The version is 1.8.13, Pngcrush is a easy-to-use, command line optimizer for PNG files. pngcrush and other tools for manipulating PNG (Portable Network Graphics) and MNG (Multiple-image Network Graphics) files. usage: 1. pngcrush [options] infile.png outfile.png 2. pngcrush -e ext [other options] files.png ... 3. pngcrush -d dir...