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