[FFmpeg-user] A question on H.264 High 4:4:4 Predictive decode support on NVIDIA Pascal hardware via nvdec

[Dennis Mungai]

On Thu, 9 May 2019 at 03:06, Philip Langdale <philipl at overt.org> wrote:

> On Thu, 9 May 2019 02:53:01 +0300
> Dennis Mungai <dmngaie at gmail.com> wrote:
>
> > >
> > > The GPU matrix published by NVIDIA only indicates support for HEVC
> > > @ 4:4:4 :
> > > https://developer.nvidia.com/video-encode-decode-gpu-support-matrix.
> > > That page indicates support for H.264 4:4:4 in NVENC (as from
> > > GM107+) but information on decode capability on the same is absent.
> > >
> > > According to the commit:
> > >
> https://git.ffmpeg.org/gitweb/ffmpeg.git/commit/83c7ac2e47efd96927127c1c385cdbb5fb53cb02
> > >
> > > Only two codecs can handle 4:4:4: HEVC and MJPEG.
> > > Would this imply that support for H.264 @ 4:4:4 is either
> > > unsupported (in hardware, as implied above) or  omitted in FFmpeg?
> > > Please clarify.
> > >
> > > Thanks for your time,
> > >
> > > Dennis.
>
> No hardware supports decoding of 4:4:4 h.264 content, and I'm sure
> nvidia will never add it, given that h.264 is now old news. They
> support decoding 4:2:0 content that was encoded with the high444p
> profile, for whatever that's worth, but that's why the profile is
> listed as supported.
>
> --phil
>

Thanks for the clarification.