PNG

The PNG abbreviation stands for Portable Network Graphics, and is an image format supported by all recent Graal clients. It is an open format, its libraries are open source, and it is generally considered superior to GIFs in almost every way (although PNGs do not support animation). However, Graal2 presently imposes odd restrictions on which PNGs it will display; specifically, the image must be a 256-color, non-interlaced, optimized octree image with either no or single color transparency - neither alpha blending and 32-bit color are supported.