Re: MMX speedup for Floyd Steinberg error diffusion

Terje Mathisen  <spamtrap@[EMAIL PROTECTED]
> writes:
> rep_movsd wrote:
>>> Phil, you're absolutely right, and that's why "doing it right" is even
>>> harder than you're showing here:
>>
>> There is this color quantizer/ditherer program called scolorq which
>> uses some highly advanced techniques with floating point precision. I
>
> I.e. convert each pixel to fp, then to a linear color space, do all
> error diffusion in this format, then use the final palette colors?
>
>> tried that out and it took an astoni****ng amount of time for a single
>> frame ( I let it run for 3 minutes before giving up in disgust ).
>> Turns out it has 5 deep nested loops. Some site online shows pretty
>> impressive results for reduction to 16 color images. Perhaps the
>
> You might be able to do 16-color images by making the color diffusion
> are significantly larger: Keep luminance info as close as possible,
> but allow color to be spread across a larger area?

You might be able to just do some kind of octree algorithm. 
You could even hard-code the partitions.

(Octree's also possible in 256-colours too, of course. You can 
even create a slightly optimised palate by using 2 p***** and
crudely bin-counting on the 3 axes.)

Phil
-- 
Dear aunt, let's set so double the killer delete select all.
-- Microsoft voice recognition live demonstration