[FFmpeg-devel] [PATCH] avcodec/ffv1: Store slices*planes with the minimum bits needed after remap

[Michael Niedermayer]

On Thu, Apr 03, 2025 at 02:07:36AM +0200, Michael Niedermayer wrote:
> Hi Jerome
> 
> On Wed, Apr 02, 2025 at 11:31:53PM +0200, Jerome Martinez wrote:
> > Le 02/04/2025 à 23:13, Michael Niedermayer a écrit :
> > > [...]
> > > 
> > > This improves compression as wrap around can be cheaper to reach a
> > > value.
> > 
> > 
> > There is an issue in FFV1 version <=3 with RCT, bit depth of resulting
> > luminance plane was 1 more than needed (RCT adds 1 bit to chrominance but
> > not to luminance, but with current spec all planes have 1 additional bit),
> > preventing in practice the wrap around for luminance, do I understand well
> > that the remap would mitigate such issue?
> 
> yes, in fact with version 4 that issue is fixed with this patch without remap too

correction, with the v2 i will post in a moment. This one
was missing some hunks

[...]

-- 
Michael     GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB

Breaking DRM is a little like attempting to break through a door even
though the window is wide open and the only thing in the house is a bunch
of things you dont want and which you would get tomorrow for free anyway
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