| 1 | /** @file
|
|---|
| 2 | * Image resampling code, used for snapshot thumbnails.
|
|---|
| 3 | */
|
|---|
| 4 |
|
|---|
| 5 | /*
|
|---|
| 6 | * Copyright (C) 2009 Oracle Corporation
|
|---|
| 7 | *
|
|---|
| 8 | * This file is part of VirtualBox Open Source Edition (OSE), as
|
|---|
| 9 | * available from http://www.virtualbox.org. This file is free software;
|
|---|
| 10 | * you can redistribute it and/or modify it under the terms of the GNU
|
|---|
| 11 | * General Public License (GPL) as published by the Free Software
|
|---|
| 12 | * Foundation, in version 2 as it comes in the "COPYING" file of the
|
|---|
| 13 | * VirtualBox OSE distribution. VirtualBox OSE is distributed in the
|
|---|
| 14 | * hope that it will be useful, but WITHOUT ANY WARRANTY of any kind.
|
|---|
| 15 | */
|
|---|
| 16 |
|
|---|
| 17 | /*
|
|---|
| 18 | * Based on gdImageCopyResampled from libgd.
|
|---|
| 19 | * Original copyright notice follows:
|
|---|
| 20 |
|
|---|
| 21 | Portions copyright 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007
|
|---|
| 22 | Pierre-Alain Joye (pierre@libgd.org).
|
|---|
| 23 |
|
|---|
| 24 | Permission has been granted to copy, distribute and modify gd in
|
|---|
| 25 | any context without fee, including a commercial application,
|
|---|
| 26 | provided that this notice is present in user-accessible supporting
|
|---|
| 27 | documentation.
|
|---|
| 28 |
|
|---|
| 29 | This does not affect your ownership of the derived work itself, and
|
|---|
| 30 | the intent is to assure proper credit for the authors of gd, not to
|
|---|
| 31 | interfere with your productive use of gd. If you have questions,
|
|---|
| 32 | ask. "Derived works" includes all programs that utilize the
|
|---|
| 33 | library. Credit must be given in user-accessible documentation.
|
|---|
| 34 |
|
|---|
| 35 | This software is provided "AS IS." The copyright holders disclaim
|
|---|
| 36 | all warranties, either express or implied, including but not
|
|---|
| 37 | limited to implied warranties of merchantability and fitness for a
|
|---|
| 38 | particular purpose, with respect to this code and accompanying
|
|---|
| 39 | documentation.
|
|---|
| 40 | */
|
|---|
| 41 |
|
|---|
| 42 | /*
|
|---|
| 43 | *
|
|---|
| 44 | * @todo Simplify: Offsets of images are 0,0 => no dstX, dstY, srcX, srcY;
|
|---|
| 45 | * Screenshot has no alpha channel => no processing of alpha byte.
|
|---|
| 46 | */
|
|---|
| 47 |
|
|---|
| 48 | #include <iprt/types.h>
|
|---|
| 49 |
|
|---|
| 50 | /* 2.0.10: cast instead of floor() yields 35% performance improvement.
|
|---|
| 51 | Thanks to John Buckman. */
|
|---|
| 52 |
|
|---|
| 53 | #define floor2(exp) ((long) exp)
|
|---|
| 54 | /*#define floor2(exp) floor(exp)*/
|
|---|
| 55 |
|
|---|
| 56 | typedef uint8_t *gdImagePtr;
|
|---|
| 57 |
|
|---|
| 58 | DECLINLINE(int) gdImageGetTrueColorPixel (gdImagePtr im, int x, int y, int w)
|
|---|
| 59 | {
|
|---|
| 60 | return *(int32_t *)(im + y * w * 4 + x * 4);
|
|---|
| 61 | }
|
|---|
| 62 |
|
|---|
| 63 | DECLINLINE(void) gdImageSetPixel (gdImagePtr im, int x, int y, int color, int w)
