtt-8"> </span><span
|
|---|
| 9818 | class="cmtt-8"> </span><span
|
|---|
| 9819 | class="cmtt-8"> </span><span
|
|---|
| 9820 | class="cmtt-8"> </span><span
|
|---|
| 9821 | class="cmtt-8"> </span><span
|
|---|
| 9822 | class="cmtt-8"> </span><span
|
|---|
| 9823 | class="cmtt-8"> </span><span
|
|---|
| 9824 | class="cmtt-8"> </span><span
|
|---|
| 9825 | class="cmtt-8"> </span><span
|
|---|
| 9826 | class="cmtt-8"> </span><span
|
|---|
| 9827 | class="cmtt-8"> </span><span
|
|---|
| 9828 | class="cmtt-8"> </span><span
|
|---|
| 9829 | class="cmtt-8"> </span><span
|
|---|
| 9830 | class="cmtt-8"> </span><span
|
|---|
| 9831 | class="cmtt-8"> </span><span
|
|---|
| 9832 | class="cmtt-8"> </span><span
|
|---|
| 9833 | class="cmtt-8"> </span><span
|
|---|
| 9834 | class="cmtt-8"> </span><span
|
|---|
| 9835 | class="cmtt-8"> </span><span
|
|---|
| 9836 | class="cmtt-8"> </span><span
|
|---|
| 9837 | class="cmtt-8"> </span><span
|
|---|
| 9838 | class="cmtt-8"> </span><span
|
|---|
| 9839 | class="cmtt-8"> </span><span
|
|---|
| 9840 | class="cmtt-8"> </span><span
|
|---|
| 9841 | class="cmtt-8"> [temp]</span><span
|
|---|
| 9842 | class="cmtt-8"> integer</span><span
|
|---|
| 9843 | class="cmtt-8"> modulo</span><span
|
|---|
| 9844 | class="cmtt-8"> [residue\_classifications]</span>
|
|---|
| 9845 | <br class="fancyvrb" /><a
|
|---|
| 9846 | id="x1-112056r20"></a><span
|
|---|
| 9847 | class="cmr-6">20</span><span
|
|---|
| 9848 | class="cmtt-8"> </span><span
|
|---|
| 9849 | class="cmtt-8"> </span><span
|
|---|
| 9850 | class="cmtt-8"> </span><span
|
|---|
| 9851 | class="cmtt-8"> </span><span
|
|---|
| 9852 | class="cmtt-8"> </span><span
|
|---|
| 9853 | class="cmtt-8"> </span><span
|
|---|
| 9854 | class="cmtt-8"> </span><span
|
|---|
| 9855 | class="cmtt-8"> </span><span
|
|---|
| 9856 | class="cmtt-8"> </span><span
|
|---|
| 9857 | class="cmtt-8"> </span><span
|
|---|
| 9858 | class="cmtt-8"> </span><span
|
|---|
| 9859 | class="cmtt-8"> </span><span
|
|---|
| 9860 | class="cmtt-8"> </span><span
|
|---|
| 9861 | class="cmtt-8"> </span><span
|
|---|
| 9862 | class="cmtt-8"> </span><span
|
|---|
| 9863 | class="cmtt-8"> </span><span
|
|---|
| 9864 | class="cmtt-8"> </span><span
|
|---|
| 9865 | class="cmtt-8"> </span><span
|
|---|
| 9866 | class="cmtt-8"> </span><span
|
|---|
| 9867 | class="cmtt-8"> </span><span
|
|---|
| 9868 | class="cmtt-8"> </span><span
|
|---|
| 9869 | class="cmtt-8"> </span><span
|
|---|
| 9870 | class="cmtt-8"> </span><span
|
|---|
| 9871 | class="cmtt-8"> </span><span
|
|---|
| 9872 | class="cmtt-8"> </span><span
|
|---|
| 9873 | class="cmtt-8"> </span><span
|
|---|
| 9874 | class="cmtt-8"> </span><span
|
|---|
| 9875 | class="cmtt-8"> </span><span
|
|---|
| 9876 | class="cmtt-8"> </span><span
|
|---|
| 9877 | class="cmtt-8"> </span><span
|
|---|
| 9878 | class="cmtt-8"> 12)</span><span
|
|---|
| 9879 | class="cmtt-8"> [temp]</span><span
|
|---|
| 9880 | class="cmtt-8"> =</span><span
|
|---|
| 9881 | class="cmtt-8"> [temp]</span><span
|
|---|
| 9882 | class="cmtt-8"> /</span><span
|
|---|
| 9883 | class="cmtt-8"> [residue\_classifications]</span><span
|
|---|
| 9884 | class="cmtt-8"> using</span><span
|
|---|
| 9885 | class="cmtt-8"> integer</span><span
|
|---|
| 9886 | class="cmtt-8"> division</span><br class="fancyvrb" /><a
|
|---|
| 9887 | id="x1-112058r21"></a><span
|
|---|
| 9888 | class="cmr-6">21</span>
|
|---|
| 9889 | <br class="fancyvrb" /><a
|
|---|
| 9890 | id="x1-112060r22"></a><span
|
|---|
| 9891 | class="cmr-6">22</span><span
|
|---|
| 9892 | class="cmtt-8"> </span><span
|
|---|
| 9893 | class="cmtt-8"> </span><span
|
|---|
| 9894 | class="cmtt-8"> </span><span
|
|---|
| 9895 | class="cmtt-8"> </span><span
|
|---|
| 9896 | class="cmtt-8"> </span><span
|
|---|
| 9897 | class="cmtt-8"> </span><span
|
|---|
| 9898 | class="cmtt-8"> </span><span
|
|---|
| 9899 | class="cmtt-8"> </span><span
|
|---|
| 9900 | class="cmtt-8"> </span><span
|
|---|
| 9901 | class="cmtt-8"> </span><span
|
|---|
| 9902 | class="cmtt-8"> </span><span
|
|---|
| 9903 | class="cmtt-8"> </span><span
|
|---|
| 9904 | class="cmtt-8"> </span><span
|
|---|
| 9905 | class="cmtt-8"> </span><span
|
|---|
| 9906 | class="cmtt-8"> </span><span
|
|---|
| 9907 | class="cmtt-8"> </span><span
|
|---|
| 9908 | class="cmtt-8"> </span><span
|
|---|
| 9909 | class="cmtt-8"> </span><span
|
|---|
| 9910 | class="cmtt-8"> </span><span
|
|---|
| 9911 | class="cmtt-8"> </span><span
|
|---|
| 9912 | class="cmtt-8"> </span><span
|
|---|
| 9913 | class="cmtt-8"> </span><span
|
|---|
| 9914 | class="cmtt-8"> </span><span
|
|---|
| 9915 | class="cmtt-8"> </span><span
|
|---|
| 9916 | class="cmtt-8"> </span><span
|
|---|
| 9917 | class="cmtt-8"> </span><span
|
|---|
| 9918 | class="cmtt-8"> </span><span
|
|---|
| 9919 | class="cmtt-8"> </span><span
|
|---|
| 9920 | class="cmtt-8"> </span><span
|
|---|
| 9921 | class="cmtt-8"> }</span><br class="fancyvrb" /><a
|
|---|
| 9922 | id="x1-112062r23"></a><span
|
|---|
| 9923 | class="cmr-6">23</span><br class="fancyvrb" /><a
|
|---|
| 9924 | id="x1-112064r24"></a><span
|
|---|
| 9925 | class="cmr-6">24</span><span
|
|---|
| 9926 | class="cmtt-8"> </span><span
|
|---|
| 9927 | class="cmtt-8"> </span><span
|
|---|
| 9928 | class="cmtt-8"> </span><span
|
|---|
| 9929 | class="cmtt-8"> </span><span
|
|---|
| 9930 | class="cmtt-8"> </span><span
|
|---|
| 9931 | class="cmtt-8"> </span><span
|
|---|
| 9932 | class="cmtt-8"> </span><span
|
|---|
| 9933 | class="cmtt-8"> </span><span
|
|---|
| 9934 | class="cmtt-8"> </span><span
|
|---|
| 9935 | class="cmtt-8"> </span><span
|
|---|
| 9936 | class="cmtt-8"> </span><span
|
|---|
| 9937 | class="cmtt-8"> </span><span
|
|---|
| 9938 | class="cmtt-8"> </span><span
|
|---|
| 9939 | class="cmtt-8"> </span><span
|
|---|
| 9940 | class="cmtt-8"> </span><span
|
|---|
| 9941 | class="cmtt-8"> </span><span
|
|---|
| 9942 | class="cmtt-8"> </span><span
|
|---|
| 9943 | class="cmtt-8"> </span><span
|
|---|
| 9944 | class="cmtt-8"> </span><span
|
|---|
| 9945 | class="cmtt-8"> </span><span
|
|---|
| 9946 | class="cmtt-8"> </span><span
|
|---|
| 9947 | class="cmtt-8"> </span><span
|
|---|
| 9948 | class="cmtt-8"> </span><span
|
|---|
| 9949 | class="cmtt-8"> </span><span
|
|---|
| 9950 | class="cmtt-8"> }</span><br class="fancyvrb" /><a
|
|---|
| 9951 | id="x1-112066r25"></a><span
|
|---|
| 9952 | class="cmr-6">25</span><br class="fancyvrb" /><a
|
|---|
| 9953 | id="x1-112068r26"></a><span
|
|---|
| 9954 | class="cmr-6">26</span><span
|
|---|
| 9955 | class="cmtt-8"> </span><span
|
|---|
| 9956 | class="cmtt-8"> </span><span
|
|---|
| 9957 | class="cmtt-8"> </span><span
|
|---|
| 9958 | class="cmtt-8"> </span><span
|
|---|
| 9959 | class="cmtt-8"> </span><span
|
|---|
| 9960 | class="cmtt-8"> </span><span
|
|---|
| 9961 | class="cmtt-8"> </span><span
|
|---|
| 9962 | class="cmtt-8"> </span><span
|
|---|
| 9963 | class="cmtt-8"> </span><span
|
|---|
| 9964 | class="cmtt-8"> </span><span
|
|---|
| 9965 | class="cmtt-8"> </span><span
|
|---|
| 9966 | class="cmtt-8"> </span><span
|
|---|
| 9967 | class="cmtt-8"> </span><span
|
|---|
| 9968 | class="cmtt-8"> </span><span
|
|---|
| 9969 | class="cmtt-8"> </span><span
|
|---|
| 9970 | class="cmtt-8"> </span><span
|
|---|
| 9971 | class="cmtt-8"> </span><span
|
|---|
| 9972 | class="cmtt-8"> </span><span
|
|---|
| 9973 | class="cmtt-8"> </span><span
|
|---|
| 9974 | class="cmtt-8"> }</span><br class="fancyvrb" /><a
|
|---|
| 9975 | id="x1-112070r27"></a><span
|
|---|
| 9976 | class="cmr-6">27</span><br class="fancyvrb" /><a
|
|---|
| 9977 | id="x1-112072r28"></a><span
|
|---|
| 9978 | class="cmr-6">28</span><span
|
|---|
| 9979 | class="cmtt-8"> </span><span
|
|---|
| 9980 | class="cmtt-8"> </span><span
|
|---|
| 9981 | class="cmtt-8"> </span><span
|
|---|
| 9982 | class="cmtt-8"> </span><span
|
|---|
| 9983 | class="cmtt-8"> </span><span
|
|---|
| 9984 | class="cmtt-8"> </span><span
|
|---|
| 9985 | class="cmtt-8"> </span><span
|
|---|
| 9986 | class="cmtt-8"> </span><span
|
|---|
| 9987 | class="cmtt-8"> </span><span
|
|---|
| 9988 | class="cmtt-8"> </span><span
|
|---|
| 9989 | class="cmtt-8"> </span><span
|
|---|
| 9990 | class="cmtt-8"> </span><span
|
|---|
| 9991 | class="cmtt-8"> </span><span
|
|---|
| 9992 | class="cmtt-8"> </span><span
|
|---|
| 9993 | class="cmtt-8"> }</span><br class="fancyvrb" /><a
|
|---|
| 9994 | id="x1-112074r29"></a><span
|
|---|
| 9995 | class="cmr-6">29</span>
|
|---|
| 9996 | <br class="fancyvrb" /><a
|
|---|
| 9997 | id="x1-112076r30"></a><span
|
|---|
| 9998 | class="cmr-6">30</span><span
|
|---|
| 9999 | class="cmtt-8"> </span><span
|
|---|
| 10000 | class="cmtt-8"> </span><span
|
|---|
| 10001 | class="cmtt-8"> </span><span
|
|---|
| 10002 | class="cmtt-8"> </span><span
|
|---|
| 10003 | class="cmtt-8"> </span><span
|
|---|
| 10004 | class="cmtt-8"> </span><span
|
|---|
| 10005 | class="cmtt-8"> </span><span
|
|---|
| 10006 | class="cmtt-8"> </span><span
|
|---|
| 10007 | class="cmtt-8"> </span><span
|
|---|
| 10008 | class="cmtt-8"> </span><span
|
|---|
| 10009 | class="cmtt-8"> 13)</span><span
|
|---|
| 10010 | class="cmtt-8"> iterate</span><span
|
|---|
| 10011 | class="cmtt-8"> [i]</span><span
|
|---|
| 10012 | class="cmtt-8"> over</span><span
|
|---|
| 10013 | class="cmtt-8"> the</span><span
|
|---|
| 10014 | class="cmtt-8"> range</span><span
|
|---|
| 10015 | class="cmtt-8"> 0</span><span
|
|---|
| 10016 | class="cmtt-8"> ..</span><span
|
|---|
| 10017 | class="cmtt-8"> ([classwords\_per\_codeword]</span><span
|
|---|
| 10018 | class="cmtt-8"> -</span><span
|
|---|
| 10019 | class="cmtt-8"> 1)</span><span
|
|---|
| 10020 | class="cmtt-8"> while</span><span
|
|---|
| 10021 | class="cmtt-8"> [partition\_count]</span>
|
|---|
| 10022 | <br class="fancyvrb" /><a
|
|---|
| 10023 | id="x1-112078r31"></a><span
|
|---|
| 10024 | class="cmr-6">31</span><span
|
|---|
| 10025 | class="cmtt-8"> </span><span
|
|---|
| 10026 | class="cmtt-8"> </span><span
|
|---|
| 10027 | class="cmtt-8"> </span><span
|
|---|
| 10028 | class="cmtt-8"> </span><span
|
|---|
| 10029 | class="cmtt-8"> </span><span
|
|---|
| 10030 | class="cmtt-8"> </span><span
|
|---|
| 10031 | class="cmtt-8"> </span><span
|
|---|
| 10032 | class="cmtt-8"> </span><span
|
|---|
| 10033 | class="cmtt-8"> </span><span
|
|---|
| 10034 | class="cmtt-8"> </span><span
|
|---|
| 10035 | class="cmtt-8"> </span><span
|
|---|
| 10036 | class="cmtt-8"> </span><span
|
|---|
| 10037 | class="cmtt-8"> </span><span
|
|---|
| 10038 | class="cmtt-8"> </span><span
|
|---|
| 10039 | class="cmtt-8"> is</span><span
|
|---|
| 10040 | class="cmtt-8"> also</span><span
|
|---|
| 10041 | class="cmtt-8"> less</span><span
|
|---|
| 10042 | class="cmtt-8"> than</span><span
|
|---|
| 10043 | class="cmtt-8"> [partitions\_to\_read]</span><span
|
|---|
| 10044 | class="cmtt-8"> {</span><br class="fancyvrb" /><a
|
|---|
| 10045 | id="x1-112080r32"></a><span
|
|---|
| 10046 | class="cmr-6">32</span><br class="fancyvrb" /><a
|
|---|
| 10047 | id="x1-112082r33"></a><span
|
|---|
| 10048 | class="cmr-6">33</span><span
|
|---|
| 10049 | class="cmtt-8"> </span><span
|
|---|
| 10050 | class="cmtt-8"> </span><span
|
|---|
| 10051 | class="cmtt-8"> </span><span
|
|---|
| 10052 | class="cmtt-8"> </span><span
|
|---|
| 10053 | class="cmtt-8"> </span><span
|
|---|
| 10054 | class="cmtt-8"> </span><span
|
|---|
| 10055 | class="cmtt-8"> </span><span
|
|---|
| 10056 | class="cmtt-8"> </span><span
|
|---|
| 10057 | class="cmtt-8"> </span><span
|
|---|
| 10058 | class="cmtt-8"> </span><span
|
|---|
| 10059 | class="cmtt-8"> </span><span
|
|---|
| 10060 | class="cmtt-8"> </span><span
|
|---|
| 10061 | class="cmtt-8"> </span><span
|
|---|
| 10062 | class="cmtt-8"> </span><span
|
|---|
| 10063 | class="cmtt-8"> </span><span
|
|---|
| 10064 | class="cmtt-8"> </span><span
|
|---|
| 10065 | class="cmtt-8"> 14)</span><span
|
|---|
| 10066 | class="cmtt-8"> iterate</span><span
|
|---|
| 10067 | class="cmtt-8"> [j]</span><span
|
|---|
| 10068 | class="cmtt-8"> over</span><span
|
|---|
| 10069 | class="cmtt-8"> the</span><span
|
|---|
| 10070 | class="cmtt-8"> range</span><span
|
|---|
| 10071 | class="cmtt-8"> 0</span><span
|
|---|
| 10072 | class="cmtt-8"> ..</span><span
|
|---|
| 10073 | class="cmtt-8"> [ch]-1</span><span
|
|---|
| 10074 | class="cmtt-8"> {</span><br class="fancyvrb" /><a
|
|---|
| 10075 | id="x1-112084r34"></a><span
|
|---|
| 10076 | class="cmr-6">34</span>
|
|---|
| 10077 | <br class="fancyvrb" /><a
|
|---|
| 10078 | id="x1-112086r35"></a><span
|
|---|
| 10079 | class="cmr-6">35</span><span
|
|---|
| 10080 | class="cmtt-8"> </span><span
|
|---|
| 10081 | class="cmtt-8"> </span><span
|
|---|
| 10082 | class="cmtt-8"> </span><span
|
|---|
| 10083 | class="cmtt-8"> </span><span
|
|---|
| 10084 | class="cmtt-8"> </span><span
|
|---|
| 10085 | class="cmtt-8"> </span><span
|
|---|
| 10086 | class="cmtt-8"> </span><span
|
|---|
| 10087 | class="cmtt-8"> </span><span
|
|---|
| 10088 | class="cmtt-8"> </span><span
|
|---|
| 10089 | class="cmtt-8"> </span><span
|
|---|
| 10090 | class="cmtt-8"> </span><span
|
|---|
| 10091 | class="cmtt-8"> </span><span
|
|---|
| 10092 | class="cmtt-8"> </span><span
|
|---|
| 10093 | class="cmtt-8"> </span><span
|
|---|
| 10094 | class="cmtt-8"> </span><span
|
|---|
| 10095 | class="cmtt-8"> </span><span
|
|---|
| 10096 | class="cmtt-8"> </span><span
|
|---|
| 10097 | class="cmtt-8"> </span><span
|
|---|
| 10098 | class="cmtt-8"> </span><span
|
|---|
| 10099 | class="cmtt-8"> </span><span
|
|---|
| 10100 | class="cmtt-8"> </span><span
|
|---|
| 10101 | class="cmtt-8"> 15)</span><span
|
|---|
| 10102 | class="cmtt-8"> if</span><span
|
|---|
| 10103 | class="cmtt-8"> vector</span><span
|
|---|
| 10104 | class="cmtt-8"> [j]</span><span
|
|---|
| 10105 | class="cmtt-8"> is</span><span
|
|---|
| 10106 | class="cmtt-8"> not</span><span
|
|---|
| 10107 | class="cmtt-8"> marked</span><span
|
|---|
| 10108 | class="cmtt-8"> ’do</span><span
|
|---|
| 10109 | class="cmtt-8"> not</span><span
|
|---|
| 10110 | class="cmtt-8"> decode’</span><span
|
|---|
| 10111 | class="cmtt-8"> {</span><br class="fancyvrb" /><a
|
|---|
| 10112 | id="x1-112088r36"></a><span
|
|---|
| 10113 | class="cmr-6">36</span>
|
|---|
| 10114 | <br class="fancyvrb" /><a
|
|---|
| 10115 | id="x1-112090r37"></a><span
|
|---|
| 10116 | class="cmr-6">37</span><span
|
|---|
| 10117 | class="cmtt-8"> </span><span
|
|---|
| 10118 | class="cmtt-8"> </span><span
|
|---|
| 10119 | class="cmtt-8"> </span><span
|
|---|
| 10120 | class="cmtt-8"> </span><span
|
|---|
| 10121 | class="cmtt-8"> </span><span
|
|---|
| 10122 | class="cmtt-8"> </span><span
|
|---|
| 10123 | class="cmtt-8"> </span><span
|
|---|
| 10124 | class="cmtt-8"> </span><span
|
|---|
| 10125 | class="cmtt-8"> </span><span
|
|---|
| 10126 | class="cmtt-8"> </span><span
|
|---|
| 10127 | class="cmtt-8"> </span><span
|
|---|
| 10128 | class="cmtt-8"> </span><span
|
|---|
| 10129 | class="cmtt-8"> </span><span
|
|---|
| 10130 | class="cmtt-8"> </span><span
|
|---|
| 10131 | class="cmtt-8"> </span><span
|
|---|
| 10132 | class="cmtt-8"> </span><span
|
|---|
| 10133 | class="cmtt-8"> </span><span
|
|---|
| 10134 | class="cmtt-8"> </span><span
|
|---|
| 10135 | class="cmtt-8"> </span><span
|
|---|
| 10136 | class="cmtt-8"> </span><span
|
|---|
| 10137 | class="cmtt-8"> </span><span
|
|---|
| 10138 | class="cmtt-8"> </span><span
|
|---|
| 10139 | class="cmtt-8"> </span><span
|
|---|
| 10140 | class="cmtt-8"> </span><span
|
|---|
| 10141 | class="cmtt-8"> </span><span
|
|---|
| 10142 | class="cmtt-8"> </span><span
|
|---|
| 10143 | class="cmtt-8"> 16)</span><span
|
|---|
| 10144 | class="cmtt-8"> [vqclass]</span><span
|
|---|
| 10145 | class="cmtt-8"> =</span><span
|
|---|
| 10146 | class="cmtt-8"> array</span><span
|
|---|
| 10147 | class="cmtt-8"> [classifications]</span><span
|
|---|
| 10148 | class="cmtt-8"> element</span><span
|
|---|
| 10149 | class="cmtt-8"> [j],[partition\_count]</span>
|
|---|
| 10150 | <br class="fancyvrb" /><a
