billd@celerity.UUCP (Bill Davidson) (05/24/89)
Well, I tried my idea for modifying the median cut method by cutting
at a point in which each half of the array represented roughly the
same number of pixels in the original image. I got varying results.
Some images were *slightly* degraded. You could only tell in detailed
spots with rare colors. This is rare in the images I have. Several
images showed no discernable affect over just using a standard median
cut and doing a weighted average for each box. A few images were
vastly improved. Ray-tracing images which involved shiny reflective
spheres lost almost all banding! I really had to look close to see
any at all. The background had been badly banded before and it's banding
disappeared. I expected a slight improvement and I got a vast
improvement. So, what's the verdict? Did I re-invent the wheel
(or at least a spoke :-) or what? If somebody doesn't say something
first, I'll probably try to figure the mean quantization error for
the entire image with of these variants and try to figure best/worst
case scenarios.
Bill Davidson ...!{ucsd,sdsu,fpssun,cogen,chip,photon}!celerity!billd