angif layered
angif fork with transparency layers (proof of concept implementation)
...Workflow: import truecolor image to GIMP, export 24RAW from GIMP, feeding to rawtogif.exe e.g. "rawtogif.exe 1024 768 sunflower.raw"
output a uncompressed (no LZW compression) GIF, needs to be feed to gifsicle for reasonable size.