Top 5 png-compression open source projects

Lossy PNG compressor — pngquant command based on libimagequant library

Crunch is a tool for lossy PNG image file optimization. It combines selective bit depth, color type, and color palette reduction with zopfli DEFLATE compression algorithm encoding using the pngquant and zopflipng PNG optimization tools. This approach leads to a significant file size gain relative to lossless approaches at the expense of a relatively modest decrease in image quality (see example images below).

Simple image optimizer for JPEG, PNG and GIF images on Linux, MacOS and FreeBSD.

A Python Wrapper of Pngquant

Lossy compression of PNG images