I got really bored so I wrote a simple dithering tool in Kotlin. It is surprising how little loss you get when reducing an image to 8 colors. Source code: https://gist.github.com/Frederikam/115a15450bec82720d3bb5a70b5ceefd
This particular algorithm is called Floyd-Steinberg dithering https://en.wikipedia.org/wiki/Floyd%E2%80%93Steinberg_dithering
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