|
|---|
| 64 | {
|
|---|
| 65 | *(int32_t *)(im + y * w * 4 + x * 4) = color;
|
|---|
| 66 | }
|
|---|
| 67 |
|
|---|
| 68 | #define gdAlphaMax 127
|
|---|
| 69 | #define gdAlphaOpaque 0
|
|---|
| 70 | #define gdAlphaTransparent 127
|
|---|
| 71 | #define gdRedMax 255
|
|---|
| 72 | #define gdGreenMax 255
|
|---|
| 73 | #define gdBlueMax 255
|
|---|
| 74 | #define gdTrueColorGetAlpha(c) (((c) & 0x7F000000) >> 24)
|
|---|
| 75 | #define gdTrueColorGetRed(c) (((c) & 0xFF0000) >> 16)
|
|---|
| 76 | #define gdTrueColorGetGreen(c) (((c) & 0x00FF00) >> 8)
|
|---|
| 77 | #define gdTrueColorGetBlue(c) ((c) & 0x0000FF)
|
|---|
| 78 | #define gdTrueColorAlpha(r, g, b, a) (((a) << 24) + \
|
|---|
| 79 | ((r) << 16) + \
|
|---|
| 80 | ((g) << 8) + \
|
|---|
| 81 | (b))
|
|---|
| 82 |
|
|---|
| 83 | void gdImageCopyResampled (uint8_t *dst,
|
|---|
| 84 | uint8_t *src,
|
|---|
| 85 | int dstX, int dstY,
|
|---|
| 86 | int srcX, int srcY,
|
|---|
| 87 | int dstW, int dstH, int srcW, int srcH)
|
|---|
| 88 | {
|
|---|
| 89 | int x, y;
|
|---|
| 90 | double sy1, sy2, sx1, sx2;
|
|---|
| 91 | for (y = dstY; (y < dstY + dstH); y++)
|
|---|
| 92 | {
|
|---|
| 93 | sy1 = ((double) y - (double) dstY) * (double) srcH / (double) dstH;
|
|---|
| 94 | sy2 = ((double) (y + 1) - (double) dstY) * (double) srcH /
|
|---|
| 95 | (double) dstH;
|
|---|
| 96 | for (x = dstX; (x < dstX + dstW); x++)
|
|---|
| 97 | {
|
|---|
| 98 | double sx, sy;
|
|---|
| 99 | double spixels = 0;
|
|---|
| 100 | double red = 0.0, green = 0.0, blue = 0.0, alpha = 0.0;
|
|---|
| 101 | sx1 = ((double) x - (double) dstX) * (double) srcW / dstW;
|
|---|
| 102 | sx2 = ((double) (x + 1) - (double) dstX) * (double) srcW / dstW;
|
|---|
| 103 | sy = sy1;
|
|---|
| 104 | do
|
|---|
| 105 | {
|
|---|
| 106 | double yportion;
|
|---|
| 107 | if (floor2 (sy) == floor2 (sy1))
|
|---|
| 108 | {
|
|---|
| 109 | yportion = 1.0 - (sy - floor2 (sy));
|
|---|
| 110 | if (yportion > sy2 - sy1)
|
|---|
| 111 | {
|
|---|
| 112 | yportion = sy2 - sy1;
|
|---|
| 113 | }
|
|---|
| 114 | sy = floor2 (sy);
|
|---|
| 115 | }
|
|---|
| 116 | else if (sy == floor2 (sy2))
|
|---|
| 117 | {
|
|---|
| 118 | yportion = sy2 - floor2 (sy2);
|
|---|
| 119 | }
|
|---|
| 120 | else
|
|---|
| 121 | {
|
|---|
| 122 | yportion = 1.0;
|
|---|
| 123 | }
|
|---|
| 124 | sx = sx1;
|
|---|
| 125 | do
|
|---|
| 126 | {
|
|---|
| 127 | double xportion;
|
|---|
| 128 | double pcontribution;
|
|---|
| 129 | int p;
|
|---|
| 130 | if (floor2 (sx) == floor2 (sx1))
|
|---|
| 131 | {
|
|---|
| 132 | xportion = 1.0 - (sx - floor2 (sx));
|
|---|
| 133 | if (xportion > sx2 - sx1)
|
|---|
| 134 | {
|
|---|
| 135 | xportion = sx2 - sx1;
|
|---|
| 136 | }
|
|---|
| 137 | sx = floor2 (sx);
|
|---|
| 138 | }
|
|---|
| 139 | else if (sx == floor2 (sx2))
|
|---|
| 140 | {
|
|---|
| 141 | xportion = sx2 - floor2 (sx2);
|
|---|
| 142 | }
|
|---|
| 143 | else
|
|---|
| 144 | {
|
|---|
| 145 | xportion = 1.0;
|
|---|
| 146 | }
|
|---|
| 147 | pcontribution = xportion * yportion;
|
|---|
| 148 | /* 2.08: previously srcX and srcY were ignored.
