This isn't a medical image format either but included here as a replacement for the patent burdened Gif format. The format does require the libpng library being installed on your system. Although it will read most files, internally we only work with a 256 indexed palette. And to simplify things further, no exotic features like alpha channels or interlacing is supported. Contrary to GIF, this is a single image format. So writing a volume to PNG will result in separate files for each image slice. Just to know, we do include patient/scan info in a comment chunck.