May 26, 2018
Optimizer for PNG files
pngcrush reads in a PNG image, and writes it out again, with the optimum filter_type and zlib_level. It uses brute force trying filter_type none, and libpng adaptive filtering, with compression levels 3 and 9. It does the most time-consuming method last in case it turns out to be the best. Optionally, it can remove unwanted chunks or add gAMA and sRGB chunks.