On: Dither stabilisation

[mrob]

The dithered highlight on the sphere looks odd because it was calculated in a non-linear colorspace. You can get better looking results by converting to a linear colorspace, dithering, then converting back to sRGB. Eg, in ImageMagick, using the same 8x8 matrix:

convert Dither2-Exp_crop_resize.png -colorspace RGB -ordered-dither o8x8,2 -colorspace sRGB Dither2-Exp_dithered.png

Result: https://imgur.com/a/81bNg

[klodolph → mrob]

Although in this case, the conversion back to sRGB is just the identity…

[amluto → klodolph]

True. But if the dither mask was computed without taking into account sRGB's nonlinearity (which I assume it was), then the algorithm will have the same incorrect output.