Re: MMX speedup for Floyd Steinberg error diffusion

I figured it out...

I do all my processing in the form of 4 signed WORDS in the MMX
registers, and finally I use packuswb which takes the 4 and packs them
into unsigned bytes with saturation.

The code works exactly as my C++ version did and I have a speedup of
more than 2X !! :)

Excellent!

Thanks all

.

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