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 19everything = 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 24option 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: 34option FLOATING_POINT on 35option 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'. 39option SETJMP on 40option STDIO on 41option 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. 47option READ_tRNS on 48option 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. 58option READ_GAMMA on 59