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

[Fu, Linjie]

> -----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.
It is valid no matter the alpha data is 0 or 255 or specific value to indicate the transparency.

And the hardware decode result is an AYUV format with fixed alpha values, so it should still be
an AYUV format IMHO.

- linjie