[FFmpeg-devel] [PATCH 3/5] avcodec/proresenc_kostya: do not write into alpha reserved bitfields

[Michael Niedermayer]

On Wed, Dec 13, 2023 at 12:13:36AM +0100, Michael Niedermayer wrote:
> On Mon, Dec 11, 2023 at 08:06:53PM +0100, Clément Bœsch wrote:
> > This byte represents 4 reserved bits followed by 4 alpha_channel_type bits.
> > 
> > alpha_channel_type currently has 3 differents defined values: 0 (no
> > alpha), 1 (8b alpha), and 2 (16b alpha), all the other values are
> > reserved. This part is correctly written (alpha_bits>>3 does the correct
> > thing), but the 4 initial bits are reserved.
> > ---
> >  libavcodec/proresenc_kostya.c | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> This breaks fate (not just changing the value but actually breaking it)

This is about the next patch "avcodec/proresenc_anatoliy: do not write into alpha reserved bitfields"
I used a too short search string for the subject i replied to ...
(so issue is real but its the next patch)


> 
> --- ./tests/ref/vsynth/vsynth1-prores_444_int	2023-12-02 00:46:44.277042842 +0100
> +++ tests/data/fate/vsynth1-prores_444_int	2023-12-13 00:11:22.144115839 +0100
> @@ -1,4 +1,2 @@
> -1d5e484fa8ca08781ef2ed8428963d12 *tests/data/fate/vsynth1-prores_444_int.mov
> +d75a2ba07d0642340d040edab6cbb3bb *tests/data/fate/vsynth1-prores_444_int.mov
>  9940947 tests/data/fate/vsynth1-prores_444_int.mov
> -732ceeb6887524e0aee98762fe50578b *tests/data/fate/vsynth1-prores_444_int.out.rawvideo
> -stddev:    2.83 PSNR: 39.08 MAXDIFF:   45 bytes:  7603200/  7603200

[...]

-- 
Michael     GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB

Some people wanted to paint the bikeshed green, some blue and some pink.
People argued and fought, when they finally agreed, only rust was left.
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 195 bytes
Desc: not available
URL: <https://ffmpeg.org/pipermail/ffmpeg-devel/attachments/20231213/b62579ee/attachment.sig>