[FFmpeg-devel] [PATCH v1 1/2] lavu/pixfmt: add new pixel format a2r10g10b10/a2b10g10r10

[Song, Ruiling]

> -----Original Message-----
> From: ffmpeg-devel <ffmpeg-devel-bounces at ffmpeg.org> On Behalf Of
> Carl Eugen Hoyos
> Sent: Friday, September 27, 2019 7:47 PM
> To: FFmpeg development discussions and patches <ffmpeg-
> devel at ffmpeg.org>
> Subject: Re: [FFmpeg-devel] [PATCH v1 1/2] lavu/pixfmt: add new pixel
> format a2r10g10b10/a2b10g10r10
> 
> Am Fr., 27. Sept. 2019 um 11:02 Uhr schrieb Sun, Xinpeng
> <xinpeng.sun at intel.com>:
> 
> > > > Add two 10 bit RGBA pixel format for hardware color space conversion
> > > > support in VAAPI and QSV:
> > > >
> > > > 2:10:10:10 10 bit: A2R10G10B10
> > > > 2:10:10:10 10 bit: A2B10G10R10
> > >
> > > Without more explanation, this patch is not ok.
> 
> > The main reasons for adding these two format are as follows:
> > 1. For most HDR monitors, A2R10G10B10 is used for display format for
> > rendering. So this format is important to do 10bit RGB rendering support
> > in ffmpeg.
> 
> For which operating systems (and video drivers) is this true?
Here:
https://docs.microsoft.com/en-us/windows/win32/direct3d9/d3dformat
and here:
https://docs.microsoft.com/en-us/windows/win32/directshow/uncompressed-rgb-video-subtypes

It is defined in Windows APIs. so I guess these are widely used 10bit RGB format on Windows?

> And which video players will profit from this filter?
> 
> > 2. HW VPP can do both p010->a2r10g10b10 and a2r10g10b10->p010
> > with this patch, which can provide support for hw encode pipeline
> > using a2r10g10b10 as input.
> 
> But if the pipeline (that you control, no?) would support GBRP10, not
> only one (very) specific use case would be supported but all thinkable
> use cases, or do I misunderstand?
AFAIK, Intel GPU does not support planar RGB10 currently. May be we can add some format conversion between GBRP10 and the new added formats in swscale? (I am not if this could help the thinkable use cases you mean.)
And could you share your thought why supporting planar RGB10 is important? Thanks!

Ruiling
> 
> Afaict, the fact that FFmpeg cannot deal at all with HDR is the most
> pressing issue we have atm. I believe that only solving this problem
> for one specific use case is not the ideal solution.
> 
> Carl Eugen
> _______________________________________________
> ffmpeg-devel mailing list
> ffmpeg-devel at ffmpeg.org
> https://ffmpeg.org/mailman/listinfo/ffmpeg-devel
> 
> To unsubscribe, visit link above, or email
> ffmpeg-devel-request at ffmpeg.org with subject "unsubscribe".