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Libima update

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Subject: Libima update
From: mihai.moise5@gmail.com (Mihai Moise)
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by: Mihai Moise - Mon, 23 Jan 2023 05:13 UTC

I just got a new computer from Newegg. It makes my old one look like junk. With 8 cores instead of 2, a brute force optimization takes 1 day instead of 4.

I have noticed that even though a cubic predictor has a higher PSNR, a quadratic predictor looks better for lossy compression because it smudges edges less. Smudges are more annoying than other artifacts. Even better results can be achieved by detecting which blocks have an edge and using more bits.

For this image:
https://www.pngegg.com/en/png-wvrud

here are the file sizes:

asymmetric cubic 4099820
symmetric cubic 4035623
symmetric quadratic 3966858

I use coffee to give me energy to program.

For small images, if you blink you missed it, because Libima is fast, fast, fast.

--
Get stewed.
Books are a load of crap.

Breadth-first search is the bulldozer of science. -- Randy Goebel

devel / comp.compression / Libima update