Quantization to 16 colors with different error dithering

NeuQuant 16 colors + Floyd-Steinberg
RMSE 33.796
NeuQuant 16 colors + Jarvis
RMSE 32.010
NeuQuant 16 colors + Stucki
RMSE 32.193
NeuQuant 16 colors + Sierra 3
RMSE 32.169
NeuQuant 16 colors + Sierra 2
RMSE 32.689
NeuQuant 16 colors + Sierra 42A
RMSE 34.146
NeuQuant 16 colors + Riemersma
RMSE 33.763
SColorQ 16 colors
RMSE 41.719