[FFmpeg-devel] [PATCH 0/3] vaapi: Add support for decoding 8bit 4:4:4 content

[Philip Langdale]

On Sat, 23 Jul 2022 11:53:12 -0700
Philip Langdale <philipl at overt.org> wrote:

> Recent Intel hardware is capable of decoding 8bit 4:4:4 HEVC and VP9,
> but it uses a packed format that Microsoft wants, and which we don't
> currently know about.
> 
> This patch series adds support for the AYUV format and declares
> support in VAAPI.
> 
> Mark has noted that due to there never being any actual Alpha produced
> by the hardware, we should use an XYUV format. I've not done so here
> because libva does declare an explicit XYUV format, which I assume we
> will see used in the future, and I didn't want to fudge the formats so
> that they lose the nominal distinction. But I'm happy to change that
> if desired.
> 
> Philip Langdale (3):
>   lavu/pixfmt: Add packed 4:4:4 format
>   lavu/hwcontext_vaapi: Map the AYUV format
>   lavc/vaapi: Declare support for decoding 8bit 4:4:4 content
> 
>  Changelog                        |  1 +
>  doc/APIchanges                   |  3 +++
>  libavcodec/hevcdec.c             |  3 +++
>  libavcodec/vaapi_decode.c        |  2 ++
>  libavcodec/version.h             |  2 +-
>  libavcodec/vp9.c                 |  5 +++++
>  libavutil/hwcontext_vaapi.c      |  1 +
>  libavutil/pixdesc.c              | 13 +++++++++++++
>  libavutil/pixfmt.h               |  2 ++
>  libavutil/version.h              |  4 ++--
>  tests/ref/fate/imgutils          |  1 +
>  tests/ref/fate/sws-pixdesc-query |  4 ++++
>  12 files changed, 38 insertions(+), 3 deletions(-)
> 

I will push this in the next few days if I don't get any comments or
objections. Hai Hao confirmed in IRC that the Intel driver does
explicitly set the alpha value to 0xFF so it is correct to treat it
as an alpha value rather than undefined.

Thanks,

--phil