Scolorq dithering?

[NM64]

I came across a dithering algorithm that appears to be even higher quality than Floyd Steinberg. The only problem is that it seems to be quite slow, but the speed tests were done with a 2.8GHz Pentium 4, so now-a-days with our quad-core extremes and stuff, speed should be less of an issue.

Site with source & binary downloads, info, and test examples:
http://www.moonflare.com/code/scolorq/

EDIT: I've just realized through some of my own testing, in the test comparisons, the images under the category "photoshop" seem to be a bit worse than XnView's Floyd Steinberg, though the color-association choice issue is still present - one of the key advantages of Scolorg. (see the pool table example image)

Also, since XnView doesn't even allow color depths of less than 16, some of the main advantages of this are lost. (minor edit: though it's available in grey-scale, so there's a use) Though as someone that makes custom windows bootscreens, an awesome-quality dither'er @ 16 colors would be great

EDIT 2: It looks like Scolorq is one of 3 dithering algorithms based on the idea of color quantization, and each seems to give pretty similar results, but I can't test for direct comparison. (though I think Scolorq touts itself as the best-quality color-quantization dithering algorithm)

The others, with links, are PNGNQ and NeuQuant

EDIT 3: You can see another image quality comparison on wikipedia as well: http://en.wikipedia.org/wiki/Dithering# ... algorithms

EDIT 4: Found some more Scolorq test comparisons: http://bisqwit.iki.fi/jutut/colorquant/

[Troken]

Very interesting samples, it looks great.

[XnTriq]

Very interesting indeed! Thanks for the hint, nintendomaniac64.

[XnTriq]

You can find a free photoshop plugin which includes scolorq and is compatible with XNView in
http://www.ximagic.com