Quantization to 256 colors of Lena with None/Riemersma error dithering.

The image is scaled down to 400x400

256 Colors	256 Colors + Riemersma
Uniform (3,3,2)
RMSE 26.980	RMSE 39.141
Popularity (5 bits)
RMSE 11.106	RMSE 18.728
Median Cut (8 bits)
RMSE 5.953	RMSE 8.600
Octree (8 bits 2-pass)
RMSE 6.448	RMSE 9.083
Xiaolin Wu v2
RMSE 5.395	RMSE 7.747
Dennis Lee v3 (5 bits)
RMSE 5.316	RMSE 7.766
Binary Split
RMSE 5.365	RMSE 7.754
Lloyd (K-Means)
RMSE 5.177	RMSE 7.682
NeuQuant (200 cycles)
RMSE 5.227	RMSE 7.515
SColorQ
NA