How to convert a 24 Bit PNG to 3 Bit PNG using Floyd–Steinberg dithering?

Question

How to convert a 24 Bit PNG to 3 Bit PNG using Floyd–Steinberg dithering? java.awt.image.BufferedImage should be used to get and set RGB values.

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Answer 1

source code needs the missing method "diff" in the static class C3. otherwise, it doesn't compile or work.

here's the missing diff method:

public int diff(C3 o) {
    int Rdiff = o.r - this.r;
    int Gdiff = o.g - this.g;
    int Bdiff = o.b - this.b;
    int distanceSquared = Rdiff*Rdiff + Gdiff*Gdiff + Bdiff*Bdiff;
    return distanceSquared;
}