[FFmpeg-devel] [PATCH] avfilter/vf_scale: reset color matrix in case of identity & non-RGB

[Jan Ekström]

On Sat, Aug 28, 2021 at 12:03 AM Michael Niedermayer
<michael at niedermayer.cc> wrote:
>
> On Fri, Aug 27, 2021 at 01:02:31AM +0300, Jan Ekström wrote:
> > On Sun, Aug 22, 2021 at 11:55 PM Jan Ekström <jeebjp at gmail.com> wrote:
> > >
> > > Fixes passing through mismatching metadata from the input side
> > > when RGB input (from f.ex. H.264 or HEVC) gets converted to YCbCr.
> > >
> > > Fixes #9132
> > > ---
> > >  libavfilter/vf_scale.c | 9 +++++++++
> > >  1 file changed, 9 insertions(+)
> > >
> > > diff --git a/libavfilter/vf_scale.c b/libavfilter/vf_scale.c
> > > index ce39217515..7ca833bbb1 100644
> > > --- a/libavfilter/vf_scale.c
> > > +++ b/libavfilter/vf_scale.c
> > > @@ -738,6 +738,15 @@ scale:
> > >      out->width  = outlink->w;
> > >      out->height = outlink->h;
> > >
> > > +    // Sanity check: If we've got the RGB/XYZ (identity) matrix configured, and
> > > +    //               the output is no longer RGB, unset the matrix.
> > > +    //               In theory this should be in swscale itself as the AVFrame
> > > +    //               based API gets in, so that not every swscale API user has
> > > +    //               to go through duplicating such sanity checks.
> > > +    if (out->colorspace == AVCOL_SPC_RGB &&
> > > +        !(av_pix_fmt_desc_get(out->format)->flags & AV_PIX_FMT_FLAG_RGB))
> > > +        out->colorspace = AVCOL_SPC_UNSPECIFIED;
> > > +
> > >      if (scale->output_is_pal)
> > >          avpriv_set_systematic_pal2((uint32_t*)out->data[1], outlink->format == AV_PIX_FMT_PAL8 ? AV_PIX_FMT_BGR8 : outlink->format);
> > >
> > > --
> > > 2.31.1
> > >
> >
> > Unless there are objections, I will pull this in soon. I will also
> > attempt to see if I can add a programmatic FATE test for all of the
> > allowed configurations of vf_scale, to see if there are any other
> > clear-cut cases where not all metadata from the input AVFrame can be
> > passed on as-is and has to be reset.
>
> no objections
>
> thx

Thanks, applied as 9dd410c80416197188337e3b7e1600be41d2ea64 .

Jan