In creating the ASE Palette Converter, I had to reverse-engineer the contents of proprietary Adobe ASE Adobe Swatch Exchange files. As with anything reverse-engineered, the following file format spec is only my best-guess of the actual, official Adobe ASE file specification. For instance, a field which I indicate is a four-byte field might be perhaps just a two-byte integer with two bytes of unused space.

Starting with the CS2 product line, Adobe Systems introduced a cross-program swatch format called Adobe Swatch Exchange format or ASE for short. The purpose of the swatch file format is to allow different programs to use and exchange palettes.

Kuler the online palette app generates ASE palette files as well, but the palette format purely proprietary, and is not published. Nevertheless, with some help from others who did some reverse-engineering of the format and a bit of my own studying of various binary files generated by Kuler and other Adobe apps, I've gained a very good understanding of the ASE file format.