|
|---|
| 10151 | id="x1-112092r38"></a><span
|
|---|
| 10152 | class="cmr-6">38</span><span
|
|---|
| 10153 | class="cmtt-8"> </span><span
|
|---|
| 10154 | class="cmtt-8"> </span><span
|
|---|
| 10155 | class="cmtt-8"> </span><span
|
|---|
| 10156 | class="cmtt-8"> </span><span
|
|---|
| 10157 | class="cmtt-8"> </span><span
|
|---|
| 10158 | class="cmtt-8"> </span><span
|
|---|
| 10159 | class="cmtt-8"> </span><span
|
|---|
| 10160 | class="cmtt-8"> </span><span
|
|---|
| 10161 | class="cmtt-8"> </span><span
|
|---|
| 10162 | class="cmtt-8"> </span><span
|
|---|
| 10163 | class="cmtt-8"> </span><span
|
|---|
| 10164 | class="cmtt-8"> </span><span
|
|---|
| 10165 | class="cmtt-8"> </span><span
|
|---|
| 10166 | class="cmtt-8"> </span><span
|
|---|
| 10167 | class="cmtt-8"> </span><span
|
|---|
| 10168 | class="cmtt-8"> </span><span
|
|---|
| 10169 | class="cmtt-8"> </span><span
|
|---|
| 10170 | class="cmtt-8"> </span><span
|
|---|
| 10171 | class="cmtt-8"> </span><span
|
|---|
| 10172 | class="cmtt-8"> </span><span
|
|---|
| 10173 | class="cmtt-8"> </span><span
|
|---|
| 10174 | class="cmtt-8"> </span><span
|
|---|
| 10175 | class="cmtt-8"> </span><span
|
|---|
| 10176 | class="cmtt-8"> </span><span
|
|---|
| 10177 | class="cmtt-8"> </span><span
|
|---|
| 10178 | class="cmtt-8"> </span><span
|
|---|
| 10179 | class="cmtt-8"> 17)</span><span
|
|---|
| 10180 | class="cmtt-8"> [vqbook]</span><span
|
|---|
| 10181 | class="cmtt-8"> =</span><span
|
|---|
| 10182 | class="cmtt-8"> array</span><span
|
|---|
| 10183 | class="cmtt-8"> [residue\_books]</span><span
|
|---|
| 10184 | class="cmtt-8"> element</span><span
|
|---|
| 10185 | class="cmtt-8"> [vqclass],[pass]</span><br class="fancyvrb" /><a
|
|---|
| 10186 | id="x1-112094r39"></a><span
|
|---|
| 10187 | class="cmr-6">39</span><span
|
|---|
| 10188 | class="cmtt-8"> </span><span
|
|---|
| 10189 | class="cmtt-8"> </span><span
|
|---|
| 10190 | class="cmtt-8"> </span><span
|
|---|
| 10191 | class="cmtt-8"> </span><span
|
|---|
| 10192 | class="cmtt-8"> </span><span
|
|---|
| 10193 | class="cmtt-8"> </span><span
|
|---|
| 10194 | class="cmtt-8"> </span><span
|
|---|
| 10195 | class="cmtt-8"> </span><span
|
|---|
| 10196 | class="cmtt-8"> </span><span
|
|---|
| 10197 | class="cmtt-8"> </span><span
|
|---|
| 10198 | class="cmtt-8"> </span><span
|
|---|
| 10199 | class="cmtt-8"> </span><span
|
|---|
| 10200 | class="cmtt-8"> </span><span
|
|---|
| 10201 | class="cmtt-8"> </span><span
|
|---|
| 10202 | class="cmtt-8"> </span><span
|
|---|
| 10203 | class="cmtt-8"> </span><span
|
|---|
| 10204 | class="cmtt-8"> </span><span
|
|---|
| 10205 | class="cmtt-8"> </span><span
|
|---|
| 10206 | class="cmtt-8"> </span><span
|
|---|
| 10207 | class="cmtt-8"> </span><span
|
|---|
| 10208 | class="cmtt-8"> </span><span
|
|---|
| 10209 | class="cmtt-8"> </span><span
|
|---|
| 10210 | class="cmtt-8"> </span><span
|
|---|
| 10211 | class="cmtt-8"> </span><span
|
|---|
| 10212 | class="cmtt-8"> </span><span
|
|---|
| 10213 | class="cmtt-8"> </span><span
|
|---|
| 10214 | class="cmtt-8"> 18)</span><span
|
|---|
| 10215 | class="cmtt-8"> if</span><span
|
|---|
| 10216 | class="cmtt-8"> ([vqbook]</span><span
|
|---|
| 10217 | class="cmtt-8"> is</span><span
|
|---|
| 10218 | class="cmtt-8"> not</span><span
|
|---|
| 10219 | class="cmtt-8"> ’unused’)</span><span
|
|---|
| 10220 | class="cmtt-8"> {</span><br class="fancyvrb" /><a
|
|---|
| 10221 | id="x1-112096r40"></a><span
|
|---|
| 10222 | class="cmr-6">40</span>
|
|---|
| 10223 | <br class="fancyvrb" /><a
|
|---|
| 10224 | id="x1-112098r41"></a><span
|
|---|
| 10225 | class="cmr-6">41</span><span
|
|---|
| 10226 | class="cmtt-8"> </span><span
|
|---|
| 10227 | class="cmtt-8"> </span><span
|
|---|
| 10228 | class="cmtt-8"> </span><span
|
|---|
| 10229 | class="cmtt-8"> </span><span
|
|---|
| 10230 | class="cmtt-8"> </span><span
|
|---|
| 10231 | class="cmtt-8"> </span><span
|
|---|
| 10232 | class="cmtt-8"> </span><span
|
|---|
| 10233 | class="cmtt-8"> </span><span
|
|---|
| 10234 | class="cmtt-8"> </span><span
|
|---|
| 10235 | class="cmtt-8"> </span><span
|
|---|
| 10236 | class="cmtt-8"> </span><span
|
|---|
| 10237 | class="cmtt-8"> </span><span
|
|---|
| 10238 | class="cmtt-8"> </span><span
|
|---|
| 10239 | class="cmtt-8"> </span><span
|
|---|
| 10240 | class="cmtt-8"> </span><span
|
|---|
| 10241 | class="cmtt-8"> </span><span
|
|---|
| 10242 | class="cmtt-8"> </span><span
|
|---|
| 10243 | class="cmtt-8"> </span><span
|
|---|
| 10244 | class="cmtt-8"> </span><span
|
|---|
| 10245 | class="cmtt-8"> </span><span
|
|---|
| 10246 | class="cmtt-8"> </span><span
|
|---|
| 10247 | class="cmtt-8"> </span><span
|
|---|
| 10248 | class="cmtt-8"> </span><span
|
|---|
| 10249 | class="cmtt-8"> </span><span
|
|---|
| 10250 | class="cmtt-8"> </span><span
|
|---|
| 10251 | class="cmtt-8"> </span><span
|
|---|
| 10252 | class="cmtt-8"> </span><span
|
|---|
| 10253 | class="cmtt-8"> </span><span
|
|---|
| 10254 | class="cmtt-8"> </span><span
|
|---|
| 10255 | class="cmtt-8"> </span><span
|
|---|
| 10256 | class="cmtt-8"> </span><span
|
|---|
| 10257 | class="cmtt-8"> 19)</span><span
|
|---|
| 10258 | class="cmtt-8"> decode</span><span
|
|---|
| 10259 | class="cmtt-8"> partition</span><span
|
|---|
| 10260 | class="cmtt-8"> into</span><span
|
|---|
| 10261 | class="cmtt-8"> output</span><span
|
|---|
| 10262 | class="cmtt-8"> vector</span><span
|
|---|
| 10263 | class="cmtt-8"> number</span><span
|
|---|
| 10264 | class="cmtt-8"> [j],</span><span
|
|---|
| 10265 | class="cmtt-8"> starting</span><span
|
|---|
| 10266 | class="cmtt-8"> at</span><span
|
|---|
| 10267 | class="cmtt-8"> scalar</span>
|
|---|
| 10268 | <br class="fancyvrb" /><a
|
|---|
| 10269 | id="x1-112100r42"></a><span
|
|---|
| 10270 | class="cmr-6">42</span><span
|
|---|
| 10271 | class="cmtt-8"> </span><span
|
|---|
| 10272 | class="cmtt-8"> </span><span
|
|---|
| 10273 | class="cmtt-8"> </span><span
|
|---|
| 10274 | class="cmtt-8"> </span><span
|
|---|
| 10275 | class="cmtt-8"> </span><span
|
|---|
| 10276 | class="cmtt-8"> </span><span
|
|---|
| 10277 | class="cmtt-8"> </span><span
|
|---|
| 10278 | class="cmtt-8"> </span><span
|
|---|
| 10279 | class="cmtt-8"> </span><span
|
|---|
| 10280 | class="cmtt-8"> </span><span
|
|---|
| 10281 | class="cmtt-8"> </span><span
|
|---|
| 10282 | class="cmtt-8"> </span><span
|
|---|
| 10283 | class="cmtt-8"> </span><span
|
|---|
| 10284 | class="cmtt-8"> </span><span
|
|---|
| 10285 | class="cmtt-8"> </span><span
|
|---|
| 10286 | class="cmtt-8"> </span><span
|
|---|
| 10287 | class="cmtt-8"> </span><span
|
|---|
| 10288 | class="cmtt-8"> </span><span
|
|---|
| 10289 | class="cmtt-8"> </span><span
|
|---|
| 10290 | class="cmtt-8"> </span><span
|
|---|
| 10291 | class="cmtt-8"> </span><span
|
|---|
| 10292 | class="cmtt-8"> </span><span
|
|---|
| 10293 | class="cmtt-8"> </span><span
|
|---|
| 10294 | class="cmtt-8"> </span><span
|
|---|
| 10295 | class="cmtt-8"> </span><span
|
|---|
| 10296 | class="cmtt-8"> </span><span
|
|---|
| 10297 | class="cmtt-8"> </span><span
|
|---|
| 10298 | class="cmtt-8"> </span><span
|
|---|
| 10299 | class="cmtt-8"> </span><span
|
|---|
| 10300 | class="cmtt-8"> </span><span
|
|---|
| 10301 | class="cmtt-8"> </span><span
|
|---|
| 10302 | class="cmtt-8"> </span><span
|
|---|
| 10303 | class="cmtt-8"> </span><span
|
|---|
| 10304 | class="cmtt-8"> </span><span
|
|---|
| 10305 | class="cmtt-8"> </span><span
|
|---|
| 10306 | class="cmtt-8"> offset</span><span
|
|---|
| 10307 | class="cmtt-8"> [limit\_residue\_begin]+[partition\_count]*[residue\_partition\_size]</span><span
|
|---|
| 10308 | class="cmtt-8"> using</span>
|
|---|
| 10309 | <br class="fancyvrb" /><a
|
|---|
| 10310 | id="x1-112102r43"></a><span
|
|---|
| 10311 | class="cmr-6">43</span><span
|
|---|
| 10312 | class="cmtt-8"> </span><span
|
|---|
| 10313 | class="cmtt-8"> </span><span
|
|---|
| 10314 | class="cmtt-8"> </span><span
|
|---|
| 10315 | class="cmtt-8"> </span><span
|
|---|
| 10316 | class="cmtt-8"> </span><span
|
|---|
| 10317 | class="cmtt-8"> </span><span
|
|---|
| 10318 | class="cmtt-8"> </span><span
|
|---|
| 10319 | class="cmtt-8"> </span><span
|
|---|
| 10320 | class="cmtt-8"> </span><span
|
|---|
| 10321 | class="cmtt-8"> </span><span
|
|---|
| 10322 | class="cmtt-8"> </span><span
|
|---|
| 10323 | class="cmtt-8"> </span><span
|
|---|
| 10324 | class="cmtt-8"> </span><span
|
|---|
| 10325 | class="cmtt-8"> </span><span
|
|---|
| 10326 | class="cmtt-8"> </span><span
|
|---|
| 10327 | class="cmtt-8"> </span><span
|
|---|
| 10328 | class="cmtt-8"> </span><span
|
|---|
| 10329 | class="cmtt-8"> </span><span
|
|---|
| 10330 | class="cmtt-8"> </span><span
|
|---|
| 10331 | class="cmtt-8"> </span><span
|
|---|
| 10332 | class="cmtt-8"> </span><span
|
|---|
| 10333 | class="cmtt-8"> </span><span
|
|---|
| 10334 | class="cmtt-8"> </span><span
|
|---|
| 10335 | class="cmtt-8"> </span><span
|
|---|
| 10336 | class="cmtt-8"> </span><span
|
|---|
| 10337 | class="cmtt-8"> </span><span
|
|---|
| 10338 | class="cmtt-8"> </span><span
|
|---|
| 10339 | class="cmtt-8"> </span><span
|
|---|
| 10340 | class="cmtt-8"> </span><span
|
|---|
| 10341 | class="cmtt-8"> </span><span
|
|---|
| 10342 | class="cmtt-8"> </span><span
|
|---|
| 10343 | class="cmtt-8"> </span><span
|
|---|
| 10344 | class="cmtt-8"> </span><span
|
|---|
| 10345 | class="cmtt-8"> </span><span
|
|---|
| 10346 | class="cmtt-8"> </span><span
|
|---|
| 10347 | class="cmtt-8"> codebook</span><span
|
|---|
| 10348 | class="cmtt-8"> number</span><span
|
|---|
| 10349 | class="cmtt-8"> [vqbook]</span><span
|
|---|
| 10350 | class="cmtt-8"> in</span><span
|
|---|
| 10351 | class="cmtt-8"> VQ</span><span
|
|---|
| 10352 | class="cmtt-8"> context</span><br class="fancyvrb" /><a
|
|---|
| 10353 | id="x1-112104r44"></a><span
|
|---|
| 10354 | class="cmr-6">44</span><span
|
|---|
| 10355 | class="cmtt-8"> </span><span
|
|---|
| 10356 | class="cmtt-8"> </span><span
|
|---|
| 10357 | class="cmtt-8"> </span><span
|
|---|
| 10358 | class="cmtt-8"> </span><span
|
|---|
| 10359 | class="cmtt-8"> </span><span
|
|---|
| 10360 | class="cmtt-8"> </span><span
|
|---|
| 10361 | class="cmtt-8"> </span><span
|
|---|
| 10362 | class="cmtt-8"> </span><span
|
|---|
| 10363 | class="cmtt-8"> </span><span
|
|---|
| 10364 | class="cmtt-8"> </span><span
|
|---|
| 10365 | class="cmtt-8"> </span><span
|
|---|
| 10366 | class="cmtt-8"> </span><span
|
|---|
| 10367 | class="cmtt-8"> </span><span
|
|---|
| 10368 | class="cmtt-8"> </span><span
|
|---|
| 10369 | class="cmtt-8"> </span><span
|
|---|
| 10370 | class="cmtt-8"> </span><span
|
|---|
| 10371 | class="cmtt-8"> </span><span
|
|---|
| 10372 | class="cmtt-8"> </span><span
|
|---|
| 10373 | class="cmtt-8"> </span><span
|
|---|
| 10374 | class="cmtt-8"> </span><span
|
|---|
| 10375 | class="cmtt-8"> </span><span
|
|---|
| 10376 | class="cmtt-8"> </span><span
|
|---|
| 10377 | class="cmtt-8"> </span><span
|
|---|
| 10378 | class="cmtt-8"> </span><span
|
|---|
| 10379 | class="cmtt-8"> </span><span
|
|---|
| 10380 | class="cmtt-8"> }</span>
|
|---|
| 10381 | <br class="fancyvrb" /><a
|
|---|
| 10382 | id="x1-112106r45"></a><span
|
|---|
| 10383 | class="cmr-6">45</span><span
|
|---|
| 10384 | class="cmtt-8"> </span><span
|
|---|
| 10385 | class="cmtt-8"> </span><span
|
|---|
| 10386 | class="cmtt-8"> </span><span
|
|---|
| 10387 | class="cmtt-8"> </span><span
|
|---|
| 10388 | class="cmtt-8"> </span><span
|
|---|
| 10389 | class="cmtt-8"> </span><span
|
|---|
| 10390 | class="cmtt-8"> </span><span
|
|---|
| 10391 | class="cmtt-8"> </span><span
|
|---|
| 10392 | class="cmtt-8"> </span><span
|
|---|
| 10393 | class="cmtt-8"> </span><span
|
|---|
| 10394 | class="cmtt-8"> </span><span
|
|---|
| 10395 | class="cmtt-8"> </span><span
|
|---|
| 10396 | class="cmtt-8"> </span><span
|
|---|
| 10397 | class="cmtt-8"> </span><span
|
|---|
| 10398 | class="cmtt-8"> </span><span
|
|---|
| 10399 | class="cmtt-8"> </span><span
|
|---|
| 10400 | class="cmtt-8"> </span><span
|
|---|
| 10401 | class="cmtt-8"> </span><span
|
|---|
| 10402 | class="cmtt-8"> </span><span
|
|---|
| 10403 | class="cmtt-8"> </span><span
|
|---|
| 10404 | class="cmtt-8"> }</span><br class="fancyvrb" /><a
|
|---|
| 10405 | id="x1-112108r46"></a><span
|
|---|
| 10406 | class="cmr-6">46</span><br class="fancyvrb" /><a
|
|---|
| 10407 | id="x1-112110r47"></a><span
|
|---|
| 10408 | class="cmr-6">47</span><span
|
|---|
| 10409 | class="cmtt-8"> </span><span
|
|---|
| 10410 | class="cmtt-8"> </span><span
|
|---|
| 10411 | class="cmtt-8"> </span><span
|
|---|
| 10412 | class="cmtt-8"> </span><span
|
|---|
| 10413 | class="cmtt-8"> </span><span
|
|---|
| 10414 | class="cmtt-8"> </span><span
|
|---|
| 10415 | class="cmtt-8"> </span><span
|
|---|
| 10416 | class="cmtt-8"> </span><span
|
|---|
| 10417 | class="cmtt-8"> </span><span
|
|---|
| 10418 | class="cmtt-8"> </span><span
|
|---|
| 10419 | class="cmtt-8"> </span><span
|
|---|
| 10420 | class="cmtt-8"> </span><span
|
|---|
| 10421 | class="cmtt-8"> </span><span
|
|---|
| 10422 | class="cmtt-8"> </span><span
|
|---|
| 10423 | class="cmtt-8"> </span><span
|
|---|
| 10424 | class="cmtt-8"> </span><span
|
|---|
| 10425 | class="cmtt-8"> 20)</span><span
|
|---|
| 10426 | class="cmtt-8"> increment</span><span
|
|---|
| 10427 | class="cmtt-8"> [partition\_count]</span><span
|
|---|
| 10428 | class="cmtt-8"> by</span><span
|
|---|
| 10429 | class="cmtt-8"> one</span><br class="fancyvrb" /><a
|
|---|
| 10430 | id="x1-112112r48"></a><span
|
|---|
| 10431 | class="cmr-6">48</span><br class="fancyvrb" /><a
|
|---|
| 10432 | id="x1-112114r49"></a><span
|
|---|
| 10433 | class="cmr-6">49</span><span
|
|---|
| 10434 | class="cmtt-8"> </span><span
|
|---|
| 10435 | class="cmtt-8"> </span><span
|
|---|
| 10436 | class="cmtt-8"> </span><span
|
|---|
| 10437 | class="cmtt-8"> </span><span
|
|---|
| 10438 | class="cmtt-8"> </span><span
|
|---|
| 10439 | class="cmtt-8"> </span><span
|
|---|
| 10440 | class="cmtt-8"> </span><span
|
|---|
| 10441 | class="cmtt-8"> </span><span
|
|---|
| 10442 | class="cmtt-8"> </span><span
|
|---|
| 10443 | class="cmtt-8"> </span><span
|
|---|
| 10444 | class="cmtt-8"> </span><span
|
|---|
| 10445 | class="cmtt-8"> </span><span
|
|---|
| 10446 | class="cmtt-8"> </span><span
|
|---|
| 10447 | class="cmtt-8"> </span><span
|
|---|
| 10448 | class="cmtt-8"> }</span><br class="fancyvrb" /><a
|
|---|
| 10449 | id="x1-112116r50"></a><span
|
|---|
| 10450 | class="cmr-6">50</span><span
|
|---|
| 10451 | class="cmtt-8"> </span><span
|
|---|
| 10452 | class="cmtt-8"> </span><span
|
|---|
| 10453 | class="cmtt-8"> </span><span
|
|---|
| 10454 | class="cmtt-8"> </span><span
|
|---|
| 10455 | class="cmtt-8"> </span><span
|
|---|
| 10456 | class="cmtt-8"> </span><span
|
|---|
| 10457 | class="cmtt-8"> </span><span
|
|---|
| 10458 | class="cmtt-8"> </span><span
|
|---|
| 10459 | class="cmtt-8"> </span><span
|
|---|
| 10460 | class="cmtt-8"> }</span><br class="fancyvrb" /><a
|
|---|
| 10461 | id="x1-112118r51"></a><span
|
|---|
| 10462 | class="cmr-6">51</span><span
|
|---|
| 10463 | class="cmtt-8"> </span><span
|
|---|
| 10464 | class="cmtt-8"> </span><span
|
|---|
| 10465 | class="cmtt-8"> </span><span
|
|---|
| 10466 | class="cmtt-8"> </span><span
|
|---|
| 10467 | class="cmtt-8"> }</span><br class="fancyvrb" /><a
|
|---|
| 10468 | id="x1-112120r52"></a><span
|
|---|
| 10469 | class="cmr-6">52</span><br class="fancyvrb" /><a
|
|---|
| 10470 | id="x1-112122r53"></a><span
|
|---|
| 10471 | class="cmr-6">53</span><span
|
|---|
| 10472 | class="cmtt-8"> 21)</span><span
|
|---|
| 10473 | class="cmtt-8"> done</span><br class="fancyvrb" /><a
|
|---|
| 10474 | id="x1-112124r54"></a><span
|
|---|
| 10475 | class="cmr-6">54</span></div>
|
|---|
| 10476 | <!--l. 343--><p class="noindent" >An end-of-packet condition during packet decode is to be considered a nominal occurrence.
|
|---|
| 10477 | Decode returns the result of vector decode up to that point.
