Colorsquash

a small dog laying on a concrete floor in an industrial building
24bit rgb
the same image in 256 color. there are some visual differences, but the two images look very similar
256 color indexed
Platform Size
Windows x64 463K
Linux x64 460K
Linux aarch64 463K
MacOS x64 424K
MacOS ARM 413K
squash v0.3.0

colorsquash is a tool for squishing your image into only 256 distinct colours, allowing it to fit in a GIF or indexed PNG. It tries to do this with as little change as possible.