[D3D11VA] Request to enable DXVA HEVC YUV444 support

[AndrewKeYanzhe]

mpv Information

Other Information

- Windows version: Windows 11 25H2
- GPU model, driver and version: RTX 2080
- Source of mpv:
- Latest known working version: NIL
- Issue started after the following happened:

Reproduction Steps

Play a HEVC YUV 444 video (10 bit for example). Notice that it is software decoded.

Expected Behavior

Hardware decoding works.

Actual Behavior

Hardware decoding doesn't work.

As @kasper93 explained in #18172 (comment) :

444 HEVC is supported in official documentation now https://learn.microsoft.com/en-us/windows-hardware/drivers/ddi/dxva/ns-dxva-dxva_picparams_hevc_rangeext

I could implement this official extension, but I don't have hardware to test this on, so I won't.

I am willing to try and implement the fix, allowing MPV to utilise D3D11VA's HEVC YUV444 hardware decoder. I would like to get the HEVC 444 8b, 10b and 12b variants all working.

I would greatly appreciate if any MPV developer can provide some guidance, including which files I should look at/edit.

If any developer wants to help and implement the fix but lacks the hardware to test it on, I am more than happy to help run the tests. I have an RTX 2080.

Log File

output_sanitized.txt

Sample Files

No response

I carefully read all instruction and confirm that I did the following:

• I tested and confirmed that the issue exists with the latest release version or newer.
• I provided all required information including system and mpv version.
• I produced the log file with the exact same set of files, parameters, and conditions used in "Reproduction Steps", with the addition of --log-file=output.txt.
• I produced the log file while the behaviors described in "Actual Behavior" were actively observed.
• I attached the full, untruncated log file.
• I attached the backtrace in the case of a crash.

[Andarwinux]

FYI, https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/20334

[AndrewKeYanzhe]

Thanks for pointing to that FFmpeg PR.

So, MPV's D3D11VA hardware decoding paths typically go through FFmpeg API calls?

Also thank you @kasper93 for further reviewing that FFmpeg PR.

Does anyone know if there is any mpv PR integrating this FFmpeg PR? Maybe I can try out the patch on my local compilation. Thanks!

[kasper93]

So, MPV's D3D11VA hardware decoding paths typically go through FFmpeg API calls?

Yes.

Does anyone know if there is any mpv PR integrating this FFmpeg PR? Maybe I can try out the patch on my local compilation. Thanks!

You can try using it. If it works, mpv will use it.

[AndrewKeYanzhe]

Does mpv need any code changes? Or is it that when ffmpeg supports DXVA hevc 444, the recompiled mpv will automatically support it too?

[kasper93]

Does mpv need any code changes? Or is it that when ffmpeg supports DXVA hevc 444, the recompiled mpv will automatically support it too?

I've added support for most of the formats #18176, I have not checked against this ffmpeg pr, but either way, you can test with -copy which will always work.