1 This demonstrates the use of PNG_USER_CONFIG and pngusr.h 2 3 The makefile builds a minimal write-only encoder with embedded libpng 4 and zlib. 5 6 Specify the location of the zlib source (1.2.1 or later) as ZLIBSRC 7 on the make command line. 8 9 If you prefer to use the shared libraries, go to contrib/pngminus 10 and build the pnm2png application there. 11