[FFmpeg-devel] [PATCH 1/3] avcodec/dxva2_hevc: add support for parsing HEVC Range Extension data

[Hendrik Leppkes]

On Sun, Mar 15, 2020 at 8:12 AM Steve Lhomme <robux4 at ycbcr.xyz> wrote:
> > Where is this struct specified? I don't see it in the latest released
> > Windows SDK.
>
> It is not. It is reversed engineered from the existing structure and wild guessing based on the HEVC Range Extension specs. The bits/fields are in the same order as the specs. Then I tested some GUIDs that output non 4:2:0 pixel formats on an Intel GPU that is known to decoder HEVC Range Extension.
>
> Apparently NVIDIA doesn't provide DXVA GUIDs that output non 4:2:0 pixel formats on GPUs that supposedly decode HEVC 444 (likley nvdec only). AMD doesn't have such GPUs AFAIK.
>
> So for now it's Intel only.

That seems very hackish for something thats otherwise cleanly based on
official specifications only.  Maybe try to get them to release specs
for this instead?

- Hendrik