[FFmpeg-devel] [PATCH 2/2] swscale: Add swscale and fate support for AYUV

[Carl Eugen Hoyos]

Am Mi., 28. Aug. 2019 um 09:52 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 14:58
> > To: FFmpeg development discussions and patches <ffmpeg-
> > devel at ffmpeg.org>
> > Subject: Re: [FFmpeg-devel] [PATCH 2/2] swscale: Add swscale and fate
> > support for AYUV
> >
> >
> >
> > > Am 28.08.2019 um 08:22 schrieb Linjie Fu <linjie.fu at intel.com>:
> > >
> > > Add swscale support for AYUV and make it more robust.
> >
> > The path that converts from AYUV to planar YUV(A) seems to be missing the
> > handling of alpha values.
>
> Alpha channel information in AYUV are treated in the same way for RGBA/BGRA and
> is reusing rgbaToA_c to handle the alpha values.
>
> When converting AYUV to YUA/YUVA, two methods are acceptable:
> - For YUV, just cut the alpha and discard the transparency
> - For format which also contains an alpha channel(YUV444P), copy the
> alpha information seems good.

But since the input does not contain (valid) alpha, this does not apply.

Carl Eugen