The PyPNG module implements support for PNG images. It reads and writes PNG files with all allowable bit depths (1/2/4/8/16/24/32/48/64 bits per pixel) and colour combinations: greyscale (1/2/4/8/16 bit); RGB, RGBA, LA (greyscale with alpha) with 8/16 bits per channel; colour mapped images (1/2/4/8 bit). Adam7 interlacing is supported for reading and writing. A number of optional chunks can be specified (when writing) and understood (when reading): tRNS, bKGD, gAMA.

PyPNG is not a high level toolkit for image processing (like PIL) and does not aim at being a replacement or competitor. Its strength lies in fine-grained extensive support of PNG features. It can also read and write Netpbm PAM files, with a focus on its use as an intermediate format for implementing custom PNG processing.