| 1 | # read.dfa
|
|---|
| 2 | # Build time configuration of libpng
|
|---|
| 3 | #
|
|---|
| 4 | # Author: John Bowler
|
|---|
| 5 | # Copyright: (c) John Bowler, 2013
|
|---|
| 6 | # Usage rights:
|
|---|
| 7 | # To the extent possible under law, the author has waived all copyright and
|
|---|
| 8 | # related or neighboring rights to this work. This work is published from:
|
|---|
| 9 | # United States.
|
|---|
| 10 | #
|
|---|
| 11 | # Build libpng with basic read support. This enables the lowest level libpng
|
|---|
| 12 | # read API - the one where the calling code has to use a loop to read each row.
|
|---|
| 13 | # At present this is the API used by most programs.
|
|---|
| 14 | #
|
|---|
| 15 | # Support is enabled only for those chunks and transformations that are
|
|---|
| 16 | # typically required - others can be added easily.
|
|---|
| 17 | #
|
|---|
| 18 |
|
|---|
| 19 | everything = off
|
|---|
| 20 |
|
|---|
| 21 | # The sequential read code is enabled here; the progressive code can be used
|
|---|
| 22 | # instead but there is no point enabling both.
|
|---|
| 23 |
|
|---|
| 24 | option SEQUENTIAL_READ on
|
|---|
| 25 |
|
|---|
| 26 | # Likewise it is pointless enabling both fixed and floating point APIs. Choose
|
|---|
| 27 | # one or the other for both the API and the internal math.
|
|---|
| 28 |
|
|---|
| 29 | #Fixed point:
|
|---|
| 30 | #option FIXED_POINT on
|
|---|
| 31 | #option FLOATING_ARITHMETIC off
|
|---|
| 32 |
|
|---|
| 33 | #Floating point:
|
|---|
| 34 | option FLOATING_POINT on
|
|---|
| 35 | option FLOATING_ARITHMETIC on
|
|---|
| 36 |
|
|---|
| 37 | # Basic error handling, IO and user memory support. The latter allows the
|
|---|
| 38 | # application program to provide its own implementations of 'malloc' and 'free'.
|
|---|
| 39 | option SETJMP on
|
|---|
| 40 | option STDIO on
|
|---|
| 41 | option USER_MEM on
|
|---|
| 42 |
|
|---|
| 43 | # To read the full set of PNG images correctly interlace, transparency and
|
|---|
| 44 | # 16-bit support is required. The application can implement interlace itself,
|
|---|
| 45 | # but very few do and it's no longer possible to disable it when READ is
|
|---|
| 46 | # enabled.
|
|---|
| 47 | option READ_tRNS on
|
|---|
| 48 | option READ_16BIT on
|
|---|
| 49 |
|
|---|
| 50 | # Everything else is application dependent. This file assumes the app handles
|
|---|
| 51 | # all the native PNG bit layouts, so it doesn't need any of layout change
|
|---|
| 52 | # transforms, but needs libpng to perform gamma correction. It doesn't do any
|
|---|
| 53 | # colorspace stuff and ignores the 'significant bit' information.
|
|---|
| 54 | #
|
|---|
| 55 | # If your app always expands the image to a limited set of bit layouts you
|
|---|
| 56 | # probably want to consider using the simplified API instead of the low level
|
|---|
| 57 | # one - see png.h and s_read.dfa.
|
|---|
| 58 | option READ_GAMMA on
|
|---|
