[FFmpeg-devel] [PATCH 01/20] avcodec/hevc_sei: Use proper type for NALU type

[Soft Works]

> -----Original Message-----
> From: Andreas Rheinhardt <andreas.rheinhardt at outlook.com>
> Sent: Wednesday, November 23, 2022 4:20 AM
> To: Soft Works <softworkz at hotmail.com>; FFmpeg development
> discussions and patches <ffmpeg-devel at ffmpeg.org>
> Subject: Re: [FFmpeg-devel] [PATCH 01/20] avcodec/hevc_sei: Use
> proper type for NALU type
> 
> Soft Works:
> >
> >
> >> -----Original Message-----
> >> From: ffmpeg-devel <ffmpeg-devel-bounces at ffmpeg.org> On Behalf Of
> >> Andreas Rheinhardt
> >> Sent: Sunday, July 3, 2022 12:21 AM
> >> To: ffmpeg-devel at ffmpeg.org
> >> Cc: Andreas Rheinhardt <andreas.rheinhardt at outlook.com>
> >> Subject: [FFmpeg-devel] [PATCH 01/20] avcodec/hevc_sei: Use proper
> >> type for NALU type
> >>
> >> Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt at outlook.com>
> >> ---
> >
> > Nice! That's helpful for the QSV SEI parsing. The one missing bit
> > is the HDR data (AVMasteringDisplayMetadata and
> AVContentLightMetadata)
> > assignment which still seems to remain in hevcdec. Would it make
> sense
> > for factor this out as well?
> >
> 
> While the H.264 and HEVC syntax and semantics for these coincide, the
> HEVC implementation of it is not completely spec-compliant with
> respect
> to its persistency: The persistence ends when the coded video
> sequence
> ends and if the new coded video sequence does not have these SEIs,
> then
> we would need to attach an AVMasteringDisplayMetadata and/or
> AVContentLightMetadata just to cancel the earlier values. I just
> don't
> want to enter this and this includes not extending it to H.264.

Just to clarify - by "factoring out" AVMasteringDisplayMetadata
and AVContentLightMetadata, I didn't mean in a way that it gets
unified to handle H.264 and H.265. I just meant to move it into
a separate module, so that it can be used by qsvdec.c without needing
to link to the whole H.265 implementation.

sw