URL: http://libpng.org/
Version: 1.5.4
License: zlib/libpng
License File: LICENSE

Description:
libpng is the official PNG reference library. It supports almost all
PNG features, is extensible, and has been extensively tested for over
15 years.

Local Modifications:
1. Modified pnglibconf.h to disable reading of PLTE chunks when they
   are optional.