|
|---|
| 10478 | <!--l. 349--><p class="noindent" >
|
|---|
| 10479 | <h5 class="subsubsectionHead"><span class="titlemark">8.6.3. </span> <a
|
|---|
| 10480 | id="x1-1130008.6.3"></a>format 0 specifics</h5>
|
|---|
| 10481 | <!--l. 351--><p class="noindent" >Format zero decodes partitions exactly as described earlier in the ’Residue Format: residue 0’
|
|---|
| 10482 | section. The following pseudocode presents the same algorithm. Assume:
|
|---|
| 10483 |
|
|---|
| 10484 |
|
|---|
| 10485 |
|
|---|
| 10486 | <ul class="itemize1">
|
|---|
| 10487 | <li class="itemize"><span
|
|---|
| 10488 | class="cmtt-12">[n] </span>is the value in <span
|
|---|
| 10489 | class="cmtt-12">[residue</span><span
|
|---|
| 10490 | class="cmtt-12">_partition</span><span
|
|---|
| 10491 | class="cmtt-12">_size]</span>
|
|---|
| 10492 | </li>
|
|---|
| 10493 | <li class="itemize"><span
|
|---|
| 10494 | class="cmtt-12">[v] </span>is the residue vector
|
|---|
| 10495 | </li>
|
|---|
| 10496 | <li class="itemize"><span
|
|---|
| 10497 | class="cmtt-12">[offset] </span>is the beginning read offset in [v]</li></ul>
|
|---|
| 10498 | <!--l. 362--><p class="noindent" >
|
|---|
| 10499 | <div class="fancyvrb" id="fancyvrb41"><a
|
|---|
| 10500 | id="x1-113002r1"></a><span
|
|---|
| 10501 | class="cmr-6">1</span><span
|
|---|
| 10502 | class="cmtt-8"> 1)</span><span
|
|---|
| 10503 | class="cmtt-8"> [step]</span><span
|
|---|
| 10504 | class="cmtt-8"> =</span><span
|
|---|
| 10505 | class="cmtt-8"> [n]</span><span
|
|---|
| 10506 | class="cmtt-8"> /</span><span
|
|---|
| 10507 | class="cmtt-8"> [codebook\_dimensions]</span><br class="fancyvrb" /><a
|
|---|
| 10508 | id="x1-113004r2"></a><span
|
|---|
| 10509 | class="cmr-6">2</span><span
|
|---|
| 10510 | class="cmtt-8"> 2)</span><span
|
|---|
| 10511 | class="cmtt-8"> iterate</span><span
|
|---|
| 10512 | class="cmtt-8"> [i]</span><span
|
|---|
| 10513 | class="cmtt-8"> over</span><span
|
|---|
| 10514 | class="cmtt-8"> the</span><span
|
|---|
| 10515 | class="cmtt-8"> range</span><span
|
|---|
| 10516 | class="cmtt-8"> 0</span><span
|
|---|
| 10517 | class="cmtt-8"> ...</span><span
|
|---|
| 10518 | class="cmtt-8"> [step]-1</span><span
|
|---|
| 10519 | class="cmtt-8"> {</span><br class="fancyvrb" /><a
|
|---|
| 10520 | id="x1-113006r3"></a><span
|
|---|
| 10521 | class="cmr-6">3</span>
|
|---|
| 10522 | <br class="fancyvrb" /><a
|
|---|
| 10523 | id="x1-113008r4"></a><span
|
|---|
| 10524 | class="cmr-6">4</span><span
|
|---|
| 10525 | class="cmtt-8"> </span><span
|
|---|
| 10526 | class="cmtt-8"> </span><span
|
|---|
| 10527 | class="cmtt-8"> </span><span
|
|---|
| 10528 | class="cmtt-8"> </span><span
|
|---|
| 10529 | class="cmtt-8"> </span><span
|
|---|
| 10530 | class="cmtt-8"> 3)</span><span
|
|---|
| 10531 | class="cmtt-8"> vector</span><span
|
|---|
| 10532 | class="cmtt-8"> [entry\_temp]</span><span
|
|---|
| 10533 | class="cmtt-8"> =</span><span
|
|---|
| 10534 | class="cmtt-8"> read</span><span
|
|---|
| 10535 | class="cmtt-8"> vector</span><span
|
|---|
| 10536 | class="cmtt-8"> from</span><span
|
|---|
| 10537 | class="cmtt-8"> packet</span><span
|
|---|
| 10538 | class="cmtt-8"> using</span><span
|
|---|
| 10539 | class="cmtt-8"> current</span><span
|
|---|
| 10540 | class="cmtt-8"> codebook</span><span
|
|---|
| 10541 | class="cmtt-8"> in</span><span
|
|---|
| 10542 | class="cmtt-8"> VQ</span><span
|
|---|
| 10543 | class="cmtt-8"> context</span>
|
|---|
| 10544 | <br class="fancyvrb" /><a
|
|---|
| 10545 | id="x1-113010r5"></a><span
|
|---|
| 10546 | class="cmr-6">5</span><span
|
|---|
| 10547 | class="cmtt-8"> </span><span
|
|---|
| 10548 | class="cmtt-8"> </span><span
|
|---|
| 10549 | class="cmtt-8"> </span><span
|
|---|
| 10550 | class="cmtt-8"> </span><span
|
|---|
| 10551 | class="cmtt-8"> </span><span
|
|---|
| 10552 | class="cmtt-8"> 4)</span><span
|
|---|
| 10553 | class="cmtt-8"> iterate</span><span
|
|---|
| 10554 | class="cmtt-8"> [j]</span><span
|
|---|
| 10555 | class="cmtt-8"> over</span><span
|
|---|
| 10556 | class="cmtt-8"> the</span><span
|
|---|
| 10557 | class="cmtt-8"> range</span><span
|
|---|
| 10558 | class="cmtt-8"> 0</span><span
|
|---|
| 10559 | class="cmtt-8"> ...</span><span
|
|---|
| 10560 | class="cmtt-8"> [codebook\_dimensions]-1</span><span
|
|---|
| 10561 | class="cmtt-8"> {</span><br class="fancyvrb" /><a
|
|---|
| 10562 | id="x1-113012r6"></a><span
|
|---|
| 10563 | class="cmr-6">6</span><br class="fancyvrb" /><a
|
|---|
| 10564 | id="x1-113014r7"></a><span
|
|---|
| 10565 | class="cmr-6">7</span><span
|
|---|
| 10566 | class="cmtt-8"> </span><span
|
|---|
| 10567 | class="cmtt-8"> </span><span
|
|---|
| 10568 | class="cmtt-8"> </span><span
|
|---|
| 10569 | class="cmtt-8"> </span><span
|
|---|
| 10570 | class="cmtt-8"> </span><span
|
|---|
| 10571 | class="cmtt-8"> </span><span
|
|---|
| 10572 | class="cmtt-8"> </span><span
|
|---|
| 10573 | class="cmtt-8"> </span><span
|
|---|
| 10574 | class="cmtt-8"> </span><span
|
|---|
| 10575 | class="cmtt-8"> </span><span
|
|---|
| 10576 | class="cmtt-8"> 5)</span><span
|
|---|
| 10577 | class="cmtt-8"> vector</span><span
|
|---|
| 10578 | class="cmtt-8"> [v]</span><span
|
|---|
| 10579 | class="cmtt-8"> element</span><span
|
|---|
| 10580 | class="cmtt-8"> ([offset]+[i]+[j]*[step])</span><span
|
|---|
| 10581 | class="cmtt-8"> =</span>
|
|---|
| 10582 | <br class="fancyvrb" /><a
|
|---|
| 10583 | id="x1-113016r8"></a><span
|
|---|
| 10584 | class="cmr-6">8</span> <span
|
|---|
| 10585 | class="cmtt-8"> </span><span
|
|---|
| 10586 | class="cmtt-8"> </span><span
|
|---|
| 10587 | class="cmtt-8"> </span><span
|
|---|
| 10588 | class="cmtt-8"> </span><span
|
|---|
| 10589 | class="cmtt-8"> </span><span
|
|---|
| 10590 | class="cmtt-8"> </span><span
|
|---|
| 10591 | class="cmtt-8"> </span><span
|
|---|
| 10592 | class="cmtt-8"> vector</span><span
|
|---|
| 10593 | class="cmtt-8"> [v]</span><span
|
|---|
| 10594 | class="cmtt-8"> element</span><span
|
|---|
| 10595 | class="cmtt-8"> ([offset]+[i]+[j]*[step])</span><span
|
|---|
| 10596 | class="cmtt-8"> +</span><br class="fancyvrb" /><a
|
|---|
| 10597 | id="x1-113018r9"></a><span
|
|---|
| 10598 | class="cmr-6">9</span><span
|
|---|
| 10599 | class="cmtt-8"> </span><span
|
|---|
| 10600 | class="cmtt-8"> </span><span
|
|---|
| 10601 | class="cmtt-8"> </span><span
|
|---|
| 10602 | class="cmtt-8"> </span><span
|
|---|
| 10603 | class="cmtt-8"> </span><span
|
|---|
| 10604 | class="cmtt-8"> </span><span
|
|---|
| 10605 | class="cmtt-8"> </span><span
|
|---|
| 10606 | class="cmtt-8"> </span><span
|
|---|
| 10607 | class="cmtt-8"> </span><span
|
|---|
| 10608 | class="cmtt-8"> </span><span
|
|---|
| 10609 | class="cmtt-8"> </span><span
|
|---|
| 10610 | class="cmtt-8"> </span><span
|
|---|
| 10611 | class="cmtt-8"> </span><span
|
|---|
| 10612 | class="cmtt-8"> </span><span
|
|---|
| 10613 | class="cmtt-8"> </span><span
|
|---|
| 10614 | class="cmtt-8"> vector</span><span
|
|---|
| 10615 | class="cmtt-8"> [entry\_temp]</span><span
|
|---|
| 10616 | class="cmtt-8"> element</span><span
|
|---|
| 10617 | class="cmtt-8"> [j]</span><br class="fancyvrb" /><a
|
|---|
| 10618 | id="x1-113020r10"></a><span
|
|---|
| 10619 | class="cmr-6">10</span><br class="fancyvrb" /><a
|
|---|
| 10620 | id="x1-113022r11"></a><span
|
|---|
| 10621 | class="cmr-6">11</span><span
|
|---|
| 10622 | class="cmtt-8"> </span><span
|
|---|
| 10623 | class="cmtt-8"> </span><span
|
|---|
| 10624 | class="cmtt-8"> </span><span
|
|---|
| 10625 | class="cmtt-8"> </span><span
|
|---|
| 10626 | class="cmtt-8"> </span><span
|
|---|
| 10627 | class="cmtt-8"> </span><span
|
|---|
| 10628 | class="cmtt-8"> </span><span
|
|---|
| 10629 | class="cmtt-8"> </span><span
|
|---|
| 10630 | class="cmtt-8"> }</span><br class="fancyvrb" /><a
|
|---|
| 10631 | id="x1-113024r12"></a><span
|
|---|
| 10632 | class="cmr-6">12</span><br class="fancyvrb" /><a
|
|---|
| 10633 | id="x1-113026r13"></a><span
|
|---|
| 10634 | class="cmr-6">13</span><span
|
|---|
| 10635 | class="cmtt-8"> </span><span
|
|---|
| 10636 | class="cmtt-8"> </span><span
|
|---|
| 10637 | class="cmtt-8"> </span><span
|
|---|
| 10638 | class="cmtt-8"> }</span><br class="fancyvrb" /><a
|
|---|
| 10639 | id="x1-113028r14"></a><span
|
|---|
| 10640 | class="cmr-6">14</span><br class="fancyvrb" /><a
|
|---|
| 10641 | id="x1-113030r15"></a><span
|
|---|
| 10642 | class="cmr-6">15</span><span
|
|---|
| 10643 | class="cmtt-8"> </span><span
|
|---|
| 10644 | class="cmtt-8"> 6)</span><span
|
|---|
| 10645 | class="cmtt-8"> done</span><br class="fancyvrb" /><a
|
|---|
| 10646 | id="x1-113032r16"></a><span
|
|---|
| 10647 | class="cmr-6">16</span></div>
|
|---|
| 10648 | <!--l. 383--><p class="noindent" >
|
|---|
| 10649 | <h5 class="subsubsectionHead"><span class="titlemark">8.6.4. </span> <a
|
|---|
| 10650 | id="x1-1140008.6.4"></a>format 1 specifics</h5>
|
|---|
| 10651 | <!--l. 385--><p class="noindent" >Format 1 decodes partitions exactly as described earlier in the ’Residue Format: residue 1’
|
|---|
| 10652 | section. The following pseudocode presents the same algorithm. Assume:
|
|---|
| 10653 | <ul class="itemize1">
|
|---|
| 10654 | <li class="itemize"><span
|
|---|
| 10655 | class="cmtt-12">[n] </span>is the value in <span
|
|---|
| 10656 | class="cmtt-12">[residue</span><span
|
|---|
| 10657 | class="cmtt-12">_partition</span><span
|
|---|
| 10658 | class="cmtt-12">_size]</span>
|
|---|
| 10659 | </li>
|
|---|
| 10660 | <li class="itemize"><span
|
|---|
| 10661 | class="cmtt-12">[v] </span>is the residue vector
|
|---|
| 10662 | </li>
|
|---|
| 10663 | <li class="itemize"><span
|
|---|
| 10664 | class="cmtt-12">[offset] </span>is the beginning read offset in [v]</li></ul>
|
|---|
| 10665 | <!--l. 397--><p class="noindent" >
|
|---|
| 10666 | <div class="fancyvrb" id="fancyvrb42"><a
|
|---|
| 10667 | id="x1-114002r1"></a><span
|
|---|
| 10668 | class="cmr-6">1</span><span
|
|---|
| 10669 | class="cmtt-8"> 1)</span><span
|
|---|
| 10670 | class="cmtt-8"> [i]</span><span
|
|---|
| 10671 | class="cmtt-8"> =</span><span
|
|---|
| 10672 | class="cmtt-8"> 0</span><br class="fancyvrb" /><a
|
|---|
| 10673 | id="x1-114004r2"></a><span
|
|---|
| 10674 | class="cmr-6">2</span><span
|
|---|
| 10675 | class="cmtt-8"> 2)</span><span
|
|---|
| 10676 | class="cmtt-8"> vector</span><span
|
|---|
| 10677 | class="cmtt-8"> [entry\_temp]</span><span
|
|---|
| 10678 | class="cmtt-8"> =</span><span
|
|---|
| 10679 | class="cmtt-8"> read</span><span
|
|---|
| 10680 | class="cmtt-8"> vector</span><span
|
|---|
| 10681 | class="cmtt-8"> from</span><span
|
|---|
| 10682 | class="cmtt-8"> packet</span><span
|
|---|
| 10683 | class="cmtt-8"> using</span><span
|
|---|
| 10684 | class="cmtt-8"> current</span><span
|
|---|
| 10685 | class="cmtt-8"> codebook</span><span
|
|---|
| 10686 | class="cmtt-8"> in</span><span
|
|---|
| 10687 | class="cmtt-8"> VQ</span><span
|
|---|
| 10688 | class="cmtt-8"> context</span>
|
|---|
| 10689 | <br class="fancyvrb" /><a
|
|---|
| 10690 | id="x1-114006r3"></a><span
|
|---|
| 10691 | class="cmr-6">3</span><span
|
|---|
| 10692 | class="cmtt-8"> 3)</span><span
|
|---|
| 10693 | class="cmtt-8"> iterate</span><span
|
|---|
| 10694 | class="cmtt-8"> [j]</span><span
|
|---|
| 10695 | class="cmtt-8"> over</span><span
|
|---|
| 10696 | class="cmtt-8"> the</span><span
|
|---|
| 10697 | class="cmtt-8"> range</span><span
|
|---|
| 10698 | class="cmtt-8"> 0</span><span
|
|---|
| 10699 | class="cmtt-8"> ...</span><span
|
|---|
| 10700 | class="cmtt-8"> [codebook\_dimensions]-1</span><span
|
|---|
| 10701 | class="cmtt-8"> {</span><br class="fancyvrb" /><a
|
|---|
| 10702 | id="x1-114008r4"></a><span
|
|---|
| 10703 | class="cmr-6">4</span><br class="fancyvrb" /><a
|
|---|
| 10704 | id="x1-114010r5"></a><span
|
|---|
| 10705 | class="cmr-6">5</span><span
|
|---|
| 10706 | class="cmtt-8"> </span><span
|
|---|
| 10707 | class="cmtt-8"> </span><span
|
|---|
| 10708 | class="cmtt-8"> </span><span
|
|---|
| 10709 | class="cmtt-8"> </span><span
|
|---|
| 10710 | class="cmtt-8"> </span><span
|
|---|
| 10711 | class="cmtt-8"> 4)</span><span
|
|---|
| 10712 | class="cmtt-8"> vector</span><span
|
|---|
| 10713 | class="cmtt-8"> [v]</span><span
|
|---|
| 10714 | class="cmtt-8"> element</span><span
|
|---|
| 10715 | class="cmtt-8"> ([offset]+[i])</span><span
|
|---|
| 10716 | class="cmtt-8"> =</span><br class="fancyvrb" /><a
|
|---|
| 10717 | id="x1-114012r6"></a><span
|
|---|
| 10718 | class="cmr-6">6</span> <span
|
|---|
| 10719 | class="cmtt-8"> </span><span
|
|---|
| 10720 | class="cmtt-8"> vector</span><span
|
|---|
| 10721 | class="cmtt-8"> [v]</span><span
|
|---|
| 10722 | class="cmtt-8"> element</span><span
|
|---|
| 10723 | class="cmtt-8"> ([offset]+[i])</span><span
|
|---|
| 10724 | class="cmtt-8"> +</span>
|
|---|
| 10725 | <br class="fancyvrb" /><a
|
|---|
| 10726 | id="x1-114014r7"></a><span
|
|---|
| 10727 | class="cmr-6">7</span><span
|
|---|
| 10728 | class="cmtt-8"> </span><span
|
|---|
| 10729 | class="cmtt-8"> </span><span
|
|---|
| 10730 | class="cmtt-8"> </span><span
|
|---|
| 10731 | class="cmtt-8"> </span><span
|
|---|
| 10732 | class="cmtt-8"> </span><span
|
|---|
| 10733 | class="cmtt-8"> </span><span
|
|---|
| 10734 | class="cmtt-8"> </span><span
|
|---|
| 10735 | class="cmtt-8"> </span><span
|
|---|
| 10736 | class="cmtt-8"> </span><span
|
|---|
| 10737 | class="cmtt-8"> vector</span><span
|
|---|
| 10738 | class="cmtt-8"> [entry\_temp]</span><span
|
|---|
| 10739 | class="cmtt-8"> element</span><span
|
|---|
| 10740 | class="cmtt-8"> [j]</span><br class="fancyvrb" /><a
|
|---|
| 10741 | id="x1-114016r8"></a><span
|
|---|
| 10742 | class="cmr-6">8</span><span
|
|---|
| 10743 | class="cmtt-8"> </span><span
|
|---|
| 10744 | class="cmtt-8"> </span><span
|
|---|
| 10745 | class="cmtt-8"> </span><span
|
|---|
| 10746 | class="cmtt-8"> </span><span
|
|---|
| 10747 | class="cmtt-8"> </span><span
|
|---|
| 10748 | class="cmtt-8"> 5)</span><span
|
|---|
| 10749 | class="cmtt-8"> increment</span><span
|
|---|
| 10750 | class="cmtt-8"> [i]</span><br class="fancyvrb" /><a
|
|---|
| 10751 | id="x1-114018r9"></a><span
|
|---|
| 10752 | class="cmr-6">9</span><br class="fancyvrb" /><a
|
|---|
| 10753 | id="x1-114020r10"></a><span
|
|---|
| 10754 | class="cmr-6">10</span><span
|
|---|
| 10755 | class="cmtt-8"> </span><span
|
|---|
| 10756 | class="cmtt-8"> </span><span
|
|---|
| 10757 | class="cmtt-8"> </span><span
|
|---|
| 10758 | class="cmtt-8"> }</span><br class="fancyvrb" /><a
|
|---|
| 10759 | id="x1-114022r11"></a><span
|
|---|
| 10760 | class="cmr-6">11</span><br class="fancyvrb" /><a
|
|---|
| 10761 | id="x1-114024r12"></a><span
|
|---|
| 10762 | class="cmr-6">12</span><span
|
|---|
| 10763 | class="cmtt-8"> </span><span
|
|---|
| 10764 | class="cmtt-8"> 6)</span><span
|
|---|
| 10765 | class="cmtt-8"> if</span><span
|
|---|
| 10766 | class="cmtt-8"> (</span><span
|
|---|
| 10767 | class="cmtt-8"> [i]</span><span
|
|---|
| 10768 | class="cmtt-8"> is</span><span
|
|---|
| 10769 | class="cmtt-8"> less</span><span
|
|---|
| 10770 | class="cmtt-8"> than</span><span
|
|---|
| 10771 | class="cmtt-8"> [n]</span><span
|
|---|
| 10772 | class="cmtt-8"> )</span><span
|
|---|
| 10773 | class="cmtt-8"> continue</span><span
|
|---|
| 10774 | class="cmtt-8"> at</span><span
|
|---|
| 10775 | class="cmtt-8"> step</span><span
|
|---|
| 10776 | class="cmtt-8"> 2</span><br class="fancyvrb" /><a
|
|---|
| 10777 | id="x1-114026r13"></a><span
|
|---|
| 10778 | class="cmr-6">13</span><span
|
|---|
| 10779 | class="cmtt-8"> </span><span
|
|---|
| 10780 | class="cmtt-8"> 7)</span><span
|
|---|
| 10781 | class="cmtt-8"> done</span></div>
|
|---|
| 10782 | <!--l. 415--><p class="noindent" >
|
|---|
| 10783 | <h5 class="subsubsectionHead"><span class="titlemark">8.6.5. </span> <a
|
|---|
| 10784 | id="x1-1150008.6.5"></a>format 2 specifics</h5>
|
|---|
| 10785 |
|
|---|
| 10786 |
|
|---|
| 10787 |
|
|---|
| 10788 | <!--l. 417--><p class="noindent" >Format 2 is reducible to format 1. It may be implemented as an additional step prior to and an
|
|---|
| 10789 | additional post-decode step after a normal format 1 decode.
|
|---|
| 10790 | <!--l. 420--><p class="noindent" >Format 2 handles ’do not decode’ vectors differently than residue 0 or 1; if all vectors are marked
|
|---|
| 10791 | ’do not decode’, no decode occurrs. However, if at least one vector is to be decoded, all
|
|---|
| 10792 | the vectors are decoded. We then request normal format 1 to decode a single vector
|
|---|
| 10793 | representing all output channels, rather than a vector for each channel. After decode,
|
|---|
| 10794 | deinterleave the vector into independent vectors, one for each output channel. That
|
|---|
| 10795 | is:
|
|---|
| 10796 | <!--l. 428--><p class="noindent" >
|
|---|
| 10797 | <dl class="enumerate-enumitem"><dt class="enumerate-enumitem">
|
|---|
| 10798 | 1. </dt><dd
|
|---|
| 10799 | class="enumerate-enumitem">If all vectors 0 through <span
|
|---|
| 10800 | class="cmti-12">ch</span>-1 are marked ’do not decode’, allocate and clear a single
|
|---|
| 10801 | vector <span
|
|---|
| 10802 | class="cmtt-12">[v]</span>of length <span
|
|---|
| 10803 | class="cmti-12">ch*n </span>and skip step 2 below; proceed directly to the post-decode
|
|---|
| 10804 | step.
|
|---|
| 10805 | </dd><dt class="enumerate-enumitem">
|
|---|
| 10806 | 2. </dt><dd
|
|---|
| 10807 | class="enumerate-enumitem">Rather than performing format 1 decode to produce <span
|
|---|
| 10808 | class="cmti-12">ch </span>vectors of length <span
|
|---|
| 10809 | class="cmti-12">n </span>each, call
|
|---|
| 10810 | format 1 decode to produce a single vector <span
|
|---|
| 10811 | class="cmtt-12">[v] </span>of length <span
|
|---|
| 10812 | class="cmti-12">ch*n</span>.
