libpng-legacy12 (old PNG library for compatibility with old software) PNG (Portable Network Graphics) is an extensible file format for the lossless, portable, well-compressed storage of raster images. This build provides libpng12.so, occasionally needed for running older binary-only software. It can safely be installed without conflicting with Slackware's own libpng (which is version 1.6). Rather than compiling libpng-1.2, this build simply repackages the latest official binary from Slackware 14.1's patches/. If you're looking for libpng-1.4, it's already provided in Slackware's aaa_libraries package (as libpng14.so).