Quote:
Originally Posted by cretindesalpes
From the previous pictures, I magnified and amplified several zones in order to show the differences more clearly:
  
Still the same order:
Original / Filtered
GradFun2db / GradFun3
Dither / Dither+SmoothGrad
One can see that both GradFun function perform poorly near the edges. This is because they are based on massive box filtering and have to stop as soon as the box overlaps an area of a different color. Ideally, these function would use a large bilateral filter, but this would be really overkill and much much slower. |
Every single one there except gradfun looks utterly terrible. Why? Because they use ordered dither. Use error diffusion, for the sake of your eyes.