|
|---|
| 10813 | </dd><dt class="enumerate-enumitem">
|
|---|
| 10814 | 3. </dt><dd
|
|---|
| 10815 | class="enumerate-enumitem">Post decode: Deinterleave the single vector <span
|
|---|
| 10816 | class="cmtt-12">[v] </span>returned by format 1 decode as
|
|---|
| 10817 | described above into <span
|
|---|
| 10818 | class="cmti-12">ch </span>independent vectors, one for each outputchannel, according
|
|---|
| 10819 | to:
|
|---|
| 10820 | <div class="fancyvrb" id="fancyvrb43"><a
|
|---|
| 10821 | id="x1-115005r1"></a><span
|
|---|
| 10822 | class="cmr-6">1</span><span
|
|---|
| 10823 | class="cmtt-8"> </span><span
|
|---|
| 10824 | class="cmtt-8"> 1)</span><span
|
|---|
| 10825 | class="cmtt-8"> iterate</span><span
|
|---|
| 10826 | class="cmtt-8"> [i]</span><span
|
|---|
| 10827 | class="cmtt-8"> over</span><span
|
|---|
| 10828 | class="cmtt-8"> the</span><span
|
|---|
| 10829 | class="cmtt-8"> range</span><span
|
|---|
| 10830 | class="cmtt-8"> 0</span><span
|
|---|
| 10831 | class="cmtt-8"> ...</span><span
|
|---|
| 10832 | class="cmtt-8"> [n]-1</span><span
|
|---|
| 10833 | class="cmtt-8"> {</span><br class="fancyvrb" /><a
|
|---|
| 10834 | id="x1-115007r2"></a><span
|
|---|
| 10835 | class="cmr-6">2</span><br class="fancyvrb" /><a
|
|---|
| 10836 | id="x1-115009r3"></a><span
|
|---|
| 10837 | class="cmr-6">3</span><span
|
|---|
| 10838 | class="cmtt-8"> </span><span
|
|---|
| 10839 | class="cmtt-8"> </span><span
|
|---|
| 10840 | class="cmtt-8"> </span><span
|
|---|
| 10841 | class="cmtt-8"> </span><span
|
|---|
| 10842 | class="cmtt-8"> </span><span
|
|---|
| 10843 | class="cmtt-8"> </span><span
|
|---|
| 10844 | class="cmtt-8"> 2)</span><span
|
|---|
| 10845 | class="cmtt-8"> iterate</span><span
|
|---|
| 10846 | class="cmtt-8"> [j]</span><span
|
|---|
| 10847 | class="cmtt-8"> over</span><span
|
|---|
| 10848 | class="cmtt-8"> the</span><span
|
|---|
| 10849 | class="cmtt-8"> range</span><span
|
|---|
| 10850 | class="cmtt-8"> 0</span><span
|
|---|
| 10851 | class="cmtt-8"> ...</span><span
|
|---|
| 10852 | class="cmtt-8"> [ch]-1</span><span
|
|---|
| 10853 | class="cmtt-8"> {</span><br class="fancyvrb" /><a
|
|---|
| 10854 | id="x1-115011r4"></a><span
|
|---|
| 10855 | class="cmr-6">4</span>
|
|---|
| 10856 | <br class="fancyvrb" /><a
|
|---|
| 10857 | id="x1-115013r5"></a><span
|
|---|
| 10858 | class="cmr-6">5</span><span
|
|---|
| 10859 | class="cmtt-8"> </span><span
|
|---|
| 10860 | class="cmtt-8"> </span><span
|
|---|
| 10861 | class="cmtt-8"> </span><span
|
|---|
| 10862 | class="cmtt-8"> </span><span
|
|---|
| 10863 | class="cmtt-8"> </span><span
|
|---|
| 10864 | class="cmtt-8"> </span><span
|
|---|
| 10865 | class="cmtt-8"> </span><span
|
|---|
| 10866 | class="cmtt-8"> </span><span
|
|---|
| 10867 | class="cmtt-8"> </span><span
|
|---|
| 10868 | class="cmtt-8"> </span><span
|
|---|
| 10869 | class="cmtt-8"> </span><span
|
|---|
| 10870 | class="cmtt-8"> 3)</span><span
|
|---|
| 10871 | class="cmtt-8"> output</span><span
|
|---|
| 10872 | class="cmtt-8"> vector</span><span
|
|---|
| 10873 | class="cmtt-8"> number</span><span
|
|---|
| 10874 | class="cmtt-8"> [j]</span><span
|
|---|
| 10875 | class="cmtt-8"> element</span><span
|
|---|
| 10876 | class="cmtt-8"> [i]</span><span
|
|---|
| 10877 | class="cmtt-8"> =</span><span
|
|---|
| 10878 | class="cmtt-8"> vector</span><span
|
|---|
| 10879 | class="cmtt-8"> [v]</span><span
|
|---|
| 10880 | class="cmtt-8"> element</span><span
|
|---|
| 10881 | class="cmtt-8"> ([i]</span><span
|
|---|
| 10882 | class="cmtt-8"> *</span><span
|
|---|
| 10883 | class="cmtt-8"> [ch]</span><span
|
|---|
| 10884 | class="cmtt-8"> +</span><span
|
|---|
| 10885 | class="cmtt-8"> [j])</span><br class="fancyvrb" /><a
|
|---|
| 10886 | id="x1-115015r6"></a><span
|
|---|
| 10887 | class="cmr-6">6</span><br class="fancyvrb" /><a
|
|---|
| 10888 | id="x1-115017r7"></a><span
|
|---|
| 10889 | class="cmr-6">7</span><span
|
|---|
| 10890 | class="cmtt-8"> </span><span
|
|---|
| 10891 | class="cmtt-8"> </span><span
|
|---|
| 10892 | class="cmtt-8"> </span><span
|
|---|
| 10893 | class="cmtt-8"> </span><span
|
|---|
| 10894 | class="cmtt-8"> </span><span
|
|---|
| 10895 | class="cmtt-8"> </span><span
|
|---|
| 10896 | class="cmtt-8"> </span><span
|
|---|
| 10897 | class="cmtt-8"> </span><span
|
|---|
| 10898 | class="cmtt-8"> </span><span
|
|---|
| 10899 | class="cmtt-8"> }</span><br class="fancyvrb" /><a
|
|---|
| 10900 | id="x1-115019r8"></a><span
|
|---|
| 10901 | class="cmr-6">8</span><span
|
|---|
| 10902 | class="cmtt-8"> </span><span
|
|---|
| 10903 | class="cmtt-8"> </span><span
|
|---|
| 10904 | class="cmtt-8"> </span><span
|
|---|
| 10905 | class="cmtt-8"> </span><span
|
|---|
| 10906 | class="cmtt-8"> }</span><br class="fancyvrb" /><a
|
|---|
| 10907 | id="x1-115021r9"></a><span
|
|---|
| 10908 | class="cmr-6">9</span><br class="fancyvrb" /><a
|
|---|
| 10909 | id="x1-115023r10"></a><span
|
|---|
| 10910 | class="cmr-6">10</span><span
|
|---|
| 10911 | class="cmtt-8"> </span><span
|
|---|
| 10912 | class="cmtt-8"> 4)</span><span
|
|---|
| 10913 | class="cmtt-8"> done</span></div>
|
|---|
| 10914 | </dd></dl>
|
|---|
| 10915 |
|
|---|
| 10916 |
|
|---|
| 10917 |
|
|---|
| 10918 |
|
|---|
| 10919 |
|
|---|
| 10920 |
|
|---|
| 10921 | <h3 class="sectionHead"><span class="titlemark">9. </span> <a
|
|---|
| 10922 | id="x1-1160009"></a>Helper equations</h3>
|
|---|
| 10923 | <!--l. 5--><p class="noindent" >
|
|---|
| 10924 | <h4 class="subsectionHead"><span class="titlemark">9.1. </span> <a
|
|---|
| 10925 | id="x1-1170009.1"></a>Overview</h4>
|
|---|
| 10926 | <!--l. 7--><p class="noindent" >The equations below are used in multiple places by the Vorbis codec specification. Rather than
|
|---|
| 10927 | cluttering up the main specification documents, they are defined here and referenced where
|
|---|
| 10928 | appropriate.
|
|---|
| 10929 | <!--l. 12--><p class="noindent" >
|
|---|
| 10930 | <h4 class="subsectionHead"><span class="titlemark">9.2. </span> <a
|
|---|
| 10931 | id="x1-1180009.2"></a>Functions</h4>
|
|---|
| 10932 | <!--l. 14--><p class="noindent" >
|
|---|
| 10933 | <h5 class="subsubsectionHead"><span class="titlemark">9.2.1. </span> <a
|
|---|
| 10934 | id="x1-1190009.2.1"></a>ilog</h5>
|
|---|
| 10935 | <!--l. 16--><p class="noindent" >The ”ilog(x)” function returns the position number (1 through n) of the highest set bit in the
|
|---|
| 10936 | two’s complement integer value <span
|
|---|
| 10937 | class="cmtt-12">[x]</span>. Values of <span
|
|---|
| 10938 | class="cmtt-12">[x] </span>less than zero are defined to return
|
|---|
| 10939 | zero.
|
|---|
| 10940 | <!--l. 19--><p class="noindent" >
|
|---|
| 10941 | <div class="fancyvrb" id="fancyvrb44"><a
|
|---|
| 10942 | id="x1-119002r1"></a><span
|
|---|
| 10943 | class="cmr-6">1</span><span
|
|---|
| 10944 | class="cmtt-8"> </span><span
|
|---|
| 10945 | class="cmtt-8"> 1)</span><span
|
|---|
| 10946 | class="cmtt-8"> [return\_value]</span><span
|
|---|
| 10947 | class="cmtt-8"> =</span><span
|
|---|
| 10948 | class="cmtt-8"> 0;</span><br class="fancyvrb" /><a
|
|---|
| 10949 | id="x1-119004r2"></a><span
|
|---|
| 10950 | class="cmr-6">2</span><span
|
|---|
| 10951 | class="cmtt-8"> </span><span
|
|---|
| 10952 | class="cmtt-8"> 2)</span><span
|
|---|
| 10953 | class="cmtt-8"> if</span><span
|
|---|
| 10954 | class="cmtt-8"> (</span><span
|
|---|
| 10955 | class="cmtt-8"> [x]</span><span
|
|---|
| 10956 | class="cmtt-8"> is</span><span
|
|---|
| 10957 | class="cmtt-8"> greater</span><span
|
|---|
| 10958 | class="cmtt-8"> than</span><span
|
|---|
| 10959 | class="cmtt-8"> zero</span><span
|
|---|
| 10960 | class="cmtt-8"> )</span><span
|
|---|
| 10961 | class="cmtt-8"> {</span><br class="fancyvrb" /><a
|
|---|
| 10962 | id="x1-119006r3"></a><span
|
|---|
| 10963 | class="cmr-6">3</span><br class="fancyvrb" /><a
|
|---|
| 10964 | id="x1-119008r4"></a><span
|
|---|
| 10965 | class="cmr-6">4</span><span
|
|---|
| 10966 | class="cmtt-8"> </span><span
|
|---|
| 10967 | class="cmtt-8"> </span><span
|
|---|
| 10968 | class="cmtt-8"> </span><span
|
|---|
| 10969 | class="cmtt-8"> </span><span
|
|---|
| 10970 | class="cmtt-8"> </span><span
|
|---|
| 10971 | class="cmtt-8"> </span><span
|
|---|
| 10972 | class="cmtt-8"> 3)</span><span
|
|---|
| 10973 | class="cmtt-8"> increment</span><span
|
|---|
| 10974 | class="cmtt-8"> [return\_value];</span>
|
|---|
| 10975 | <br class="fancyvrb" /><a
|
|---|
| 10976 | id="x1-119010r5"></a><span
|
|---|
| 10977 | class="cmr-6">5</span><span
|
|---|
| 10978 | class="cmtt-8"> </span><span
|
|---|
| 10979 | class="cmtt-8"> </span><span
|
|---|
| 10980 | class="cmtt-8"> </span><span
|
|---|
| 10981 | class="cmtt-8"> </span><span
|
|---|
| 10982 | class="cmtt-8"> </span><span
|
|---|
| 10983 | class="cmtt-8"> </span><span
|
|---|
| 10984 | class="cmtt-8"> 4)</span><span
|
|---|
| 10985 | class="cmtt-8"> logical</span><span
|
|---|
| 10986 | class="cmtt-8"> shift</span><span
|
|---|
| 10987 | class="cmtt-8"> [x]</span><span
|
|---|
| 10988 | class="cmtt-8"> one</span><span
|
|---|
| 10989 | class="cmtt-8"> bit</span><span
|
|---|
| 10990 | class="cmtt-8"> to</span><span
|
|---|
| 10991 | class="cmtt-8"> the</span><span
|
|---|
| 10992 | class="cmtt-8"> right,</span><span
|
|---|
| 10993 | class="cmtt-8"> padding</span><span
|
|---|
| 10994 | class="cmtt-8"> the</span><span
|
|---|
| 10995 | class="cmtt-8"> MSb</span><span
|
|---|
| 10996 | class="cmtt-8"> with</span><span
|
|---|
| 10997 | class="cmtt-8"> zero</span><br class="fancyvrb" /><a
|
|---|
| 10998 | id="x1-119012r6"></a><span
|
|---|
| 10999 | class="cmr-6">6</span><span
|
|---|
| 11000 | class="cmtt-8"> </span><span
|
|---|
| 11001 | class="cmtt-8"> </span><span
|
|---|
| 11002 | class="cmtt-8"> </span><span
|
|---|
| 11003 | class="cmtt-8"> </span><span
|
|---|
| 11004 | class="cmtt-8"> </span><span
|
|---|
| 11005 | class="cmtt-8"> </span><span
|
|---|
| 11006 | class="cmtt-8"> 5)</span><span
|
|---|
| 11007 | class="cmtt-8"> repeat</span><span
|
|---|
| 11008 | class="cmtt-8"> at</span><span
|
|---|
| 11009 | class="cmtt-8"> step</span><span
|
|---|
| 11010 | class="cmtt-8"> 2)</span><br class="fancyvrb" /><a
|
|---|
| 11011 | id="x1-119014r7"></a><span
|
|---|
| 11012 | class="cmr-6">7</span><br class="fancyvrb" /><a
|
|---|
| 11013 | id="x1-119016r8"></a><span
|
|---|
| 11014 | class="cmr-6">8</span><span
|
|---|
| 11015 | class="cmtt-8"> </span><span
|
|---|
| 11016 | class="cmtt-8"> </span><span
|
|---|
| 11017 | class="cmtt-8"> </span><span
|
|---|
| 11018 | class="cmtt-8"> </span><span
|
|---|
| 11019 | class="cmtt-8"> }</span><br class="fancyvrb" /><a
|
|---|
| 11020 | id="x1-119018r9"></a><span
|
|---|
| 11021 | class="cmr-6">9</span><br class="fancyvrb" /><a
|
|---|
| 11022 | id="x1-119020r10"></a><span
|
|---|
| 11023 | class="cmr-6">10</span><span
|
|---|
| 11024 | class="cmtt-8"> </span><span
|
|---|
| 11025 | class="cmtt-8"> </span><span
|
|---|
| 11026 | class="cmtt-8"> 6)</span><span
|
|---|
| 11027 | class="cmtt-8"> done</span></div>
|
|---|
| 11028 | <!--l. 32--><p class="noindent" >Examples:
|
|---|
| 11029 | <ul class="itemize1">
|
|---|
| 11030 | <li class="itemize">ilog(0) = 0;
|
|---|
| 11031 | </li>
|
|---|
| 11032 | <li class="itemize">ilog(1) = 1;
|
|---|
| 11033 |
|
|---|
| 11034 |
|
|---|
| 11035 |
|
|---|
| 11036 | </li>
|
|---|
| 11037 | <li class="itemize">ilog(2) = 2;
|
|---|
| 11038 | </li>
|
|---|
| 11039 | <li class="itemize">ilog(3) = 2;
|
|---|
| 11040 | </li>
|
|---|
| 11041 | <li class="itemize">ilog(4) = 3;
|
|---|
| 11042 | </li>
|
|---|
| 11043 | <li class="itemize">ilog(7) = 3;
|
|---|
| 11044 | </li>
|
|---|
| 11045 | <li class="itemize">ilog(negative number) = 0;</li></ul>
|
|---|
| 11046 | <!--l. 47--><p class="noindent" >
|
|---|
| 11047 | <h5 class="subsubsectionHead"><span class="titlemark">9.2.2. </span> <a
|
|---|
| 11048 | id="x1-1200009.2.2"></a>float32_unpack</h5>
|
|---|
| 11049 | <!--l. 49--><p class="noindent" >”float32_unpack(x)” is intended to translate the packed binary representation of a Vorbis
|
|---|
| 11050 | codebook float value into the representation used by the decoder for floating point numbers. For
|
|---|
| 11051 | purposes of this example, we will unpack a Vorbis float32 into a host-native floating point
|
|---|
| 11052 | number.
|
|---|
| 11053 | <!--l. 55--><p class="noindent" >
|
|---|
| 11054 | <div class="fancyvrb" id="fancyvrb45"><a
|
|---|
| 11055 | id="x1-120002r1"></a><span
|
|---|
| 11056 | class="cmr-6">1</span><span
|
|---|
| 11057 | class="cmtt-8"> </span><span
|
|---|
| 11058 | class="cmtt-8"> 1)</span><span
|
|---|
| 11059 | class="cmtt-8"> [mantissa]</span><span
|
|---|
| 11060 | class="cmtt-8"> =</span><span
|
|---|
| 11061 | class="cmtt-8"> [x]</span><span
|
|---|
| 11062 | class="cmtt-8"> bitwise</span><span
|
|---|
| 11063 | class="cmtt-8"> AND</span><span
|
|---|
| 11064 | class="cmtt-8"> 0x1fffff</span><span
|
|---|
| 11065 | class="cmtt-8"> (unsigned</span><span
|
|---|
| 11066 | class="cmtt-8"> result)</span><br class="fancyvrb" /><a
|
|---|
| 11067 | id="x1-120004r2"></a><span
|
|---|
| 11068 | class="cmr-6">2</span><span
|
|---|
| 11069 | class="cmtt-8"> </span><span
|
|---|
| 11070 | class="cmtt-8"> 2)</span><span
|
|---|
| 11071 | class="cmtt-8"> [sign]</span><span
|
|---|
| 11072 | class="cmtt-8"> =</span><span
|
|---|
| 11073 | class="cmtt-8"> [x]</span><span
|
|---|
| 11074 | class="cmtt-8"> bitwise</span><span
|
|---|
| 11075 | class="cmtt-8"> AND</span><span
|
|---|
| 11076 | class="cmtt-8"> 0x80000000</span><span
|
|---|
| 11077 | class="cmtt-8"> (unsigned</span><span
|
|---|
| 11078 | class="cmtt-8"> result)</span>
|
|---|
| 11079 | <br class="fancyvrb" /><a
|
|---|
| 11080 | id="x1-120006r3"></a><span
|
|---|
| 11081 | class="cmr-6">3</span><span
|
|---|
| 11082 | class="cmtt-8"> </span><span
|
|---|
| 11083 | class="cmtt-8"> 3)</span><span
|
|---|
| 11084 | class="cmtt-8"> [exponent]</span><span
|
|---|
| 11085 | class="cmtt-8"> =</span><span
|
|---|
| 11086 | class="cmtt-8"> (</span><span
|
|---|
| 11087 | class="cmtt-8"> [x]</span><span
|
|---|
| 11088 | class="cmtt-8"> bitwise</span><span
|
|---|
| 11089 | class="cmtt-8"> AND</span><span
|
|---|
| 11090 | class="cmtt-8"> 0x7fe00000)</span><span
|
|---|
| 11091 | class="cmtt-8"> shifted</span><span
|
|---|
| 11092 | class="cmtt-8"> right</span><span
|
|---|
| 11093 | class="cmtt-8"> 21</span><span
|
|---|
| 11094 | class="cmtt-8"> bits</span><span
|
|---|
| 11095 | class="cmtt-8"> (unsigned</span><span
|
|---|
| 11096 | class="cmtt-8"> result)</span>
|
|---|
| 11097 | <br class="fancyvrb" /><a
|
|---|
| 11098 | id="x1-120008r4"></a><span
|
|---|
| 11099 | class="cmr-6">4</span><span
|
|---|
| 11100 | class="cmtt-8"> </span><span
|
|---|
| 11101 | class="cmtt-8"> 4)</span><span
|
|---|
| 11102 | class="cmtt-8"> if</span><span
|
|---|
| 11103 | class="cmtt-8"> (</span><span
|
|---|
| 11104 | class="cmtt-8"> [sign]</span><span
|
|---|
| 11105 | class="cmtt-8"> is</span><span
|
|---|
| 11106 | class="cmtt-8"> nonzero</span><span
|
|---|
| 11107 | class="cmtt-8"> )</span><span
|
|---|
| 11108 | class="cmtt-8"> then</span><span
|
|---|
| 11109 | class="cmtt-8"> negate</span><span
|
|---|
| 11110 | class="cmtt-8"> [mantissa]</span><br class="fancyvrb" /><a
|
|---|
| 11111 | id="x1-120010r5"></a><span
|
|---|
| 11112 | class="cmr-6">5</span><span
|
|---|
| 11113 | class="cmtt-8"> </span><span
|
|---|
| 11114 | class="cmtt-8"> 5)</span><span
|
|---|
| 11115 | class="cmtt-8"> return</span><span
|
|---|
| 11116 | class="cmtt-8"> [mantissa]</span><span
|
|---|
| 11117 | class="cmtt-8"> *</span><span
|
|---|
| 11118 | class="cmtt-8"> (</span><span
|
|---|
| 11119 | class="cmtt-8"> 2</span><span
|
|---|
| 11120 | class="cmtt-8"> ^</span><span
|
|---|
| 11121 | class="cmtt-8"> (</span><span
|
|---|
| 11122 | class="cmtt-8"> [exponent]</span><span
|
|---|
| 11123 | class="cmtt-8"> -</span><span
|
|---|
| 11124 | class="cmtt-8"> 788</span><span
|
|---|
| 11125 | class="cmtt-8"> )</span><span
|
|---|
| 11126 | class="cmtt-8"> )</span></div>
|
|---|
| 11127 | <!--l. 65--><p class="noindent" >
|
|---|
| 11128 | <h5 class="subsubsectionHead"><span class="titlemark">9.2.3. </span> <a
|
|---|
| 11129 | id="x1-1210009.2.3"></a>lookup1_values</h5>
|
|---|
| 11130 | <!--l. 67--><p class="noindent" >”lookup1_values(codebook_entries,codebook_dimensions)” is used to compute the
|
|---|
| 11131 | correct length of the value index for a codebook VQ lookup table of lookup type 1.
|
|---|
| 11132 | The values on this list are permuted to construct the VQ vector lookup table of size
|
|---|
| 11133 | <span
|
|---|
| 11134 | class="cmtt-12">[codebook</span><span
|
|---|
| 11135 | class="cmtt-12">_entries]</span>.
|
|---|
| 11136 | <!--l. 73--><p class="noindent" >The return value for this function is defined to be ’the greatest integer value for which
|
|---|
| 11137 | <span
|
|---|
| 11138 | class="cmtt-12">[return</span><span
|
|---|
| 11139 | class="cmtt-12">_value] </span>to the power of <span
|
|---|
| 11140 | class="cmtt-12">[codebook</span><span
|
|---|
| 11141 | class="cmtt-12">_dimensions] </span>is less than or equal to
|
|---|
| 11142 | <span
|
|---|
| 11143 | class="cmtt-12">[codebook</span><span
|
|---|
| 11144 | class="cmtt-12">_entries]</span>’.
|
|---|
| 11145 |
|
|---|
| 11146 |
|
|---|
| 11147 |
|
|---|
| 11148 | <!--l. 80--><p class="noindent" >
|
|---|
| 11149 | <h5 class="subsubsectionHead"><span class="titlemark">9.2.4. </span> <a
|
|---|
| 11150 | id="x1-1220009.2.4"></a>low_neighbor</h5>
|
|---|
| 11151 | <!--l. 82--><p class="noindent" >”low_neighbor(v,x)” finds the position <span
|
|---|
| 11152 | class="cmtt-12">n </span>in vector <span
|
|---|
| 11153 | class="cmtt-12">[v] </span>of the greatest value scalar element for
|
|---|
| 11154 | which <span
|
|---|
| 11155 | class="cmtt-12">n </span>is less than <span
|
|---|
| 11156 | class="cmtt-12">[x] </span>and vector <span
|
|---|
| 11157 | class="cmtt-12">[v] </span>element <span
|
|---|
| 11158 | class="cmtt-12">n </span>is less than vector <span
|
|---|
| 11159 | class="cmtt-12">[v] </span>element
|
|---|
| 11160 | <span
|
|---|
| 11161 | class="cmtt-12">[x]</span>.
|
|---|
| 11162 | <!--l. 87--><p class="noindent" >
|
|---|
| 11163 | <h5 class="subsubsectionHead"><span class="titlemark">9.2.5. </span> <a
|
|---|
| 11164 | id="x1-1230009.2.5"></a>high_neighbor</h5>
|
|---|
| 11165 | <!--l. 89--><p class="noindent" >”high_neighbor(v,x)” finds the position <span
|
|---|
| 11166 | class="cmtt-12">n </span>in vector [v] of the lowest value scalar element for
|
|---|
| 11167 | which <span
|
|---|
| 11168 | class="cmtt-12">n </span>is less than <span
|
|---|
| 11169 | class="cmtt-12">[x] </span>and vector <span
|
|---|
| 11170 | class="cmtt-12">[v] </span>element <span
|
|---|
| 11171 | class="cmtt-12">n </span>is greater than vector <span
|
|---|
| 11172 | class="cmtt-12">[v] </span>element
|
|---|
| 11173 | <span
|
|---|
| 11174 | class="cmtt-12">[x]</span>.
|
|---|
| 11175 | <!--l. 96--><p class="noindent" >
|
|---|
| 11176 | <h5 class="subsubsectionHead"><span class="titlemark">9.2.6. </span> <a
|
|---|
| 11177 | id="x1-1240009.2.6"></a>render_point</h5>
|
|---|
| 11178 | <!--l. 98--><p class="noindent" >”render_point(x0,y0,x1,y1,X)” is used to find the Y value at point X along the line specified by
|
|---|
| 11179 | x0, x1, y0 and y1. This function uses an integer algorithm to solve for the point directly without
|
|---|
| 11180 | calculating intervening values along the line.