|
|---|
| 149 | Andrew Pattison */
|
|---|
| 150 | p = gdImageGetTrueColorPixel (src,
|
|---|
| 151 | (int) sx + srcX,
|
|---|
| 152 | (int) sy + srcY, srcW);
|
|---|
| 153 | red += gdTrueColorGetRed (p) * pcontribution;
|
|---|
| 154 | green += gdTrueColorGetGreen (p) * pcontribution;
|
|---|
| 155 | blue += gdTrueColorGetBlue (p) * pcontribution;
|
|---|
| 156 | alpha += gdTrueColorGetAlpha (p) * pcontribution;
|
|---|
| 157 | spixels += xportion * yportion;
|
|---|
| 158 | sx += 1.0;
|
|---|
| 159 | }
|
|---|
| 160 | while (sx < sx2);
|
|---|
| 161 | sy += 1.0;
|
|---|
| 162 | }
|
|---|
| 163 | while (sy < sy2);
|
|---|
| 164 | if (spixels != 0.0)
|
|---|
| 165 | {
|
|---|
| 166 | red /= spixels;
|
|---|
| 167 | green /= spixels;
|
|---|
| 168 | blue /= spixels;
|
|---|
| 169 | alpha /= spixels;
|
|---|
| 170 | }
|
|---|
| 171 | /* Clamping to allow for rounding errors above */
|
|---|
| 172 | if (red > 255.0)
|
|---|
| 173 | {
|
|---|
| 174 | red = 255.0;
|
|---|
| 175 | }
|
|---|
| 176 | if (green > 255.0)
|
|---|
| 177 | {
|
|---|
| 178 | green = 255.0;
|
|---|
| 179 | }
|
|---|
| 180 | if (blue > 255.0)
|
|---|
| 181 | {
|
|---|
| 182 | blue = 255.0;
|
|---|
| 183 | }
|
|---|
| 184 | if (alpha > gdAlphaMax)
|
|---|
| 185 | {
|
|---|
| 186 | alpha = gdAlphaMax;
|
|---|
| 187 | }
|
|---|
| 188 | gdImageSetPixel (dst,
|
|---|
| 189 | x, y,
|
|---|
| 190 | gdTrueColorAlpha ((int) red,
|
|---|
| 191 | (int) green,
|
|---|
| 192 | (int) blue, (int) alpha), dstW);
|
|---|
| 193 | }
|
|---|
| 194 | }
|
|---|
| 195 | }
|
|---|
| 196 |
|
|---|
| 197 | /* Fast integer implementation for 32 bpp bitmap scaling.
|
|---|
| 198 | * Use fixed point values * 16.
|
|---|
| 199 | */
|
|---|
| 200 | typedef int32_t FIXEDPOINT;
|
|---|
| 201 | #define INT_TO_FIXEDPOINT(i) (FIXEDPOINT)((i) << 4)
|
|---|
| 202 | #define FIXEDPOINT_TO_INT(v) (int)((v) >> 4)
|
|---|
| 203 | #define FIXEDPOINT_FLOOR(v) ((v) & ~0xF)
|
|---|
| 204 | #define FIXEDPOINT_FRACTION(v) ((v) & 0xF)
|
|---|
| 205 |
|
|---|
| 206 | /* For 32 bit source only. */
|
|---|
| 207 | void BitmapScale32 (uint8_t *dst,
|
|---|
| 208 | int dstW, int dstH,
|
|---|
| 209 | const uint8_t *src,
|
|---|
| 210 | int iDeltaLine,
|
|---|
| 211 | int srcW, int srcH)
|
|---|
| 212 | {
|
|---|
| 213 | int x, y;
|
|---|
| 214 |
|
|---|
| 215 | for (y = 0; y < dstH; y++)
|
|---|
| 216 | {
|
|---|
| 217 | FIXEDPOINT sy1 = INT_TO_FIXEDPOINT(y * srcH) / dstH;
|
|---|
| 218 | FIXEDPOINT sy2 = INT_TO_FIXEDPOINT((y + 1) * srcH) / dstH;
|
|---|
| 219 |
|
|---|
| 220 | for (x = 0; x < dstW; x++)
|
|---|
| 221 | {
|
|---|
| 222 | FIXEDPOINT red = 0, green = 0, blue = 0;
|
|---|
| 223 |
|
|---|
| 224 | FIXEDPOINT sx1 = INT_TO_FIXEDPOINT(x * srcW) / dstW;
|
|---|
| 225 | FIXEDPOINT sx2 = INT_TO_FIXEDPOINT((x + 1) * srcW) / dstW;
|
|---|
| 226 |
|
|---|
| 227 | FIXEDPOINT spixels = (sx2 - sx1) * (sy2 - sy1);
|
|---|
| 228 |
|
|---|
| 229 | FIXEDPOINT sy = sy1;
|
|---|
| 230 |
|
|---|
| 231 | do
|
|---|
| 232 | {
|
