[FFmpeg-devel] [PATCH 1/2] lavu/pixfmt: add AYUV pixel format

[Hendrik Leppkes]

On Thu, Aug 29, 2019 at 1:47 PM Carl Eugen Hoyos <ceffmpeg at gmail.com> wrote:
>
>
>
> Am 29.08.2019 um 03:34 schrieb Fu, Linjie <linjie.fu at intel.com>:
>
> >> -----Original Message-----
> >> From: ffmpeg-devel [mailto:ffmpeg-devel-bounces at ffmpeg.org] On Behalf
> >> Of Carl Eugen Hoyos
> >> Sent: Thursday, August 29, 2019 05:17
> >> To: FFmpeg development discussions and patches <ffmpeg-
> >> devel at ffmpeg.org>
> >> Subject: Re: [FFmpeg-devel] [PATCH 1/2] lavu/pixfmt: add AYUV pixel format
> >>
> >>>> Am Mi., 28. Aug. 2019 um 09:34 Uhr schrieb Fu, Linjie <linjie.fu at intel.com>:
> >>>>
> >>>> -----Original Message-----
> >>>> From: ffmpeg-devel [mailto:ffmpeg-devel-bounces at ffmpeg.org] On
> >> Behalf
> >>>> Of Carl Eugen Hoyos
> >>>> Sent: Wednesday, August 28, 2019 14:51
> >>>> To: FFmpeg development discussions and patches <ffmpeg-
> >>>> devel at ffmpeg.org>
> >>>> Subject: Re: [FFmpeg-devel] [PATCH 1/2] lavu/pixfmt: add AYUV pixel
> >> format
> >>>>
> >>>>
> >>>>
> >>>>> Am 28.08.2019 um 08:22 schrieb Linjie Fu <linjie.fu at intel.com>:
> >>>>>
> >>>>> Add support for packed 4:4:4 pixel format AYUV.
> >>>>>
> >>>>> It is the format that VAAPI/QSV uses when coping with 4:4:4
> >>>>> surfaces.
> >>>>
> >>>>> Alpha channel will be set to default value for HEVC REXT
> >>>>> hw decode.
> >>>>
> >>>> What is the „default value“?
> >>>
> >>> Default zero. (and it should be 255 for display)
> >>
> >> If this is not a bug in the driver, there is no alpha channel that can be used.
> >> Rename it to 0YUV and remove the alpha usage.
> >
> > From the pixel format level, adding AYUV format is for a more fundamental/common usage.
>
> Yes, but the new pixel format will only be accepted if it is needed for hardware compatibility.
> If the hardware only supports 0YUV, it cannot be used to argue in favour of a new AYUV format.
>

AYUV is a standard format used on Windows and documented by Microsoft
as the recommended 4:4:4 8-bit format for all purposes. Its hardly a
niche format. Its perfectly appropriate to support it.

- Hendrik