|
|---|
| 11181 | <!--l. 103--><p class="noindent" >
|
|---|
| 11182 | <div class="fancyvrb" id="fancyvrb46"><a
|
|---|
| 11183 | id="x1-124002r1"></a><span
|
|---|
| 11184 | class="cmr-6">1</span><span
|
|---|
| 11185 | class="cmtt-8"> </span><span
|
|---|
| 11186 | class="cmtt-8"> 1)</span><span
|
|---|
| 11187 | class="cmtt-8"> </span><span
|
|---|
| 11188 | class="cmtt-8"> [dy]</span><span
|
|---|
| 11189 | class="cmtt-8"> =</span><span
|
|---|
| 11190 | class="cmtt-8"> [y1]</span><span
|
|---|
| 11191 | class="cmtt-8"> -</span><span
|
|---|
| 11192 | class="cmtt-8"> [y0]</span><br class="fancyvrb" /><a
|
|---|
| 11193 | id="x1-124004r2"></a><span
|
|---|
| 11194 | class="cmr-6">2</span><span
|
|---|
| 11195 | class="cmtt-8"> </span><span
|
|---|
| 11196 | class="cmtt-8"> 2)</span><span
|
|---|
| 11197 | class="cmtt-8"> [adx]</span><span
|
|---|
| 11198 | class="cmtt-8"> =</span><span
|
|---|
| 11199 | class="cmtt-8"> [x1]</span><span
|
|---|
| 11200 | class="cmtt-8"> -</span><span
|
|---|
| 11201 | class="cmtt-8"> [x0]</span><br class="fancyvrb" /><a
|
|---|
| 11202 | id="x1-124006r3"></a><span
|
|---|
| 11203 | class="cmr-6">3</span><span
|
|---|
| 11204 | class="cmtt-8"> </span><span
|
|---|
| 11205 | class="cmtt-8"> 3)</span><span
|
|---|
| 11206 | class="cmtt-8"> [ady]</span><span
|
|---|
| 11207 | class="cmtt-8"> =</span><span
|
|---|
| 11208 | class="cmtt-8"> absolute</span><span
|
|---|
| 11209 | class="cmtt-8"> value</span><span
|
|---|
| 11210 | class="cmtt-8"> of</span><span
|
|---|
| 11211 | class="cmtt-8"> [dy]</span><br class="fancyvrb" /><a
|
|---|
| 11212 | id="x1-124008r4"></a><span
|
|---|
| 11213 | class="cmr-6">4</span><span
|
|---|
| 11214 | class="cmtt-8"> </span><span
|
|---|
| 11215 | class="cmtt-8"> 4)</span><span
|
|---|
| 11216 | class="cmtt-8"> [err]</span><span
|
|---|
| 11217 | class="cmtt-8"> =</span><span
|
|---|
| 11218 | class="cmtt-8"> [ady]</span><span
|
|---|
| 11219 | class="cmtt-8"> *</span><span
|
|---|
| 11220 | class="cmtt-8"> ([X]</span><span
|
|---|
| 11221 | class="cmtt-8"> -</span><span
|
|---|
| 11222 | class="cmtt-8"> [x0])</span>
|
|---|
| 11223 | <br class="fancyvrb" /><a
|
|---|
| 11224 | id="x1-124010r5"></a><span
|
|---|
| 11225 | class="cmr-6">5</span><span
|
|---|
| 11226 | class="cmtt-8"> </span><span
|
|---|
| 11227 | class="cmtt-8"> 5)</span><span
|
|---|
| 11228 | class="cmtt-8"> [off]</span><span
|
|---|
| 11229 | class="cmtt-8"> =</span><span
|
|---|
| 11230 | class="cmtt-8"> [err]</span><span
|
|---|
| 11231 | class="cmtt-8"> /</span><span
|
|---|
| 11232 | class="cmtt-8"> [adx]</span><span
|
|---|
| 11233 | class="cmtt-8"> using</span><span
|
|---|
| 11234 | class="cmtt-8"> integer</span><span
|
|---|
| 11235 | class="cmtt-8"> division</span><br class="fancyvrb" /><a
|
|---|
| 11236 | id="x1-124012r6"></a><span
|
|---|
| 11237 | class="cmr-6">6</span><span
|
|---|
| 11238 | class="cmtt-8"> </span><span
|
|---|
| 11239 | class="cmtt-8"> 6)</span><span
|
|---|
| 11240 | class="cmtt-8"> if</span><span
|
|---|
| 11241 | class="cmtt-8"> (</span><span
|
|---|
| 11242 | class="cmtt-8"> [dy]</span><span
|
|---|
| 11243 | class="cmtt-8"> is</span><span
|
|---|
| 11244 | class="cmtt-8"> less</span><span
|
|---|
| 11245 | class="cmtt-8"> than</span><span
|
|---|
| 11246 | class="cmtt-8"> zero</span><span
|
|---|
| 11247 | class="cmtt-8"> )</span><span
|
|---|
| 11248 | class="cmtt-8"> {</span><br class="fancyvrb" /><a
|
|---|
| 11249 | id="x1-124014r7"></a><span
|
|---|
| 11250 | class="cmr-6">7</span><br class="fancyvrb" /><a
|
|---|
| 11251 | id="x1-124016r8"></a><span
|
|---|
| 11252 | class="cmr-6">8</span><span
|
|---|
| 11253 | class="cmtt-8"> </span><span
|
|---|
| 11254 | class="cmtt-8"> </span><span
|
|---|
| 11255 | class="cmtt-8"> </span><span
|
|---|
| 11256 | class="cmtt-8"> </span><span
|
|---|
| 11257 | class="cmtt-8"> </span><span
|
|---|
| 11258 | class="cmtt-8"> </span><span
|
|---|
| 11259 | class="cmtt-8"> 7)</span><span
|
|---|
| 11260 | class="cmtt-8"> [Y]</span><span
|
|---|
| 11261 | class="cmtt-8"> =</span><span
|
|---|
| 11262 | class="cmtt-8"> [y0]</span><span
|
|---|
| 11263 | class="cmtt-8"> -</span><span
|
|---|
| 11264 | class="cmtt-8"> [off]</span><br class="fancyvrb" /><a
|
|---|
| 11265 | id="x1-124018r9"></a><span
|
|---|
| 11266 | class="cmr-6">9</span>
|
|---|
| 11267 | <br class="fancyvrb" /><a
|
|---|
| 11268 | id="x1-124020r10"></a><span
|
|---|
| 11269 | class="cmr-6">10</span><span
|
|---|
| 11270 | class="cmtt-8"> </span><span
|
|---|
| 11271 | class="cmtt-8"> </span><span
|
|---|
| 11272 | class="cmtt-8"> </span><span
|
|---|
| 11273 | class="cmtt-8"> </span><span
|
|---|
| 11274 | class="cmtt-8"> }</span><span
|
|---|
| 11275 | class="cmtt-8"> else</span><span
|
|---|
| 11276 | class="cmtt-8"> {</span><br class="fancyvrb" /><a
|
|---|
| 11277 | id="x1-124022r11"></a><span
|
|---|
| 11278 | class="cmr-6">11</span><br class="fancyvrb" /><a
|
|---|
| 11279 | id="x1-124024r12"></a><span
|
|---|
| 11280 | class="cmr-6">12</span><span
|
|---|
| 11281 | class="cmtt-8"> </span><span
|
|---|
| 11282 | class="cmtt-8"> </span><span
|
|---|
| 11283 | class="cmtt-8"> </span><span
|
|---|
| 11284 | class="cmtt-8"> </span><span
|
|---|
| 11285 | class="cmtt-8"> </span><span
|
|---|
| 11286 | class="cmtt-8"> </span><span
|
|---|
| 11287 | class="cmtt-8"> 8)</span><span
|
|---|
| 11288 | class="cmtt-8"> [Y]</span><span
|
|---|
| 11289 | class="cmtt-8"> =</span><span
|
|---|
| 11290 | class="cmtt-8"> [y0]</span><span
|
|---|
| 11291 | class="cmtt-8"> +</span><span
|
|---|
| 11292 | class="cmtt-8"> [off]</span><br class="fancyvrb" /><a
|
|---|
| 11293 | id="x1-124026r13"></a><span
|
|---|
| 11294 | class="cmr-6">13</span><br class="fancyvrb" /><a
|
|---|
| 11295 | id="x1-124028r14"></a><span
|
|---|
| 11296 | class="cmr-6">14</span><span
|
|---|
| 11297 | class="cmtt-8"> </span><span
|
|---|
| 11298 | class="cmtt-8"> </span><span
|
|---|
| 11299 | class="cmtt-8"> </span><span
|
|---|
| 11300 | class="cmtt-8"> </span><span
|
|---|
| 11301 | class="cmtt-8"> }</span><br class="fancyvrb" /><a
|
|---|
| 11302 | id="x1-124030r15"></a><span
|
|---|
| 11303 | class="cmr-6">15</span><br class="fancyvrb" /><a
|
|---|
| 11304 | id="x1-124032r16"></a><span
|
|---|
| 11305 | class="cmr-6">16</span><span
|
|---|
| 11306 | class="cmtt-8"> </span><span
|
|---|
| 11307 | class="cmtt-8"> 9)</span><span
|
|---|
| 11308 | class="cmtt-8"> done</span></div>
|
|---|
| 11309 | <!--l. 124--><p class="noindent" >
|
|---|
| 11310 | <h5 class="subsubsectionHead"><span class="titlemark">9.2.7. </span> <a
|
|---|
| 11311 | id="x1-1250009.2.7"></a>render_line</h5>
|
|---|
| 11312 |
|
|---|
| 11313 |
|
|---|
| 11314 |
|
|---|
| 11315 | <!--l. 126--><p class="noindent" >Floor decode type one uses the integer line drawing algorithm of ”render_line(x0, y0, x1, y1, v)”
|
|---|
| 11316 | to construct an integer floor curve for contiguous piecewise line segments. Note that it has not
|
|---|
| 11317 | been relevant elsewhere, but here we must define integer division as rounding division of both
|
|---|
| 11318 | positive and negative numbers toward zero.
|
|---|
| 11319 | <!--l. 133--><p class="noindent" >
|
|---|
| 11320 | <div class="fancyvrb" id="fancyvrb47"><a
|
|---|
| 11321 | id="x1-125002r1"></a><span
|
|---|
| 11322 | class="cmr-6">1</span><span
|
|---|
| 11323 | class="cmtt-8"> </span><span
|
|---|
| 11324 | class="cmtt-8"> 1)</span><span
|
|---|
| 11325 | class="cmtt-8"> </span><span
|
|---|
| 11326 | class="cmtt-8"> </span><span
|
|---|
| 11327 | class="cmtt-8"> [dy]</span><span
|
|---|
| 11328 | class="cmtt-8"> =</span><span
|
|---|
| 11329 | class="cmtt-8"> [y1]</span><span
|
|---|
| 11330 | class="cmtt-8"> -</span><span
|
|---|
| 11331 | class="cmtt-8"> [y0]</span><br class="fancyvrb" /><a
|
|---|
| 11332 | id="x1-125004r2"></a><span
|
|---|
| 11333 | class="cmr-6">2</span><span
|
|---|
| 11334 | class="cmtt-8"> </span><span
|
|---|
| 11335 | class="cmtt-8"> 2)</span><span
|
|---|
| 11336 | class="cmtt-8"> </span><span
|
|---|
| 11337 | class="cmtt-8"> [adx]</span><span
|
|---|
| 11338 | class="cmtt-8"> =</span><span
|
|---|
| 11339 | class="cmtt-8"> [x1]</span><span
|
|---|
| 11340 | class="cmtt-8"> -</span><span
|
|---|
| 11341 | class="cmtt-8"> [x0]</span><br class="fancyvrb" /><a
|
|---|
| 11342 | id="x1-125006r3"></a><span
|
|---|
| 11343 | class="cmr-6">3</span><span
|
|---|
| 11344 | class="cmtt-8"> </span><span
|
|---|
| 11345 | class="cmtt-8"> 3)</span><span
|
|---|
| 11346 | class="cmtt-8"> </span><span
|
|---|
| 11347 | class="cmtt-8"> [ady]</span><span
|
|---|
| 11348 | class="cmtt-8"> =</span><span
|
|---|
| 11349 | class="cmtt-8"> absolute</span><span
|
|---|
| 11350 | class="cmtt-8"> value</span><span
|
|---|
| 11351 | class="cmtt-8"> of</span><span
|
|---|
| 11352 | class="cmtt-8"> [dy]</span><br class="fancyvrb" /><a
|
|---|
| 11353 | id="x1-125008r4"></a><span
|
|---|
| 11354 | class="cmr-6">4</span><span
|
|---|
| 11355 | class="cmtt-8"> </span><span
|
|---|
| 11356 | class="cmtt-8"> 4)</span><span
|
|---|
| 11357 | class="cmtt-8"> [base]</span><span
|
|---|
| 11358 | class="cmtt-8"> =</span><span
|
|---|
| 11359 | class="cmtt-8"> [dy]</span><span
|
|---|
| 11360 | class="cmtt-8"> /</span><span
|
|---|
| 11361 | class="cmtt-8"> [adx]</span><span
|
|---|
| 11362 | class="cmtt-8"> using</span><span
|
|---|
| 11363 | class="cmtt-8"> integer</span><span
|
|---|
| 11364 | class="cmtt-8"> division</span>
|
|---|
| 11365 | <br class="fancyvrb" /><a
|
|---|
| 11366 | id="x1-125010r5"></a><span
|
|---|
| 11367 | class="cmr-6">5</span><span
|
|---|
| 11368 | class="cmtt-8"> </span><span
|
|---|
| 11369 | class="cmtt-8"> 5)</span><span
|
|---|
| 11370 | class="cmtt-8"> </span><span
|
|---|
| 11371 | class="cmtt-8"> </span><span
|
|---|
| 11372 | class="cmtt-8"> </span><span
|
|---|
| 11373 | class="cmtt-8"> [x]</span><span
|
|---|
| 11374 | class="cmtt-8"> =</span><span
|
|---|
| 11375 | class="cmtt-8"> [x0]</span><br class="fancyvrb" /><a
|
|---|
| 11376 | id="x1-125012r6"></a><span
|
|---|
| 11377 | class="cmr-6">6</span><span
|
|---|
| 11378 | class="cmtt-8"> </span><span
|
|---|
| 11379 | class="cmtt-8"> 6)</span><span
|
|---|
| 11380 | class="cmtt-8"> </span><span
|
|---|
| 11381 | class="cmtt-8"> </span><span
|
|---|
| 11382 | class="cmtt-8"> </span><span
|
|---|
| 11383 | class="cmtt-8"> [y]</span><span
|
|---|
| 11384 | class="cmtt-8"> =</span><span
|
|---|
| 11385 | class="cmtt-8"> [y0]</span><br class="fancyvrb" /><a
|
|---|
| 11386 | id="x1-125014r7"></a><span
|
|---|
| 11387 | class="cmr-6">7</span><span
|
|---|
| 11388 | class="cmtt-8"> </span><span
|
|---|
| 11389 | class="cmtt-8"> 7)</span><span
|
|---|
| 11390 | class="cmtt-8"> </span><span
|
|---|
| 11391 | class="cmtt-8"> [err]</span><span
|
|---|
| 11392 | class="cmtt-8"> =</span><span
|
|---|
| 11393 | class="cmtt-8"> 0</span><br class="fancyvrb" /><a
|
|---|
| 11394 | id="x1-125016r8"></a><span
|
|---|
| 11395 | class="cmr-6">8</span><br class="fancyvrb" /><a
|
|---|
| 11396 | id="x1-125018r9"></a><span
|
|---|
| 11397 | class="cmr-6">9</span><span
|
|---|
| 11398 | class="cmtt-8"> </span><span
|
|---|
| 11399 | class="cmtt-8"> 8)</span><span
|
|---|
| 11400 | class="cmtt-8"> if</span><span
|
|---|
| 11401 | class="cmtt-8"> (</span><span
|
|---|
| 11402 | class="cmtt-8"> [dy]</span><span
|
|---|
| 11403 | class="cmtt-8"> is</span><span
|
|---|
| 11404 | class="cmtt-8"> less</span><span
|
|---|
| 11405 | class="cmtt-8"> than</span><span
|
|---|
| 11406 | class="cmtt-8"> 0</span><span
|
|---|
| 11407 | class="cmtt-8"> )</span><span
|
|---|
| 11408 | class="cmtt-8"> {</span><br class="fancyvrb" /><a
|
|---|
| 11409 | id="x1-125020r10"></a><span
|
|---|
| 11410 | class="cmr-6">10</span><br class="fancyvrb" /><a
|
|---|
| 11411 | id="x1-125022r11"></a><span
|
|---|
| 11412 | class="cmr-6">11</span><span
|
|---|
| 11413 | class="cmtt-8"> </span><span
|
|---|
| 11414 | class="cmtt-8"> </span><span
|
|---|
| 11415 | class="cmtt-8"> </span><span
|
|---|
| 11416 | class="cmtt-8"> </span><span
|
|---|
| 11417 | class="cmtt-8"> </span><span
|
|---|
| 11418 | class="cmtt-8"> </span><span
|
|---|
| 11419 | class="cmtt-8"> </span><span
|
|---|
| 11420 | class="cmtt-8"> 9)</span><span
|
|---|
| 11421 | class="cmtt-8"> [sy]</span><span
|
|---|
| 11422 | class="cmtt-8"> =</span><span
|
|---|
| 11423 | class="cmtt-8"> [base]</span><span
|
|---|
| 11424 | class="cmtt-8"> -</span><span
|
|---|
| 11425 | class="cmtt-8"> 1</span><br class="fancyvrb" /><a
|
|---|
| 11426 | id="x1-125024r12"></a><span
|
|---|
| 11427 | class="cmr-6">12</span>
|
|---|
| 11428 | <br class="fancyvrb" /><a
|
|---|
| 11429 | id="x1-125026r13"></a><span
|
|---|
| 11430 | class="cmr-6">13</span><span
|
|---|
| 11431 | class="cmtt-8"> </span><span
|
|---|
| 11432 | class="cmtt-8"> </span><span
|
|---|
| 11433 | class="cmtt-8"> </span><span
|
|---|
| 11434 | class="cmtt-8"> </span><span
|
|---|
| 11435 | class="cmtt-8"> }</span><span
|
|---|
| 11436 | class="cmtt-8"> else</span><span
|
|---|
| 11437 | class="cmtt-8"> {</span><br class="fancyvrb" /><a
|
|---|
| 11438 | id="x1-125028r14"></a><span
|
|---|
| 11439 | class="cmr-6">14</span><br class="fancyvrb" /><a
|
|---|
| 11440 | id="x1-125030r15"></a><span
|
|---|
| 11441 | class="cmr-6">15</span><span
|
|---|
| 11442 | class="cmtt-8"> </span><span
|
|---|
| 11443 | class="cmtt-8"> </span><span
|
|---|
| 11444 | class="cmtt-8"> </span><span
|
|---|
| 11445 | class="cmtt-8"> </span><span
|
|---|
| 11446 | class="cmtt-8"> </span><span
|
|---|
| 11447 | class="cmtt-8"> </span><span
|
|---|
| 11448 | class="cmtt-8"> 10)</span><span
|
|---|
| 11449 | class="cmtt-8"> [sy]</span><span
|
|---|
| 11450 | class="cmtt-8"> =</span><span
|
|---|
| 11451 | class="cmtt-8"> [base]</span><span
|
|---|
| 11452 | class="cmtt-8"> +</span><span
|
|---|
| 11453 | class="cmtt-8"> 1</span><br class="fancyvrb" /><a
|
|---|
| 11454 | id="x1-125032r16"></a><span
|
|---|
| 11455 | class="cmr-6">16</span><br class="fancyvrb" /><a
|
|---|
| 11456 | id="x1-125034r17"></a><span
|
|---|
| 11457 | class="cmr-6">17</span><span
|
|---|
| 11458 | class="cmtt-8"> </span><span
|
|---|
| 11459 | class="cmtt-8"> </span><span
|
|---|
| 11460 | class="cmtt-8"> </span><span
|
|---|
| 11461 | class="cmtt-8"> </span><span
|
|---|
| 11462 | class="cmtt-8"> }</span><br class="fancyvrb" /><a
|
|---|
| 11463 | id="x1-125036r18"></a><span
|
|---|
| 11464 | class="cmr-6">18</span><br class="fancyvrb" /><a
|
|---|
| 11465 | id="x1-125038r19"></a><span
|
|---|
| 11466 | class="cmr-6">19</span><span
|
|---|
| 11467 | class="cmtt-8"> 11)</span><span
|
|---|
| 11468 | class="cmtt-8"> [ady]</span><span
|
|---|
| 11469 | class="cmtt-8"> =</span><span
|
|---|
| 11470 | class="cmtt-8"> [ady]</span><span
|
|---|
| 11471 | class="cmtt-8"> -</span><span
|
|---|
| 11472 | class="cmtt-8"> (absolute</span><span
|
|---|
| 11473 | class="cmtt-8"> value</span><span
|
|---|
| 11474 | class="cmtt-8"> of</span><span
|
|---|
| 11475 | class="cmtt-8"> [base])</span><span
|
|---|
| 11476 | class="cmtt-8"> *</span><span
|
|---|
| 11477 | class="cmtt-8"> [adx]</span>
|
|---|
| 11478 | <br class="fancyvrb" /><a
|
|---|
| 11479 | id="x1-125040r20"></a><span
|
|---|
| 11480 | class="cmr-6">20</span><span
|
|---|
| 11481 | class="cmtt-8"> 12)</span><span
|
|---|
| 11482 | class="cmtt-8"> vector</span><span
|
|---|
| 11483 | class="cmtt-8"> [v]</span><span
|
|---|
| 11484 | class="cmtt-8"> element</span><span
|
|---|
| 11485 | class="cmtt-8"> [x]</span><span
|
|---|
| 11486 | class="cmtt-8"> =</span><span
|
|---|
| 11487 | class="cmtt-8"> [y]</span><br class="fancyvrb" /><a
|
|---|
| 11488 | id="x1-125042r21"></a><span
|
|---|
| 11489 | class="cmr-6">21</span><br class="fancyvrb" /><a
|
|---|
| 11490 | id="x1-125044r22"></a><span
|
|---|
| 11491 | class="cmr-6">22</span><span
|
|---|
| 11492 | class="cmtt-8"> 13)</span><span
|
|---|
| 11493 | class="cmtt-8"> iterate</span><span
|
|---|
| 11494 | class="cmtt-8"> [x]</span><span
|
|---|
| 11495 | class="cmtt-8"> over</span><span
|
|---|
| 11496 | class="cmtt-8"> the</span><span
|
|---|
| 11497 | class="cmtt-8"> range</span><span
|
|---|
| 11498 | class="cmtt-8"> [x0]+1</span><span
|
|---|
| 11499 | class="cmtt-8"> ...</span><span
|
|---|
| 11500 | class="cmtt-8"> [x1]-1</span><span
|
|---|
| 11501 | class="cmtt-8"> {</span><br class="fancyvrb" /><a
|
|---|
| 11502 | id="x1-125046r23"></a><span
|
|---|
| 11503 | class="cmr-6">23</span><br class="fancyvrb" /><a
|
|---|
| 11504 | id="x1-125048r24"></a><span
|
|---|
| 11505 | class="cmr-6">24</span><span
|
|---|
| 11506 | class="cmtt-8"> </span><span
|
|---|
| 11507 | class="cmtt-8"> </span><span
|
|---|
| 11508 | class="cmtt-8"> </span><span
|
|---|
| 11509 | class="cmtt-8"> </span><span
|
|---|
| 11510 | class="cmtt-8"> </span><span
|
|---|
| 11511 | class="cmtt-8"> </span><span
|
|---|
| 11512 | class="cmtt-8"> 14)</span><span
|
|---|
| 11513 | class="cmtt-8"> [err]</span><span
|
|---|
| 11514 | class="cmtt-8"> =</span><span
|
|---|
| 11515 | class="cmtt-8"> [err]</span><span
|
|---|
| 11516 | class="cmtt-8"> +</span><span
|
|---|
| 11517 | class="cmtt-8"> [ady];</span>
|
|---|
| 11518 | <br class="fancyvrb" /><a
|
|---|
| 11519 | id="x1-125050r25"></a><span
|
|---|
| 11520 | class="cmr-6">25</span><span
|
|---|
| 11521 | class="cmtt-8"> </span><span
|
|---|
| 11522 | class="cmtt-8"> </span><span
|
|---|
| 11523 | class="cmtt-8"> </span><span
|
|---|
| 11524 | class="cmtt-8"> </span><span
|
|---|
| 11525 | class="cmtt-8"> </span><span
|
|---|
| 11526 | class="cmtt-8"> </span><span
|
|---|
| 11527 | class="cmtt-8"> 15)</span><span
|
|---|
| 11528 | class="cmtt-8"> if</span><span
|
|---|
| 11529 | class="cmtt-8"> (</span><span
|
|---|
| 11530 | class="cmtt-8"> [err]</span><span
|
|---|
| 11531 | class="cmtt-8"> >=</span><span
|
|---|
| 11532 | class="cmtt-8"> [adx]</span><span
|
|---|
| 11533 | class="cmtt-8"> )</span><span
|
|---|
| 11534 | class="cmtt-8"> {</span><br class="fancyvrb" /><a
|
|---|
| 11535 | id="x1-125052r26"></a><span
|
|---|
| 11536 | class="cmr-6">26</span><br class="fancyvrb" /><a
|
|---|
| 11537 | id="x1-125054r27"></a><span
|