|---|
| 233 | FIXEDPOINT yportion;
|
|---|
| 234 | if (FIXEDPOINT_FLOOR (sy) == FIXEDPOINT_FLOOR (sy1))
|
|---|
| 235 | {
|
|---|
| 236 | yportion = INT_TO_FIXEDPOINT(1) - FIXEDPOINT_FRACTION(sy);
|
|---|
| 237 | if (yportion > sy2 - sy1)
|
|---|
| 238 | {
|
|---|
| 239 | yportion = sy2 - sy1;
|
|---|
| 240 | }
|
|---|
| 241 | sy = FIXEDPOINT_FLOOR (sy);
|
|---|
| 242 | }
|
|---|
| 243 | else if (sy == FIXEDPOINT_FLOOR (sy2))
|
|---|
| 244 | {
|
|---|
| 245 | yportion = FIXEDPOINT_FRACTION(sy2);
|
|---|
| 246 | }
|
|---|
| 247 | else
|
|---|
| 248 | {
|
|---|
| 249 | yportion = INT_TO_FIXEDPOINT(1);
|
|---|
| 250 | }
|
|---|
| 251 |
|
|---|
| 252 | const uint8_t *pu8SrcLine = src + iDeltaLine * FIXEDPOINT_TO_INT(sy);
|
|---|
| 253 | FIXEDPOINT sx = sx1;
|
|---|
| 254 | do
|
|---|
| 255 | {
|
|---|
| 256 | FIXEDPOINT xportion;
|
|---|
| 257 | FIXEDPOINT pcontribution;
|
|---|
| 258 | int p;
|
|---|
| 259 | if (FIXEDPOINT_FLOOR (sx) == FIXEDPOINT_FLOOR (sx1))
|
|---|
| 260 | {
|
|---|
| 261 | xportion = INT_TO_FIXEDPOINT(1) - FIXEDPOINT_FRACTION(sx);
|
|---|
| 262 | if (xportion > sx2 - sx1)
|
|---|
| 263 | {
|
|---|
| 264 | xportion = sx2 - sx1;
|
|---|
| 265 | }
|
|---|
| 266 | pcontribution = xportion * yportion;
|
|---|
| 267 | sx = FIXEDPOINT_FLOOR (sx);
|
|---|
| 268 | }
|
|---|
| 269 | else if (sx == FIXEDPOINT_FLOOR (sx2))
|
|---|
| 270 | {
|
|---|
| 271 | xportion = FIXEDPOINT_FRACTION(sx2);
|
|---|
| 272 | pcontribution = xportion * yportion;
|
|---|
| 273 | }
|
|---|
| 274 | else
|
|---|
| 275 | {
|
|---|
| 276 | xportion = INT_TO_FIXEDPOINT(1);
|
|---|
| 277 | pcontribution = xportion * yportion;
|
|---|
| 278 | }
|
|---|
| 279 | /* Color depth specific code begin */
|
|---|
| 280 | p = *(uint32_t *)(pu8SrcLine + FIXEDPOINT_TO_INT(sx) * 4);
|
|---|
| 281 | /* Color depth specific code end */
|
|---|
| 282 | red += gdTrueColorGetRed (p) * pcontribution;
|
|---|
| 283 | green += gdTrueColorGetGreen (p) * pcontribution;
|
|---|
| 284 | blue += gdTrueColorGetBlue (p) * pcontribution;
|
|---|
| 285 |
|
|---|
| 286 | sx += INT_TO_FIXEDPOINT(1);
|
|---|
| 287 | } while (sx < sx2);
|
|---|
| 288 |
|
|---|
| 289 | sy += INT_TO_FIXEDPOINT(1);
|
|---|
| 290 | } while (sy < sy2);
|
|---|
| 291 |
|
|---|
| 292 | if (spixels != 0)
|
|---|
| 293 | {
|
|---|
| 294 | red /= spixels;
|
|---|
| 295 | green /= spixels;
|
|---|
| 296 | blue /= spixels;
|
|---|
| 297 | }
|
|---|
| 298 | /* Clamping to allow for rounding errors above */
|
|---|
| 299 | if (red > 255)
|
|---|
| 300 | {
|
|---|
| 301 | red = 255;
|
|---|
| 302 | }
|
|---|
| 303 | if (green > 255)
|
|---|
| 304 | {
|
|---|
| 305 | green = 255;
|
|---|
| 306 | }
|
|---|
| 307 | if (blue > 255)
|
|---|
| 308 | {
|
|---|
| 309 | blue = 255;
|
|---|
| 310 | }
|
|---|
| 311 | gdImageSetPixel (dst,
|
|---|
| 312 | x, y,
|
|---|
| 313 | ( ((int) red) << 16) + (((int) green) << 8) + ((int) blue),
|
|---|
| 314 | dstW);
|
|---|
| 315 | }
|
|---|
| 316 | }
|
|---|
| 317 | }
|
|---|
| 318 |
|
|---|
