[Ffmpeg-devel] [PATCH]changed rle encoder consecutive pixels count

[Michael Niedermayer]

Hi

On Wed, Apr 04, 2007 at 08:20:55PM +0800, Xiaohui Sun wrote:
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> Michael Niedermayer ????:
> > Hi
> > 
> > On Wed, Apr 04, 2007 at 07:11:32PM +0800, Xiaohui Sun wrote:
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> >> Hi,
> >>   changed the max consecutive pixels count from 128 to 127. For some
> >> image encoder , it accepts up to 0x7F(127) consecutive pixels.
> > 
> > iam ok with the change, allthough it would be interresting to see
> > what effect it has on compression (that is the standard test images like
> > lena, foreman video, ...)
> 
> Imho, in some rare situation, this would degrade the compression rate
> about 1 percent.

a image with run of 128x0, 128x1, 128x0, ... will have 40-50% worse
compression depending on how smart the rle encoder is ...

question is more what is with actual images, i think the loss is negligible
0.1% or so but it would be insterresting to know the actual numbers that is
not guessing but testing

[...]

-- 
Michael     GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB

The educated differ from the uneducated as much as the living from the
dead. -- Aristotle 
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