|---|
| 11538 | class="cmr-6">27</span><span
|
|---|
| 11539 | class="cmtt-8"> </span><span
|
|---|
| 11540 | class="cmtt-8"> </span><span
|
|---|
| 11541 | class="cmtt-8"> </span><span
|
|---|
| 11542 | class="cmtt-8"> </span><span
|
|---|
| 11543 | class="cmtt-8"> </span><span
|
|---|
| 11544 | class="cmtt-8"> </span><span
|
|---|
| 11545 | class="cmtt-8"> </span><span
|
|---|
| 11546 | class="cmtt-8"> </span><span
|
|---|
| 11547 | class="cmtt-8"> </span><span
|
|---|
| 11548 | class="cmtt-8"> </span><span
|
|---|
| 11549 | class="cmtt-8"> </span><span
|
|---|
| 11550 | class="cmtt-8"> </span><span
|
|---|
| 11551 | class="cmtt-8"> 16)</span><span
|
|---|
| 11552 | class="cmtt-8"> [err]</span><span
|
|---|
| 11553 | class="cmtt-8"> =</span><span
|
|---|
| 11554 | class="cmtt-8"> [err]</span><span
|
|---|
| 11555 | class="cmtt-8"> -</span><span
|
|---|
| 11556 | class="cmtt-8"> [adx]</span><br class="fancyvrb" /><a
|
|---|
| 11557 | id="x1-125056r28"></a><span
|
|---|
| 11558 | class="cmr-6">28</span><span
|
|---|
| 11559 | class="cmtt-8"> </span><span
|
|---|
| 11560 | class="cmtt-8"> </span><span
|
|---|
| 11561 | class="cmtt-8"> </span><span
|
|---|
| 11562 | class="cmtt-8"> </span><span
|
|---|
| 11563 | class="cmtt-8"> </span><span
|
|---|
| 11564 | class="cmtt-8"> </span><span
|
|---|
| 11565 | class="cmtt-8"> </span><span
|
|---|
| 11566 | class="cmtt-8"> </span><span
|
|---|
| 11567 | class="cmtt-8"> </span><span
|
|---|
| 11568 | class="cmtt-8"> </span><span
|
|---|
| 11569 | class="cmtt-8"> </span><span
|
|---|
| 11570 | class="cmtt-8"> </span><span
|
|---|
| 11571 | class="cmtt-8"> 17)</span><span
|
|---|
| 11572 | class="cmtt-8"> </span><span
|
|---|
| 11573 | class="cmtt-8"> </span><span
|
|---|
| 11574 | class="cmtt-8"> [y]</span><span
|
|---|
| 11575 | class="cmtt-8"> =</span><span
|
|---|
| 11576 | class="cmtt-8"> [y]</span><span
|
|---|
| 11577 | class="cmtt-8"> +</span><span
|
|---|
| 11578 | class="cmtt-8"> [sy]</span><br class="fancyvrb" /><a
|
|---|
| 11579 | id="x1-125058r29"></a><span
|
|---|
| 11580 | class="cmr-6">29</span>
|
|---|
| 11581 | <br class="fancyvrb" /><a
|
|---|
| 11582 | id="x1-125060r30"></a><span
|
|---|
| 11583 | class="cmr-6">30</span><span
|
|---|
| 11584 | class="cmtt-8"> </span><span
|
|---|
| 11585 | class="cmtt-8"> </span><span
|
|---|
| 11586 | class="cmtt-8"> </span><span
|
|---|
| 11587 | class="cmtt-8"> </span><span
|
|---|
| 11588 | class="cmtt-8"> </span><span
|
|---|
| 11589 | class="cmtt-8"> </span><span
|
|---|
| 11590 | class="cmtt-8"> </span><span
|
|---|
| 11591 | class="cmtt-8"> </span><span
|
|---|
| 11592 | class="cmtt-8"> </span><span
|
|---|
| 11593 | class="cmtt-8"> </span><span
|
|---|
| 11594 | class="cmtt-8"> }</span><span
|
|---|
| 11595 | class="cmtt-8"> else</span><span
|
|---|
| 11596 | class="cmtt-8"> {</span><br class="fancyvrb" /><a
|
|---|
| 11597 | id="x1-125062r31"></a><span
|
|---|
| 11598 | class="cmr-6">31</span><br class="fancyvrb" /><a
|
|---|
| 11599 | id="x1-125064r32"></a><span
|
|---|
| 11600 | class="cmr-6">32</span><span
|
|---|
| 11601 | class="cmtt-8"> </span><span
|
|---|
| 11602 | class="cmtt-8"> </span><span
|
|---|
| 11603 | class="cmtt-8"> </span><span
|
|---|
| 11604 | class="cmtt-8"> </span><span
|
|---|
| 11605 | class="cmtt-8"> </span><span
|
|---|
| 11606 | class="cmtt-8"> </span><span
|
|---|
| 11607 | class="cmtt-8"> </span><span
|
|---|
| 11608 | class="cmtt-8"> </span><span
|
|---|
| 11609 | class="cmtt-8"> </span><span
|
|---|
| 11610 | class="cmtt-8"> </span><span
|
|---|
| 11611 | class="cmtt-8"> </span><span
|
|---|
| 11612 | class="cmtt-8"> </span><span
|
|---|
| 11613 | class="cmtt-8"> 18)</span><span
|
|---|
| 11614 | class="cmtt-8"> [y]</span><span
|
|---|
| 11615 | class="cmtt-8"> =</span><span
|
|---|
| 11616 | class="cmtt-8"> [y]</span><span
|
|---|
| 11617 | class="cmtt-8"> +</span><span
|
|---|
| 11618 | class="cmtt-8"> [base]</span><br class="fancyvrb" /><a
|
|---|
| 11619 | id="x1-125066r33"></a><span
|
|---|
| 11620 | class="cmr-6">33</span><br class="fancyvrb" /><a
|
|---|
| 11621 | id="x1-125068r34"></a><span
|
|---|
| 11622 | class="cmr-6">34</span><span
|
|---|
| 11623 | class="cmtt-8"> </span><span
|
|---|
| 11624 | class="cmtt-8"> </span><span
|
|---|
| 11625 | class="cmtt-8"> </span><span
|
|---|
| 11626 | class="cmtt-8"> </span><span
|
|---|
| 11627 | class="cmtt-8"> </span><span
|
|---|
| 11628 | class="cmtt-8"> </span><span
|
|---|
| 11629 | class="cmtt-8"> </span><span
|
|---|
| 11630 | class="cmtt-8"> </span><span
|
|---|
| 11631 | class="cmtt-8"> </span><span
|
|---|
| 11632 | class="cmtt-8"> </span><span
|
|---|
| 11633 | class="cmtt-8"> }</span><br class="fancyvrb" /><a
|
|---|
| 11634 | id="x1-125070r35"></a><span
|
|---|
| 11635 | class="cmr-6">35</span><br class="fancyvrb" /><a
|
|---|
| 11636 | id="x1-125072r36"></a><span
|
|---|
| 11637 | class="cmr-6">36</span><span
|
|---|
| 11638 | class="cmtt-8"> </span><span
|
|---|
| 11639 | class="cmtt-8"> </span><span
|
|---|
| 11640 | class="cmtt-8"> </span><span
|
|---|
| 11641 | class="cmtt-8"> </span><span
|
|---|
| 11642 | class="cmtt-8"> </span><span
|
|---|
| 11643 | class="cmtt-8"> </span><span
|
|---|
| 11644 | class="cmtt-8"> 19)</span><span
|
|---|
| 11645 | class="cmtt-8"> vector</span><span
|
|---|
| 11646 | class="cmtt-8"> [v]</span><span
|
|---|
| 11647 | class="cmtt-8"> element</span><span
|
|---|
| 11648 | class="cmtt-8"> [x]</span><span
|
|---|
| 11649 | class="cmtt-8"> =</span><span
|
|---|
| 11650 | class="cmtt-8"> [y]</span><br class="fancyvrb" /><a
|
|---|
| 11651 | id="x1-125074r37"></a><span
|
|---|
| 11652 | class="cmr-6">37</span><br class="fancyvrb" /><a
|
|---|
| 11653 | id="x1-125076r38"></a><span
|
|---|
| 11654 | class="cmr-6">38</span><span
|
|---|
| 11655 | class="cmtt-8"> </span><span
|
|---|
| 11656 | class="cmtt-8"> </span><span
|
|---|
| 11657 | class="cmtt-8"> </span><span
|
|---|
| 11658 | class="cmtt-8"> </span><span
|
|---|
| 11659 | class="cmtt-8"> }</span></div>
|
|---|
| 11660 |
|
|---|
| 11661 |
|
|---|
| 11662 |
|
|---|
| 11663 |
|
|---|
| 11664 |
|
|---|
| 11665 |
|
|---|
| 11666 | <h3 class="sectionHead"><span class="titlemark">10. </span> <a
|
|---|
| 11667 | id="x1-12600010"></a>Tables</h3>
|
|---|
| 11668 | <!--l. 5--><p class="noindent" >
|
|---|
| 11669 | <h4 class="subsectionHead"><span class="titlemark">10.1. </span> <a
|
|---|
| 11670 | id="x1-12700010.1"></a>floor1_inverse_dB_table</h4>
|
|---|
| 11671 | <!--l. 7--><p class="noindent" >The vector <span
|
|---|
| 11672 | class="cmtt-12">[floor1</span><span
|
|---|
| 11673 | class="cmtt-12">_inverse</span><span
|
|---|
| 11674 | class="cmtt-12">_dB</span><span
|
|---|
| 11675 | class="cmtt-12">_table] </span>is a 256 element static lookup table consisting of the
|
|---|
| 11676 | following values (read left to right then top to bottom):
|
|---|
| 11677 | <!--l. 11--><p class="noindent" >
|
|---|
| 11678 | <div class="fancyvrb" id="fancyvrb48"><a
|
|---|
| 11679 | id="x1-127002r1"></a><span
|
|---|
| 11680 | class="cmr-6">1</span><span
|
|---|
| 11681 | class="cmtt-8"> </span><span
|
|---|
| 11682 | class="cmtt-8"> 1.0649863e-07,</span><span
|
|---|
| 11683 | class="cmtt-8"> 1.1341951e-07,</span><span
|
|---|
| 11684 | class="cmtt-8"> 1.2079015e-07,</span><span
|
|---|
| 11685 | class="cmtt-8"> 1.2863978e-07,</span><br class="fancyvrb" /><a
|
|---|
| 11686 | id="x1-127004r2"></a><span
|
|---|
| 11687 | class="cmr-6">2</span><span
|
|---|
| 11688 | class="cmtt-8"> </span><span
|
|---|
| 11689 | class="cmtt-8"> 1.3699951e-07,</span><span
|
|---|
| 11690 | class="cmtt-8"> 1.4590251e-07,</span><span
|
|---|
| 11691 | class="cmtt-8"> 1.5538408e-07,</span><span
|
|---|
| 11692 | class="cmtt-8"> 1.6548181e-07,</span>
|
|---|
| 11693 | <br class="fancyvrb" /><a
|
|---|
| 11694 | id="x1-127006r3"></a><span
|
|---|
| 11695 | class="cmr-6">3</span><span
|
|---|
| 11696 | class="cmtt-8"> </span><span
|
|---|
| 11697 | class="cmtt-8"> 1.7623575e-07,</span><span
|
|---|
| 11698 | class="cmtt-8"> 1.8768855e-07,</span><span
|
|---|
| 11699 | class="cmtt-8"> 1.9988561e-07,</span><span
|
|---|
| 11700 | class="cmtt-8"> 2.1287530e-07,</span><br class="fancyvrb" /><a
|
|---|
| 11701 | id="x1-127008r4"></a><span
|
|---|
| 11702 | class="cmr-6">4</span><span
|
|---|
| 11703 | class="cmtt-8"> </span><span
|
|---|
| 11704 | class="cmtt-8"> 2.2670913e-07,</span><span
|
|---|
| 11705 | class="cmtt-8"> 2.4144197e-07,</span><span
|
|---|
| 11706 | class="cmtt-8"> 2.5713223e-07,</span><span
|
|---|
| 11707 | class="cmtt-8"> 2.7384213e-07,</span>
|
|---|
| 11708 | <br class="fancyvrb" /><a
|
|---|
| 11709 | id="x1-127010r5"></a><span
|
|---|
| 11710 | class="cmr-6">5</span><span
|
|---|
| 11711 | class="cmtt-8"> </span><span
|
|---|
| 11712 | class="cmtt-8"> 2.9163793e-07,</span><span
|
|---|
| 11713 | class="cmtt-8"> 3.1059021e-07,</span><span
|
|---|
| 11714 | class="cmtt-8"> 3.3077411e-07,</span><span
|
|---|
| 11715 | class="cmtt-8"> 3.5226968e-07,</span><br class="fancyvrb" /><a
|
|---|
| 11716 | id="x1-127012r6"></a><span
|
|---|
| 11717 | class="cmr-6">6</span><span
|
|---|
| 11718 | class="cmtt-8"> </span><span
|
|---|
| 11719 | class="cmtt-8"> 3.7516214e-07,</span><span
|
|---|
| 11720 | class="cmtt-8"> 3.9954229e-07,</span><span
|
|---|
| 11721 | class="cmtt-8"> 4.2550680e-07,</span><span
|
|---|
| 11722 | class="cmtt-8"> 4.5315863e-07,</span>
|
|---|
| 11723 | <br class="fancyvrb" /><a
|
|---|
| 11724 | id="x1-127014r7"></a><span
|
|---|
| 11725 | class="cmr-6">7</span><span
|
|---|
| 11726 | class="cmtt-8"> </span><span
|
|---|
| 11727 | class="cmtt-8"> 4.8260743e-07,</span><span
|
|---|
| 11728 | class="cmtt-8"> 5.1396998e-07,</span><span
|
|---|
| 11729 | class="cmtt-8"> 5.4737065e-07,</span><span
|
|---|
| 11730 | class="cmtt-8"> 5.8294187e-07,</span><br class="fancyvrb" /><a
|
|---|
| 11731 | id="x1-127016r8"></a><span
|
|---|
| 11732 | class="cmr-6">8</span><span
|
|---|
| 11733 | class="cmtt-8"> </span><span
|
|---|
| 11734 | class="cmtt-8"> 6.2082472e-07,</span><span
|
|---|
| 11735 | class="cmtt-8"> 6.6116941e-07,</span><span
|
|---|
| 11736 | class="cmtt-8"> 7.0413592e-07,</span><span
|
|---|
| 11737 | class="cmtt-8"> 7.4989464e-07,</span>
|
|---|
| 11738 | <br class="fancyvrb" /><a
|
|---|
| 11739 | id="x1-127018r9"></a><span
|
|---|
| 11740 | class="cmr-6">9</span><span
|
|---|
| 11741 | class="cmtt-8"> </span><span
|
|---|
| 11742 | class="cmtt-8"> 7.9862701e-07,</span><span
|
|---|
| 11743 | class="cmtt-8"> 8.5052630e-07,</span><span
|
|---|
| 11744 | class="cmtt-8"> 9.0579828e-07,</span><span
|
|---|
| 11745 | class="cmtt-8"> 9.6466216e-07,</span><br class="fancyvrb" /><a
|
|---|
| 11746 | id="x1-127020r10"></a><span
|
|---|
| 11747 | class="cmr-6">10</span><span
|
|---|
| 11748 | class="cmtt-8"> </span><span
|
|---|
| 11749 | class="cmtt-8"> 1.0273513e-06,</span><span
|
|---|
| 11750 | class="cmtt-8"> 1.0941144e-06,</span><span
|
|---|
| 11751 | class="cmtt-8"> 1.1652161e-06,</span><span
|
|---|
| 11752 | class="cmtt-8"> 1.2409384e-06,</span>
|
|---|
| 11753 | <br class="fancyvrb" /><a
|
|---|
| 11754 | id="x1-127022r11"></a><span
|
|---|
| 11755 | class="cmr-6">11</span><span
|
|---|
| 11756 | class="cmtt-8"> </span><span
|
|---|
| 11757 | class="cmtt-8"> 1.3215816e-06,</span><span
|
|---|
| 11758 | class="cmtt-8"> 1.4074654e-06,</span><span
|
|---|
| 11759 | class="cmtt-8"> 1.4989305e-06,</span><span
|
|---|
| 11760 | class="cmtt-8"> 1.5963394e-06,</span><br class="fancyvrb" /><a
|
|---|
| 11761 | id="x1-127024r12"></a><span
|
|---|
| 11762 | class="cmr-6">12</span><span
|
|---|
| 11763 | class="cmtt-8"> </span><span
|
|---|
| 11764 | class="cmtt-8"> 1.7000785e-06,</span><span
|
|---|
| 11765 | class="cmtt-8"> 1.8105592e-06,</span><span
|
|---|
| 11766 | class="cmtt-8"> 1.9282195e-06,</span><span
|
|---|
| 11767 | class="cmtt-8"> 2.0535261e-06,</span>
|
|---|
| 11768 | <br class="fancyvrb" /><a
|
|---|
| 11769 | id="x1-127026r13"></a><span
|
|---|
| 11770 | class="cmr-6">13</span><span
|
|---|
| 11771 | class="cmtt-8"> </span><span
|
|---|
| 11772 | class="cmtt-8"> 2.1869758e-06,</span><span
|
|---|
| 11773 | class="cmtt-8"> 2.3290978e-06,</span><span
|
|---|
| 11774 | class="cmtt-8"> 2.4804557e-06,</span><span
|
|---|
| 11775 | class="cmtt-8"> 2.6416497e-06,</span><br class="fancyvrb" /><a
|
|---|
| 11776 | id="x1-127028r14"></a><span
|
|---|
| 11777 | class="cmr-6">14</span><span
|
|---|
| 11778 | class="cmtt-8"> </span><span
|
|---|
| 11779 | class="cmtt-8"> 2.8133190e-06,</span><span
|
|---|
| 11780 | class="cmtt-8"> 2.9961443e-06,</span><span
|
|---|
| 11781 | class="cmtt-8"> 3.1908506e-06,</span><span
|
|---|
| 11782 | class="cmtt-8"> 3.3982101e-06,</span>
|
|---|
| 11783 | <br class="fancyvrb" /><a
|
|---|
| 11784 | id="x1-127030r15"></a><span
|
|---|
| 11785 | class="cmr-6">15</span><span
|
|---|
| 11786 | class="cmtt-8"> </span><span
|
|---|
| 11787 | class="cmtt-8"> 3.6190449e-06,</span><span
|
|---|
| 11788 | class="cmtt-8"> 3.8542308e-06,</span><span
|
|---|
| 11789 | class="cmtt-8"> 4.1047004e-06,</span><span
|
|---|
| 11790 | class="cmtt-8"> 4.3714470e-06,</span><br class="fancyvrb" /><a
|
|---|
| 11791 | id="x1-127032r16"></a><span
|
|---|
| 11792 | class="cmr-6">16</span><span
|
|---|
| 11793 | class="cmtt-8"> </span><span
|
|---|
| 11794 | class="cmtt-8"> 4.6555282e-06,</span><span
|
|---|
| 11795 | class="cmtt-8"> 4.9580707e-06,</span><span
|
|---|
| 11796 | class="cmtt-8"> 5.2802740e-06,</span><span
|
|---|
| 11797 | class="cmtt-8"> 5.6234160e-06,</span>
|
|---|
| 11798 | <br class="fancyvrb" /><a
|
|---|
| 11799 | id="x1-127034r17"></a><span
|
|---|
| 11800 | class="cmr-6">17</span><span
|
|---|
| 11801 | class="cmtt-8"> </span><span
|
|---|
| 11802 | class="cmtt-8"> 5.9888572e-06,</span><span
|
|---|
| 11803 | class="cmtt-8"> 6.3780469e-06,</span><span
|
|---|
| 11804 | class="cmtt-8"> 6.7925283e-06,</span><span
|
|---|
| 11805 | class="cmtt-8"> 7.2339451e-06,</span><br class="fancyvrb" /><a
|
|---|
| 11806 | id="x1-127036r18"></a><span
|
|---|
| 11807 | class="cmr-6">18</span><span
|
|---|
| 11808 | class="cmtt-8"> </span><span
|
|---|
| 11809 | class="cmtt-8"> 7.7040476e-06,</span><span
|
|---|
| 11810 | class="cmtt-8"> 8.2047000e-06,</span><span
|
|---|
| 11811 | class="cmtt-8"> 8.7378876e-06,</span><span
|
|---|
| 11812 | class="cmtt-8"> 9.3057248e-06,</span>
|
|---|
| 11813 | <br class="fancyvrb" /><a
|
|---|
| 11814 | id="x1-127038r19"></a><span
|
|---|
| 11815 | class="cmr-6">19</span><span
|
|---|
| 11816 | class="cmtt-8"> </span><span
|
|---|
| 11817 | class="cmtt-8"> 9.9104632e-06,</span><span
|
|---|
| 11818 | class="cmtt-8"> 1.0554501e-05,</span><span
|
|---|
| 11819 | class="cmtt-8"> 1.1240392e-05,</span><span
|
|---|
| 11820 | class="cmtt-8"> 1.1970856e-05,</span><br class="fancyvrb" /><a
|
|---|
| 11821 | id="x1-127040r20"></a><span
|
|---|
| 11822 | class="cmr-6">20</span><span
|
|---|
| 11823 | class="cmtt-8"> </span><span
|
|---|
| 11824 | class="cmtt-8"> 1.2748789e-05,</span><span
|
|---|
| 11825 | class="cmtt-8"> 1.3577278e-05,</span><span
|
|---|
| 11826 | class="cmtt-8"> 1.4459606e-05,</span><span
|
|---|
| 11827 | class="cmtt-8"> 1.5399272e-05,</span>
|
|---|
| 11828 | <br class="fancyvrb" /><a
|
|---|
| 11829 | id="x1-127042r21"></a><span
|
|---|
| 11830 | class="cmr-6">21</span><span
|
|---|
| 11831 | class="cmtt-8"> </span><span
|
|---|
| 11832 | class="cmtt-8"> 1.6400004e-05,</span><span
|
|---|
| 11833 | class="cmtt-8"> 1.7465768e-05,</span><span
|
|---|
| 11834 | class="cmtt-8"> 1.8600792e-05,</span><span
|
|---|
| 11835 | class="cmtt-8"> 1.9809576e-05,</span><br class="fancyvrb" /><a
|
|---|
| 11836 | id="x1-127044r22"></a><span
|
|---|
| 11837 | class="cmr-6">22</span><span
|
|---|
| 11838 | class="cmtt-8"> </span><span
|
|---|
| 11839 | class="cmtt-8"> 2.1096914e-05,</span><span
|
|---|
| 11840 | class="cmtt-8"> 2.2467911e-05,</span><span
|
|---|
| 11841 | class="cmtt-8"> 2.3928002e-05,</span><span
|
|---|
| 11842 | class="cmtt-8"> 2.5482978e-05,</span>
|
|---|
| 11843 | <br class="fancyvrb" /><a
|
|---|
| 11844 | id="x1-127046r23"></a><span
|
|---|
| 11845 | class="cmr-6">23</span><span
|
|---|
| 11846 | class="cmtt-8"> </span><span
|
|---|
| 11847 | class="cmtt-8"> 2.7139006e-05,</span><span
|
|---|
| 11848 | class="cmtt-8"> 2.8902651e-05,</span><span
|
|---|
| 11849 | class="cmtt-8"> 3.0780908e-05,</span><span
|
|---|
| 11850 | class="cmtt-8"> 3.2781225e-05,</span><br class="fancyvrb" /><a
|
|---|
| 11851 | id="x1-127048r24"></a><span
|
|---|
| 11852 | class="cmr-6">24</span><span
|
|---|
| 11853 | class="cmtt-8"> </span><span
|
|---|
| 11854 | class="cmtt-8"> 3.4911534e-05,</span><span
|
|---|
| 11855 | class="cmtt-8"> 3.7180282e-05,</span><span
|
|---|
| 11856 | class="cmtt-8"> 3.9596466e-05,</span><span
|
|---|
| 11857 | class="cmtt-8"> 4.2169667e-05,</span>
|
|---|
| 11858 | <br class="fancyvrb" /><a
|
|---|
| 11859 | id="x1-127050r25"></a><span
|
|---|
| 11860 | class="cmr-6">25</span><span
|
|---|
| 11861 | class="cmtt-8"> </span><span
|
|---|
| 11862 | class="cmtt-8"> 4.4910090e-05,</span><span
|
|---|
| 11863 | class="cmtt-8"> 4.7828601e-05,</span><span
|
|---|
| 11864 | class="cmtt-8"> 5.0936773e-05,</span><span
|
|---|
| 11865 | class="cmtt-8"> 5.4246931e-05,</span><br class="fancyvrb" /><a
|
|---|
| 11866 | id="x1-127052r26"></a><span
|
|---|
| 11867 | class="cmr-6">26</span><span
|
|---|
| 11868 | class="cmtt-8"> </span><span
|
|---|
| 11869 | class="cmtt-8"> 5.7772202e-05,</span><span
|
|---|
| 11870 | class="cmtt-8"> 6.1526565e-05,</span><span
|
|---|
| 11871 | class="cmtt-8"> 6.5524908e-05,</span><span
|
|---|
| 11872 | class="cmtt-8"> 6.9783085e-05,</span>
|
|---|
| 11873 | <br class="fancyvrb" /><a
|
|---|
| 11874 | id="x1-127054r27"></a><span
|
|---|
| 11875 | class="cmr-6">27</span><span
|
|---|
| 11876 | class="cmtt-8"> </span><span
|
|---|
| 11877 | class="cmtt-8"> 7.4317983e-05,</span><span
|
|---|
| 11878 | class="cmtt-8"> 7.9147585e-05,</span><span
|
|---|
| 11879 | class="cmtt-8"> 8.4291040e-05,</span><span
|
|---|
| 11880 | class="cmtt-8"> 8.9768747e-05,</span><br class="fancyvrb" /><a
|
|---|
| 11881 | id="x1-127056r28"></a><span
|
|---|
| 11882 | class="cmr-6">28</span><span
|
|---|
| 11883 | class="cmtt-8"> </span><span
|
|---|
| 11884 | class="cmtt-8"> 9.5602426e-05,</span><span
|
|---|
| 11885 | class="cmtt-8"> 0.00010181521,</span><span
|
|---|
| 11886 | class="cmtt-8"> 0.00010843174,</span><span
|
|---|
| 11887 | class="cmtt-8"> 0.00011547824,</span>
|
|---|
| 11888 | <br class="fancyvrb" /><a
|
|---|
| 11889 | id="x1-127058r29"></a><span
|
|---|
| 11890 | class="cmr-6">29</span><span
|
|---|
| 11891 | class="cmtt-8"> </span><span
|
|---|
| 11892 | class="cmtt-8"> 0.00012298267,</span><span
|
|---|
| 11893 | class="cmtt-8"> 0.00013097477,</span><span
|
|---|
| 11894 | class="cmtt-8"> 0.00013948625,</span><span
|
|---|
| 11895 | class="cmtt-8"> 0.00014855085,</span><br class="fancyvrb" /><a
|
|---|
| 11896 | id="x1-127060r30"></a><span
|
|---|
| 11897 | class="cmr-6">30</span><span
|
|---|
| 11898 | class="cmtt-8"> </span><span
|
|---|
| 11899 | class="cmtt-8"> 0.00015820453,</span><span
|
|---|
| 11900 | class="cmtt-8"> 0.00016848555,</span><span
|
|---|
| 11901 | class="cmtt-8"> 0.00017943469,</span><span
|
|---|
| 11902 | class="cmtt-8"> 0.00019109536,</span>
|
|---|
| 11903 | <br class="fancyvrb" /><a
|
|---|
| 11904 | id="x1-127062r31"></a><span
|
|---|
| 11905 | class="cmr-6">31</span><span
|
|---|
| 11906 | class="cmtt-8"> </span><span
|
|---|
| 11907 | class="cmtt-8"> 0.00020351382,</span><span
|
|---|
| 11908 | class="cmtt-8"> 0.00021673929,</span><span
|
|---|
| 11909 | class="cmtt-8"> 0.00023082423,</span><span
|
|---|
| 11910 | class="cmtt-8"> 0.00024582449,</span><br class="fancyvrb" /><a
|
|---|
| 11911 | id="x1-127064r32"></a><span
|
|---|
| 11912 | class="cmr-6">32</span><span
|
|---|
| 11913 | class="cmtt-8"> </span><span
|
|---|
| 11914 | class="cmtt-8"> 0.00026179955,</span><span
|
|---|
| 11915 | class="cmtt-8"> 0.00027881276,</span><span
|
|---|
| 11916 | class="cmtt-8"> 0.00029693158,</span><span
|
|---|
| 11917 | class="cmtt-8"> 0.00031622787,</span>
|
|---|
| 11918 | <br class="fancyvrb" /><a
|
|---|
| 11919 | id="x1-127066r33"></a><span
|
|---|
| 11920 | class="cmr-6">33</span><span
|
|---|
| 11921 | class="cmtt-8"> </span><span
|
|---|
| 11922 | class="cmtt-8"> 0.00033677814,</span><span
|
|---|
| 11923 | class="cmtt-8"> 0.00035866388,</span><span
|
|---|
| 11924 | class="cmtt-8"> 0.00038197188,</span><span
|
|---|
| 11925 | class="cmtt-8"> 0.00040679456,</span><br class="fancyvrb" /><a
|
|---|
| 11926 | id="x1-127068r34"></a><span
|
|---|
| 11927 | class="cmr-6">34</span><span
|
|---|
| 11928 | class="cmtt-8"> </span><span
|
|---|
| 11929 | class="cmtt-8"> 0.00043323036,</span><span
|
|---|
| 11930 | class="cmtt-8"> 0.00046138411,</span><span
|
|---|
| 11931 | class="cmtt-8"> 0.00049136745,</span><span
|
|---|
| 11932 | class="cmtt-8"> 0.00052329927,</span>
|
|---|
| 11933 | <br class="fancyvrb" /><a
|
|---|
| 11934 | id="x1-127070r35"></a><span
|
|---|
| 11935 | class="cmr-6">35</span><span
|
|---|
| 11936 | class="cmtt-8"> </span><span
|
|---|
| 11937 | class="cmtt-8"> 0.00055730621,</span><span
|
|---|
| 11938 | class="cmtt-8"> 0.00059352311,</span><span
|
|---|
| 11939 | class="cmtt-8"> 0.00063209358,</span><span
|
|---|
| 11940 | class="cmtt-8"> 0.00067317058,</span><br class="fancyvrb" /><a
|
|---|
| 11941 | id="x1-127072r36"></a><span
|
|---|
| 11942 | class="cmr-6">36</span><span
|
|---|
| 11943 | class="cmtt-8"> </span><span
|
|---|
| 11944 | class="cmtt-8"> 0.00071691700,</span><span
|
|---|
| 11945 | class="cmtt-8"> 0.00076350630,</span><span
|
|---|
| 11946 | class="cmtt-8"> 0.00081312324,</span><span
|
|---|
| 11947 | class="cmtt-8"> 0.00086596457,</span>
|
|---|
| 11948 | <br class="fancyvrb" /><a
|
|---|
| 11949 | id="x1-127074r37"></a><span
|
|---|
| 11950 | class="cmr-6">37</span><span
|
|---|
| 11951 | class="cmtt-8"> </span><span
|
|---|
| 11952 | class="cmtt-8"> 0.00092223983,</span><span
|
|---|
| 11953 | class="cmtt-8"> 0.00098217216,</span><span
|
|---|
| 11954 | class="cmtt-8"> 0.0010459992,</span><span
|
|---|
| 11955 | class="cmtt-8"> </span><span
|
|---|
| 11956 | class="cmtt-8"> 0.0011139742,</span><br class="fancyvrb" /><a
|
|---|
| 11957 | id="x1-127076r38"></a><span
|
|---|
| 11958 | class="cmr-6">38</span><span
|
|---|
| 11959 | class="cmtt-8"> </span><span
|
|---|
| 11960 | class="cmtt-8"> 0.0011863665,</span><span
|
|---|
| 11961 | class="cmtt-8"> </span><span
|
|---|
| 11962 | class="cmtt-8"> 0.0012634633,</span><span
|
|---|
| 11963 | class="cmtt-8"> </span><span
|
|---|
| 11964 | class="cmtt-8"> 0.0013455702,</span><span
|
|---|
| 11965 | class="cmtt-8"> </span><span
|
|---|
| 11966 | class="cmtt-8"> 0.0014330129,</span>
|
|---|
| 11967 | <br class="fancyvrb" /><a
|
|---|
| 11968 | id="x1-127078r39"></a><span
|
|---|
| 11969 | class="cmr-6">39</span><span
|
|---|
| 11970 | class="cmtt-8"> </span><span
|
|---|
| 11971 | class="cmtt-8"> 0.0015261382,</span><span
|
|---|
| 11972 | class="cmtt-8"> </span><span
|
|---|
| 11973 | class="cmtt-8"> 0.0016253153,</span><span
|
|---|
| 11974 | class="cmtt-8"> </span><span
|
|---|
| 11975 | class="cmtt-8"> 0.0017309374,</span><span
|
|---|
| 11976 | class="cmtt-8"> </span><span
|
|---|
| 11977 | class="cmtt-8"> 0.0018434235,</span><br class="fancyvrb" /><a
|
|---|
| 11978 | id="x1-127080r40"></a><span
|
|---|
| 11979 | class="cmr-6">40</span><span
|
|---|
| 11980 | class="cmtt-8"> </span><span
|
|---|
| 11981 | class="cmtt-8"> 0.0019632195,</span><span
|
|---|
| 11982 | class="cmtt-8"> </span><span
|
|---|
| 11983 | class="cmtt-8"> 0.0020908006,</span><span
|
|---|
| 11984 | class="cmtt-8"> </span><span
|
|---|
| 11985 | class="cmtt-8"> 0.0022266726,</span><span
|
|---|
| 11986 | class="cmtt-8"> </span><span
|
|---|
| 11987 | class="cmtt-8"> 0.0023713743,</span>
|
|---|
| 11988 | <br class="fancyvrb" /><a
|
|---|
| 11989 | id="x1-127082r41"></a><span
|
|---|
| 11990 | class="cmr-6">41</span><span
|
|---|
| 11991 | class="cmtt-8"> </span><span
|
|---|
| 11992 | class="cmtt-8"> 0.0025254795,</span><span
|
|---|
| 11993 | class="cmtt-8"> </span><span
|
|---|
| 11994 | class="cmtt-8"> 0.0026895994,</span><span
|
|---|
| 11995 | class="cmtt-8"> </span><span
|
|---|
| 11996 | class="cmtt-8"> 0.0028643847,</span><span
|
|---|
| 11997 | class="cmtt-8"> </span><span
|
|---|
| 11998 | class="cmtt-8"> 0.0030505286,</span><br class="fancyvrb" /><a
|
|---|
| 11999 | id="x1-127084r42"></a><span
|
|---|
| 12000 | class="cmr-6">42</span><span
|
|---|
| 12001 | class="cmtt-8"> </span><span
|
|---|
| 12002 | class="cmtt-8"> 0.0032487691,</span><span
|
|---|
| 12003 | class="cmtt-8"> </span><span
|
|---|
| 12004 | class="cmtt-8"> 0.0034598925,</span><span
|
|---|
| 12005 | class="cmtt-8"> </span><span
|
|---|
| 12006 | class="cmtt-8"> 0.0036847358,</span><span
|
|---|
| 12007 | class="cmtt-8"> </span><span
|
|---|
| 12008 | class="cmtt-8"> 0.0039241906,</span>
|
|---|
| 12009 | <br class="fancyvrb" /><a
|
|---|
| 12010 | id="x1-127086r43"></a><span
|
|---|
| 12011 | class="cmr-6">43</span><span
|
|---|
| 12012 | class="cmtt-8"> </span><span
|
|---|
| 12013 | class="cmtt-8"> 0.0041792066,</span><span
|
|---|
| 12014 | class="cmtt-8"> </span><span
|
|---|
| 12015 | class="cmtt-8"> 0.0044507950,</span><span
|
|---|
| 12016 | class="cmtt-8"> </span><span
|
|---|
| 12017 | class="cmtt-8"> 0.0047400328,</span><span
|
|---|
| 12018 | class="cmtt-8"> </span><span
|
|---|
| 12019 | class="cmtt-8"> 0.0050480668,</span><br class="fancyvrb" /><a
|
|---|
| 12020 | id="x1-127088r44"></a><span
|
|---|
| 12021 | class="cmr-6">44</span><span
|
|---|
| 12022 | class="cmtt-8"> </span><span
|
|---|
| 12023 | class="cmtt-8"> 0.0053761186,</span><span
|
|---|
| 12024 | class="cmtt-8"> </span><span
|
|---|
| 12025 | class="cmtt-8"> 0.0057254891,</span><span
|
|---|
| 12026 | class="cmtt-8"> </span><span
|
|---|
| 12027 | class="cmtt-8"> 0.0060975636,</span><span
|
|---|
| 12028 | class="cmtt-8"> </span><span
|
|---|
| 12029 | class="cmtt-8"> 0.0064938176,</span>
|
|---|
| 12030 | <br class="fancyvrb" /><a
|
|---|
| 12031 | id="x1-127090r45"></a><span
|
|---|
| 12032 | class="cmr-6">45</span><span
|
|---|
| 12033 | class="cmtt-8"> </span><span
|
|---|
| 12034 | class="cmtt-8"> 0.0069158225,</span><span
|
|---|
| 12035 | class="cmtt-8"> </span><span
|
|---|
| 12036 | class="cmtt-8"> 0.0073652516,</span><span
|
|---|
| 12037 | class="cmtt-8"> </span><span
|
|---|
| 12038 | class="cmtt-8"> 0.0078438871,</span><span
|
|---|
| 12039 | class="cmtt-8"> </span><span
|
|---|
| 12040 | class="cmtt-8"> 0.0083536271,</span><br class="fancyvrb" /><a
|
|---|
| 12041 | id="x1-127092r46"></a><span
|
|---|
| 12042 | class="cmr-6">46</span><span
|
|---|
| 12043 | class="cmtt-8"> </span><span
|
|---|
| 12044 | class="cmtt-8"> 0.0088964928,</span><span
|
|---|
| 12045 | class="cmtt-8"> </span><span
|
|---|
| 12046 | class="cmtt-8"> 0.009474637,</span><span
|
|---|
| 12047 | class="cmtt-8"> </span><span
|
|---|
| 12048 | class="cmtt-8"> </span><span
|
|---|
| 12049 | class="cmtt-8"> 0.010090352,</span><span
|
|---|
| 12050 | class="cmtt-8"> </span><span
|
|---|
| 12051 | class="cmtt-8"> </span><span
|
|---|
| 12052 | class="cmtt-8"> 0.010746080,</span>
|
|---|
| 12053 | <br class="fancyvrb" /><a
|
|---|
| 12054 | id="x1-127094r47"></a><span
|
|---|
| 12055 | class="cmr-6">47</span><span
|
|---|
| 12056 | class="cmtt-8"> </span><span
|
|---|
| 12057 | class="cmtt-8"> 0.011444421,</span><span
|
|---|
| 12058 | class="cmtt-8"> </span><span
|
|---|
| 12059 | class="cmtt-8"> </span><span
|
|---|
| 12060 | class="cmtt-8"> 0.012188144,</span><span
|
|---|
| 12061 | class="cmtt-8"> </span><span
|
|---|
| 12062 | class="cmtt-8"> </span><span
|
|---|
| 12063 | class="cmtt-8"> 0.012980198,</span><span
|
|---|
| 12064 | class="cmtt-8"> </span><span
|
|---|
| 12065 | class="cmtt-8"> </span><span
|
|---|
| 12066 | class="cmtt-8"> 0.013823725,</span><br class="fancyvrb" /><a
|
|---|
| 12067 | id="x1-127096r48"></a><span
|
|---|
| 12068 | class="cmr-6">48</span><span
|
|---|
| 12069 | class="cmtt-8"> </span><span
|
|---|
| 12070 | class="cmtt-8"> 0.014722068,</span><span
|
|---|
| 12071 | class="cmtt-8"> </span><span
|
|---|
| 12072 | class="cmtt-8"> </span><span
|
|---|
| 12073 | class="cmtt-8"> 0.015678791,</span><span
|
|---|
| 12074 | class="cmtt-8"> </span><span
|
|---|
| 12075 | class="cmtt-8"> </span><span
|
|---|
| 12076 | class="cmtt-8"> 0.016697687,</span><span
|
|---|
| 12077 | class="cmtt-8"> </span><span
|
|---|
| 12078 | class="cmtt-8"> </span><span
|
|---|
| 12079 | class="cmtt-8"> 0.017782797,</span>
|
|---|
| 12080 | <br class="fancyvrb" /><a
|
|---|
| 12081 | id="x1-127098r49"></a><span
|
|---|
| 12082 | class="cmr-6">49</span><span
|
|---|
| 12083 | class="cmtt-8"> </span><span
|
|---|
| 12084 | class="cmtt-8"> 0.018938423,</span><span
|
|---|
| 12085 | class="cmtt-8"> </span><span
|
|---|
| 12086 | class="cmtt-8"> </span><span
|
|---|
| 12087 | class="cmtt-8"> 0.020169149,</span><span
|
|---|
| 12088 | class="cmtt-8"> </span><span
|
|---|
| 12089 | class="cmtt-8"> </span><span
|
|---|
| 12090 | class="cmtt-8"> 0.021479854,</span><span
|
|---|
| 12091 | class="cmtt-8"> </span><span
|
|---|
| 12092 | class="cmtt-8"> </span><span
|
|---|
| 12093 | class="cmtt-8"> 0.022875735,</span><br class="fancyvrb" /><a
|
|---|
| 12094 | id="x1-127100r50"></a><span
|
|---|
| 12095 | class="cmr-6">50</span><span
|
|---|
| 12096 | class="cmtt-8"> </span><span
|
|---|
| 12097 | class="cmtt-8"> 0.024362330,</span><span
|
|---|
| 12098 | class="cmtt-8"> </span><span
|
|---|
| 12099 | class="cmtt-8"> </span><span
|
|---|
| 12100 | class="cmtt-8"> 0.025945531,</span><span
|
|---|
| 12101 | class="cmtt-8"> </span><span
|
|---|
| 12102 | class="cmtt-8"> </span><span
|
|---|
| 12103 | class="cmtt-8"> 0.027631618,</span><span
|
|---|
| 12104 | class="cmtt-8"> </span><span
|
|---|
| 12105 | class="cmtt-8"> </span><span
|
|---|
| 12106 | class="cmtt-8"> 0.029427276,</span>
|
|---|
| 12107 | <br class="fancyvrb" /><a
|
|---|
| 12108 | id="x1-127102r51"></a><span
|
|---|
| 12109 | class="cmr-6">51</span><span
|
|---|
| 12110 | class="cmtt-8"> </span><span
|
|---|
| 12111 | class="cmtt-8"> 0.031339626,</span><span
|
|---|
| 12112 | class="cmtt-8"> </span><span
|
|---|
| 12113 | class="cmtt-8"> </span><span
|
|---|
| 12114 | class="cmtt-8"> 0.033376252,</span><span
|
|---|
| 12115 | class="cmtt-8"> </span><span
|
|---|
| 12116 | class="cmtt-8"> </span><span
|
|---|
| 12117 | class="cmtt-8"> 0.035545228,</span><span
|
|---|
| 12118 | class="cmtt-8"> </span><span
|
|---|
| 12119 | class="cmtt-8"> </span><span
|
|---|
| 12120 | class="cmtt-8"> 0.037855157,</span><br class="fancyvrb" /><a
|
|---|
| 12121 | id="x1-127104r52"></a><span
|
|---|
| 12122 | class="cmr-6">52</span><span
|
|---|
| 12123 | class="cmtt-8"> </span><span
|
|---|
| 12124 | class="cmtt-8"> 0.040315199,</span><span
|
|---|
| 12125 | class="cmtt-8"> </span><span
|
|---|
| 12126 | class="cmtt-8"> </span><span
|
|---|
| 12127 | class="cmtt-8"> 0.042935108,</span><span
|
|---|
| 12128 | class="cmtt-8"> </span><span
|
|---|
| 12129 | class="cmtt-8"> </span><span
|
|---|
| 12130 | class="cmtt-8"> 0.045725273,</span><span
|
|---|
| 12131 | class="cmtt-8"> </span><span
|
|---|
| 12132 | class="cmtt-8"> </span><span
|
|---|
| 12133 | class="cmtt-8"> 0.048696758,</span>
|
|---|
| 12134 | <br class="fancyvrb" /><a
|
|---|
| 12135 | id="x1-127106r53"></a><span
|
|---|
| 12136 | class="cmr-6">53</span><span
|
|---|
| 12137 | class="cmtt-8"> </span><span
|
|---|
| 12138 | class="cmtt-8"> 0.051861348,</span><span
|
|---|
| 12139 | class="cmtt-8"> </span><span
|
|---|
| 12140 | class="cmtt-8"> </span><span
|
|---|
| 12141 | class="cmtt-8"> 0.055231591,</span><span
|
|---|
| 12142 | class="cmtt-8"> </span><span
|
|---|
| 12143 | class="cmtt-8"> </span><span
|
|---|
| 12144 | class="cmtt-8"> 0.058820850,</span><span
|
|---|
| 12145 | class="cmtt-8"> </span><span
|
|---|
| 12146 | class="cmtt-8"> </span><span
|
|---|
| 12147 | class="cmtt-8"> 0.062643361,</span><br class="fancyvrb" /><a
|
|---|
| 12148 | id="x1-127108r54"></a><span
|
|---|
| 12149 | class="cmr-6">54</span><span
|
|---|
| 12150 | class="cmtt-8"> </span><span
|
|---|
| 12151 | class="cmtt-8"> 0.066714279,</span><span
|
|---|
| 12152 | class="cmtt-8"> </span><span
|
|---|
| 12153 | class="cmtt-8"> </span><span
|
|---|
| 12154 | class="cmtt-8"> 0.071049749,</span><span
|
|---|
| 12155 | class="cmtt-8"> </span><span
|
|---|
| 12156 | class="cmtt-8"> </span><span
|
|---|
| 12157 | class="cmtt-8"> 0.075666962,</span><span
|
|---|
| 12158 | class="cmtt-8"> </span><span
|
|---|
| 12159 | class="cmtt-8"> </span><span
|
|---|
| 12160 | class="cmtt-8"> 0.080584227,</span>
|
|---|
| 12161 | <br class="fancyvrb" /><a
|
|---|
| 12162 | id="x1-127110r55"></a><span
|
|---|
| 12163 | class="cmr-6">55</span><span
|
|---|
| 12164 | class="cmtt-8"> </span><span
|
|---|
| 12165 | class="cmtt-8"> 0.085821044,</span><span
|
|---|
| 12166 | class="cmtt-8"> </span><span
|
|---|
| 12167 | class="cmtt-8"> </span><span
|
|---|
| 12168 | class="cmtt-8"> 0.091398179,</span><span
|
|---|
| 12169 | class="cmtt-8"> </span><span
|
|---|
| 12170 | class="cmtt-8"> </span><span
|
|---|
| 12171 | class="cmtt-8"> 0.097337747,</span><span
|
|---|
| 12172 | class="cmtt-8"> </span><span
|
|---|
| 12173 | class="cmtt-8"> </span><span
|
|---|
| 12174 | class="cmtt-8"> 0.10366330,</span><br class="fancyvrb" /><a
|
|---|
| 12175 | id="x1-127112r56"></a><span
|
|---|
| 12176 | class="cmr-6">56</span><span
|
|---|
| 12177 | class="cmtt-8"> </span><span
|
|---|
| 12178 | class="cmtt-8"> 0.11039993,</span><span
|
|---|
| 12179 | class="cmtt-8"> </span><span
|
|---|
| 12180 | class="cmtt-8"> </span><span
|
|---|
| 12181 | class="cmtt-8"> </span><span
|
|---|
| 12182 | class="cmtt-8"> 0.11757434,</span><span
|
|---|
| 12183 | class="cmtt-8"> </span><span
|
|---|
| 12184 | class="cmtt-8"> </span><span
|
|---|
| 12185 | class="cmtt-8"> </span><span
|
|---|
| 12186 | class="cmtt-8"> 0.12521498,</span><span
|
|---|
| 12187 | class="cmtt-8"> </span><span
|
|---|
| 12188 | class="cmtt-8"> </span><span
|
|---|
| 12189 | class="cmtt-8"> </span><span
|
|---|
| 12190 | class="cmtt-8"> 0.13335215,</span>
|
|---|
| 12191 | <br class="fancyvrb" /><a
|
|---|
| 12192 | id="x1-127114r57"></a><span
|
|---|
| 12193 | class="cmr-6">57</span><span
|
|---|
| 12194 | class="cmtt-8"> </span><span
|
|---|
| 12195 | class="cmtt-8"> 0.14201813,</span><span
|
|---|
| 12196 | class="cmtt-8"> </span><span
|
|---|
| 12197 | class="cmtt-8"> </span><span
|
|---|
| 12198 | class="cmtt-8"> </span><span
|
|---|
| 12199 | class="cmtt-8"> 0.15124727,</span><span
|
|---|
| 12200 | class="cmtt-8"> </span><span
|
|---|
| 12201 | class="cmtt-8"> </span><span
|
|---|
| 12202 | class="cmtt-8"> </span><span
|
|---|
| 12203 | class="cmtt-8"> 0.16107617,</span><span
|
|---|
| 12204 | class="cmtt-8"> </span><span
|
|---|
| 12205 | class="cmtt-8"> </span><span
|
|---|
| 12206 | class="cmtt-8"> </span><span
|
|---|
| 12207 | class="cmtt-8"> 0.17154380,</span><br class="fancyvrb" /><a
|
|---|
| 12208 | id="x1-127116r58"></a><span
|
|---|
| 12209 | class="cmr-6">58</span><span
|
|---|
| 12210 | class="cmtt-8"> </span><span
|
|---|
| 12211 | class="cmtt-8"> 0.18269168,</span><span
|
|---|
| 12212 | class="cmtt-8"> </span><span
|
|---|
| 12213 | class="cmtt-8"> </span><span
|
|---|
| 12214 | class="cmtt-8"> </span><span
|
|---|
| 12215 | class="cmtt-8"> 0.19456402,</span><span
|
|---|
| 12216 | class="cmtt-8"> </span><span
|
|---|
| 12217 | class="cmtt-8"> </span><span
|
|---|
| 12218 | class="cmtt-8"> </span><span
|
|---|
| 12219 | class="cmtt-8"> 0.20720788,</span><span
|
|---|
| 12220 | class="cmtt-8"> </span><span
|
|---|
| 12221 | class="cmtt-8"> </span><span
|
|---|
| 12222 | class="cmtt-8"> </span><span
|
|---|
| 12223 | class="cmtt-8"> 0.22067342,</span>
|
|---|
| 12224 | <br class="fancyvrb" /><a
|
|---|
| 12225 | id="x1-127118r59"></a><span
|
|---|
| 12226 | class="cmr-6">59</span><span
|
|---|
| 12227 | class="cmtt-8"> </span><span
|
|---|
| 12228 | class="cmtt-8"> 0.23501402,</span><span
|
|---|
| 12229 | class="cmtt-8"> </span><span
|
|---|
| 12230 | class="cmtt-8"> </span><span
|
|---|
| 12231 | class="cmtt-8"> </span><span
|
|---|
| 12232 | class="cmtt-8"> 0.25028656,</span><span
|
|---|
| 12233 | class="cmtt-8"> </span><span
|
|---|
| 12234 | class="cmtt-8"> </span><span
|
|---|
| 12235 | class="cmtt-8"> </span><span
|
|---|
| 12236 | class="cmtt-8"> 0.26655159,</span><span
|
|---|
| 12237 | class="cmtt-8"> </span><span
|
|---|
| 12238 | class="cmtt-8"> </span><span
|
|---|
| 12239 | class="cmtt-8"> </span><span
|
|---|
| 12240 | class="cmtt-8"> 0.28387361,</span><br class="fancyvrb" /><a
|
|---|
| 12241 | id="x1-127120r60"></a><span
|
|---|
| 12242 | class="cmr-6">60</span><span
|
|---|
| 12243 | class="cmtt-8"> </span><span
|
|---|
| 12244 | class="cmtt-8"> 0.30232132,</span><span
|
|---|
| 12245 | class="cmtt-8"> </span><span
|
|---|
| 12246 | class="cmtt-8"> </span><span
|
|---|
| 12247 | class="cmtt-8"> </span><span
|
|---|
| 12248 | class="cmtt-8"> 0.32196786,</span><span
|
|---|
| 12249 | class="cmtt-8"> </span><span
|
|---|
| 12250 | class="cmtt-8"> </span><span
|
|---|
| 12251 | class="cmtt-8"> </span><span
|
|---|
| 12252 | class="cmtt-8"> 0.34289114,</span><span
|
|---|
| 12253 | class="cmtt-8"> </span><span
|
|---|
| 12254 | class="cmtt-8"> </span><span
|
|---|
| 12255 | class="cmtt-8"> </span><span
|
|---|
| 12256 | class="cmtt-8"> 0.36517414,</span>
|
|---|
| 12257 | <br class="fancyvrb" /><a
|
|---|
| 12258 | id="x1-127122r61"></a><span
|
|---|
| 12259 | class="cmr-6">61</span><span
|
|---|
| 12260 | class="cmtt-8"> </span><span
|
|---|
| 12261 | class="cmtt-8"> 0.38890521,</span><span
|
|---|
| 12262 | class="cmtt-8"> </span><span
|
|---|
| 12263 | class="cmtt-8"> </span><span
|
|---|
| 12264 | class="cmtt-8"> </span><span
|
|---|
| 12265 | class="cmtt-8"> 0.41417847,</span><span
|
|---|
| 12266 | class="cmtt-8"> </span><span
|
|---|
| 12267 | class="cmtt-8"> </span><span
|
|---|
| 12268 | class="cmtt-8"> </span><span
|
|---|
| 12269 | class="cmtt-8"> 0.44109412,</span><span
|
|---|
| 12270 | class="cmtt-8"> </span><span
|
|---|
| 12271 | class="cmtt-8"> </span><span
|
|---|
| 12272 | class="cmtt-8"> </span><span
|
|---|
| 12273 | class="cmtt-8"> 0.46975890,</span><br class="fancyvrb" /><a
|
|---|
| 12274 | id="x1-127124r62"></a><span
|
|---|
| 12275 | class="cmr-6">62</span><span
|
|---|
| 12276 | class="cmtt-8"> </span><span
|
|---|
| 12277 | class="cmtt-8"> 0.50028648,</span><span
|
|---|
| 12278 | class="cmtt-8"> </span><span
|
|---|
| 12279 | class="cmtt-8"> </span><span
|
|---|
| 12280 | class="cmtt-8"> </span><span
|
|---|
| 12281 | class="cmtt-8"> 0.53279791,</span><span
|
|---|
| 12282 | class="cmtt-8"> </span><span
|
|---|
| 12283 | class="cmtt-8"> </span><span
|
|---|
| 12284 | class="cmtt-8"> </span><span
|
|---|
| 12285 | class="cmtt-8"> 0.56742212,</span><span
|
|---|
| 12286 | class="cmtt-8"> </span><span
|
|---|
| 12287 | class="cmtt-8"> </span><span
|
|---|
| 12288 | class="cmtt-8"> </span><span
|
|---|
| 12289 | class="cmtt-8"> 0.60429640,</span>
|
|---|
| 12290 | <br class="fancyvrb" /><a
|
|---|
| 12291 | id="x1-127126r63"></a><span
|
|---|
| 12292 | class="cmr-6">63</span><span
|
|---|
| 12293 | class="cmtt-8"> </span><span
|
|---|
| 12294 | class="cmtt-8"> 0.64356699,</span><span
|
|---|
| 12295 | class="cmtt-8"> </span><span
|
|---|
| 12296 | class="cmtt-8"> </span><span
|
|---|
| 12297 | class="cmtt-8"> </span><span
|
|---|
| 12298 | class="cmtt-8"> 0.68538959,</span><span
|
|---|
| 12299 | class="cmtt-8"> </span><span
|
|---|
| 12300 | class="cmtt-8"> </span><span
|
|---|
| 12301 | class="cmtt-8"> </span><span
|
|---|
| 12302 | class="cmtt-8"> 0.72993007,</span><span
|
|---|
| 12303 | class="cmtt-8"> </span><span
|
|---|
| 12304 | class="cmtt-8"> </span><span
|
|---|
| 12305 | class="cmtt-8"> </span><span
|
|---|
| 12306 | class="cmtt-8"> 0.77736504,</span><br class="fancyvrb" /><a
|
|---|
| 12307 | id="x1-127128r64"></a><span
|
|---|
| 12308 | class="cmr-6">64</span><span
|
|---|
| 12309 | class="cmtt-8"> </span><span
|
|---|
| 12310 | class="cmtt-8"> 0.82788260,</span><span
|
|---|
| 12311 | class="cmtt-8"> </span><span
|
|---|
| 12312 | class="cmtt-8"> </span><span
|
|---|
| 12313 | class="cmtt-8"> </span><span
|
|---|
| 12314 | class="cmtt-8"> 0.88168307,</span><span
|
|---|
| 12315 | class="cmtt-8"> </span><span
|
|---|
| 12316 | class="cmtt-8"> </span><span
|
|---|
| 12317 | class="cmtt-8"> </span><span
|
|---|
| 12318 | class="cmtt-8"> 0.9389798,</span><span
|
|---|
| 12319 | class="cmtt-8"> </span><span
|
|---|
| 12320 | class="cmtt-8"> </span><span
|
|---|
| 12321 | class="cmtt-8"> </span><span
|
|---|
| 12322 | class="cmtt-8"> </span><span
|
|---|
| 12323 | class="cmtt-8"> 1.</span></div>
|
|---|
| 12324 |
|
|---|
| 12325 |
|
|---|
| 12326 |
|
|---|
| 12327 |
|
|---|
| 12328 |
|
|---|
| 12329 |
|
|---|
| 12330 | <h3 class="sectionHead"><span class="titlemark">A. </span> <a
|
|---|
| 12331 | id="x1-128000A"></a>Embedding Vorbis into an Ogg stream</h3>
|
|---|
| 12332 | <!--l. 5--><p class="noindent" >
|
|---|
| 12333 | <h4 class="subsectionHead"><span class="titlemark">A.1. </span> <a
|
|---|
| 12334 | id="x1-129000A.1"></a>Overview</h4>
|
|---|
| 12335 | <!--l. 7--><p class="noindent" >This document describes using Ogg logical and physical transport streams to encapsulate Vorbis
|
|---|
| 12336 | compressed audio packet data into file form.
|
|---|
| 12337 | <!--l. 11--><p class="noindent" >The <a
|
|---|
| 12338 | href="#x1-20001">section 1</a>, “<a
|
|---|
| 12339 | href="#x1-20001">Introduction and Description<!--tex4ht:ref: vorbis:spec:intro --></a>” provides an overview of the construction of Vorbis
|
|---|
| 12340 | audio packets.
|
|---|
| 12341 | <!--l. 14--><p class="noindent" >The <a
|
|---|
| 12342 | href="oggstream.html" >Ogg bitstream overview</a> and <a
|
|---|
| 12343 | href="framing.html" >Ogg logical bitstream and framing spec</a> provide detailed
|
|---|
| 12344 | descriptions of Ogg transport streams. This specification document assumes a working
|
|---|
| 12345 | knowledge of the concepts covered in these named backround documents. Please read them
|
|---|
| 12346 | first.
|
|---|
| 12347 | <!--l. 21--><p class="noindent" >
|
|---|
| 12348 | <h5 class="subsubsectionHead"><span class="titlemark">A.1.1. </span> <a
|
|---|
| 12349 | id="x1-130000A.1.1"></a>Restrictions</h5>
|
|---|
| 12350 | <!--l. 23--><p class="noindent" >The Ogg/Vorbis I specification currently dictates that Ogg/Vorbis streams use Ogg transport
|
|---|
| 12351 | streams in degenerate, unmultiplexed form only. That is:
|
|---|
| 12352 | <ul class="itemize1">
|
|---|
| 12353 | <li class="itemize">A meta-headerless Ogg file encapsulates the Vorbis I packets
|
|---|
| 12354 | </li>
|
|---|
| 12355 | <li class="itemize">The Ogg stream may be chained, i.e., contain multiple, contigous logical streams
|
|---|
| 12356 | (links).
|
|---|
| 12357 | </li>
|
|---|
| 12358 | <li class="itemize">The Ogg stream must be unmultiplexed (only one stream, a Vorbis audio stream,
|
|---|
| 12359 | per link)
|
|---|
| 12360 | </li></ul>
|
|---|
| 12361 |
|
|---|
| 12362 |
|
|---|
| 12363 |
|
|---|
| 12364 | <!--l. 40--><p class="noindent" >This is not to say that it is not currently possible to multiplex Vorbis with other media
|
|---|
| 12365 | types into a multi-stream Ogg file. At the time this document was written, Ogg was
|
|---|
| 12366 | becoming a popular container for low-bitrate movies consisting of DivX video and Vorbis
|
|---|
| 12367 | audio. However, a ’Vorbis I audio file’ is taken to imply Vorbis audio existing alone
|
|---|
| 12368 | within a degenerate Ogg stream. A compliant ’Vorbis audio player’ is not required to
|
|---|
| 12369 | implement Ogg support beyond the specific support of Vorbis within a degenrate Ogg
|
|---|
| 12370 | stream (naturally, application authors are encouraged to support full multiplexed Ogg
|
|---|
| 12371 | handling).
|
|---|
| 12372 | <!--l. 54--><p class="noindent" >
|
|---|
| 12373 | <h5 class="subsubsectionHead"><span class="titlemark">A.1.2. </span> <a
|
|---|
| 12374 | id="x1-131000A.1.2"></a>MIME type</h5>
|
|---|
| 12375 | <!--l. 56--><p class="noindent" >The MIME type of Ogg files depend on the context. Specifically, complex multimedia and
|
|---|
| 12376 | applications should use <span
|
|---|
| 12377 | class="cmtt-12">application/ogg</span>, while visual media should use <span
|
|---|
| 12378 | class="cmtt-12">video/ogg</span>, and audio
|
|---|
| 12379 | <span
|
|---|
| 12380 | class="cmtt-12">audio/ogg</span>. Vorbis data encapsulated in Ogg may appear in any of those types. RTP
|
|---|
| 12381 | encapsulated Vorbis should use <span
|
|---|
| 12382 | class="cmtt-12">audio/vorbis </span>+ <span
|
|---|
| 12383 | class="cmtt-12">audio/vorbis-config</span>.
|
|---|
| 12384 | <!--l. 64--><p class="noindent" >
|
|---|
| 12385 | <h4 class="subsectionHead"><span class="titlemark">A.2. </span> <a
|
|---|
| 12386 | id="x1-132000A.2"></a>Encapsulation</h4>
|
|---|
| 12387 | <!--l. 66--><p class="noindent" >Ogg encapsulation of a Vorbis packet stream is straightforward.
|
|---|
| 12388 | <ul class="itemize1">
|
|---|
| 12389 | <li class="itemize">The first Vorbis packet (the identification header), which uniquely identifies a stream
|
|---|
| 12390 | as Vorbis audio, is placed alone in the first page of the logical Ogg stream. This
|
|---|
| 12391 | results in a first Ogg page of exactly 58 bytes at the very beginning of the logical
|
|---|
| 12392 | stream.
|
|---|
| 12393 | </li>
|
|---|
| 12394 | <li class="itemize">This first page is marked ’beginning of stream’ in the page flags.
|
|---|
| 12395 | </li>
|
|---|
| 12396 | <li class="itemize">The second and third vorbis packets (comment and setup headers) may span one or
|
|---|
| 12397 | more pages beginning on the second page of the logical stream. However many pages
|
|---|
| 12398 | they span, the third header packet finishes the page on which it ends. The next (first
|
|---|
| 12399 | audio) packet must begin on a fresh page.
|
|---|
| 12400 |
|
|---|
| 12401 |
|
|---|
| 12402 |
|
|---|
| 12403 | </li>
|
|---|
| 12404 | <li class="itemize">The granule position of these first pages containing only headers is zero.
|
|---|
| 12405 | </li>
|
|---|
| 12406 | <li class="itemize">The first audio packet of the logical stream begins a fresh Ogg page.
|
|---|
| 12407 | </li>
|
|---|
| 12408 | <li class="itemize">Packets are placed into ogg pages in order until the end of stream.
|
|---|
| 12409 | </li>
|
|---|
| 12410 | <li class="itemize">The last page is marked ’end of stream’ in the page flags.
|
|---|
| 12411 | </li>
|
|---|
| 12412 | <li class="itemize">Vorbis packets may span page boundaries.
|
|---|
| 12413 | </li>
|
|---|
| 12414 | <li class="itemize">The granule position of pages containing Vorbis audio is in units of PCM audio
|
|---|
| 12415 | samples (per channel; a stereo stream’s granule position does not increment at twice
|
|---|
| 12416 | the speed of a mono stream).
|
|---|
| 12417 | </li>
|
|---|
| 12418 | <li class="itemize">The granule position of a page represents the end PCM sample position of the last
|
|---|
| 12419 | packet <span
|
|---|
| 12420 | class="cmti-12">completed </span>on that page. The ’last PCM sample’ is the last complete sample
|
|---|
| 12421 | returned by decode, not an internal sample awaiting lapping with a subsequent block.
|
|---|
| 12422 | A page that is entirely spanned by a single packet (that completes on a subsequent
|
|---|
| 12423 | page) has no granule position, and the granule position is set to ’-1’.
|
|---|
| 12424 | <!--l. 125--><p class="noindent" >Note that the last decoded (fully lapped) PCM sample from a packet is not
|
|---|
| 12425 | necessarily the middle sample from that block. If, eg, the current Vorbis packet
|
|---|
| 12426 | encodes a ”long block” and the next Vorbis packet encodes a ”short block”, the last
|
|---|
| 12427 | decodable sample from the current packet be at position (3*long_block_length/4) -
|
|---|
| 12428 | (short_block_length/4).
|
|---|
| 12429 | </li>
|
|---|
| 12430 | <li class="itemize">The granule (PCM) position of the first page need not indicate that the stream
|
|---|
| 12431 | started at position zero. Although the granule position belongs to the last completed
|
|---|
| 12432 | packet on the page and a valid granule position must be positive, by inference it may
|
|---|
| 12433 | indicate that the PCM position of the beginning of audio is positive or negative.
|
|---|
| 12434 | <ul class="itemize2">
|
|---|
| 12435 | <li class="itemize">A positive starting value simply indicates that this stream begins at some
|
|---|
| 12436 | positive time offset, potentially within a larger program. This is a common case
|
|---|
| 12437 | when connecting to the middle of broadcast stream.
|
|---|
| 12438 | </li>
|
|---|
| 12439 | <li class="itemize">A negative value indicates that output samples preceeding time zero should be
|
|---|
| 12440 |
|
|---|
| 12441 |
|
|---|
| 12442 |
|
|---|
| 12443 | discarded during decoding; this technique is used to allow sample-granularity
|
|---|
| 12444 | editing of the stream start time of already-encoded Vorbis streams. The number
|
|---|
| 12445 | of samples to be discarded must not exceed the overlap-add span of the first two
|
|---|
| 12446 | audio packets.
|
|---|
| 12447 | </li></ul>
|
|---|
| 12448 | <!--l. 160--><p class="noindent" >In both of these cases in which the initial audio PCM starting offset is nonzero, the
|
|---|
| 12449 | second finished audio packet must flush the page on which it appears and the
|
|---|
| 12450 | third packet begin a fresh page. This allows the decoder to always be able to
|
|---|
| 12451 | perform PCM position adjustments before needing to return any PCM data from
|
|---|
| 12452 | synthesis, resulting in correct positioning information without any aditional seeking
|
|---|
| 12453 | logic.
|
|---|
| 12454 | <!--l. 169--><p class="noindent" ><span class="likesubparagraphHead"><a
|
|---|
| 12455 | id="x1-133000A.2"></a><span
|
|---|
| 12456 | class="cmbx-12">Note:</span></span> Failure to do so should, at worst, cause a decoder implementation to return
|
|---|
| 12457 | incorrect positioning information for seeking operations at the very beginning of the
|
|---|
| 12458 | stream.
|
|---|
| 12459 | </li>
|
|---|
| 12460 | <li class="itemize">A granule position on the final page in a stream that indicates less audio data than the
|
|---|
| 12461 | final packet would normally return is used to end the stream on other than even frame
|
|---|
| 12462 | boundaries. The difference between the actual available data returned and the
|
|---|
| 12463 | declared amount indicates how many trailing samples to discard from the decoding
|
|---|
| 12464 | process.
|
|---|
| 12465 | </li></ul>
|
|---|
| 12466 |
|
|---|
| 12467 |
|
|---|
| 12468 |
|
|---|
| 12469 | <h3 class="sectionHead"><span class="titlemark">B. </span> <a
|
|---|
| 12470 | id="x1-134000B"></a>Vorbis encapsulation in RTP</h3>
|
|---|
| 12471 | <!--l. 7--><p class="noindent" >Please consult RFC 5215 <span
|
|---|
| 12472 | class="cmti-12">“RTP Payload Format for Vorbis Encoded Audio” </span>for description of
|
|---|
| 12473 | how to embed Vorbis audio in an RTP stream.
|
|---|
| 12474 |
|
|---|
| 12475 |
|
|---|
| 12476 |
|
|---|
| 12477 |
|
|---|
| 12478 |
|
|---|
| 12479 |
|
|---|
| 12480 | <h3 class="likesectionHead"><a
|
|---|
| 12481 | id="x1-135000B"></a>Colophon</h3>
|
|---|
| 12482 | <!--l. 5--><p class="noindent" ><img
|
|---|
| 12483 | src="fish_xiph_org.png" alt="PIC"
|
|---|
| 12484 | >
|
|---|
| 12485 | <!--l. 8--><p class="noindent" >Ogg is a <a
|
|---|
| 12486 | href="https://xiph.org/" >Xiph.Org Foundation</a> effort to protect essential tenets of Internet multimedia from
|
|---|
| 12487 | corporate hostage-taking; Open Source is the net’s greatest tool to keep everyone honest. See
|
|---|
| 12488 | <a
|
|---|
| 12489 | href="https://xiph.org/about/" >About the Xiph.Org Foundation</a> for details.
|
|---|
| 12490 | <!--l. 15--><p class="noindent" >Ogg Vorbis is the first Ogg audio CODEC. Anyone may freely use and distribute the Ogg and
|
|---|
| 12491 | Vorbis specification, whether in a private, public or corporate capacity. However, the Xiph.Org
|
|---|
| 12492 | Foundation and the Ogg project (xiph.org) reserve the right to set the Ogg Vorbis specification
|
|---|
| 12493 | and certify specification compliance.
|
|---|
| 12494 | <!--l. 21--><p class="noindent" >Xiph.Org’s Vorbis software CODEC implementation is distributed under a BSD-like license. This
|
|---|
| 12495 | does not restrict third parties from distributing independent implementations of Vorbis software
|
|---|
| 12496 | under other licenses.
|
|---|
| 12497 | <!--l. 26--><p class="noindent" >Ogg, Vorbis, Xiph.Org Foundation and their logos are trademarks (tm) of the <a
|
|---|
| 12498 | href="https://xiph.org/" >Xiph.Org
|
|---|
| 12499 | Foundation</a>. These pages are copyright (C) 1994-2015 Xiph.Org Foundation. All rights
|
|---|
| 12500 | reserved.
|
|---|
| 12501 | <!--l. 31--><p class="noindent" >This document is set using <span class="LATEX">L<span class="A">A</span><span class="TEX">T<span
|
|---|
| 12502 | class="E">E</span>X</span></span>.
|
|---|
| 12503 |
|
|---|
| 12504 |
|
|---|
| 12505 |
|
|---|
| 12506 | <h3 class="likesectionHead"><a
|
|---|
| 12507 | id="x1-136000B"></a>References</h3>
|
|---|
| 12508 | <!--l. 132--><p class="noindent" >
|
|---|
| 12509 | <div class="thebibliography">
|
|---|
| 12510 | <p class="bibitem" ><span class="biblabel">
|
|---|
| 12511 | [1]<span class="bibsp">   </span></span><a
|
|---|
| 12512 | id="XSporer/Brandenburg/Edler"></a>T. Sporer, K. Brandenburg and
|
|---|
| 12513 | B. Edler, The use of multirate filter banks for coding of high quality digital audio,
|
|---|
| 12514 | <a
|
|---|
| 12515 | href="https://media.taricorp.net/eusipco_corrected.pdf" class="url" ><span
|
|---|
| 12516 | class="cmtt-12">https://media.taricorp.net/eusipco_corrected.pdf</span></a>.
|
|---|
| 12517 | </p>
|
|---|
| 12518 | </div>
|
|---|
| 12519 |
|
|---|
| 12520 | </body></html>
|
|---|
| 12521 |
|
|---|
| 12522 |
|
|---|
| 12523 |
|
|---|
| 12524 |
|
|---|
