[FFmpeg-devel] [PATCH 4/6] avcodec/h264: keep track of which frames used gray references

[Vittorio Giovara]

On Sun, Nov 19, 2023 at 7:11 PM Michael Niedermayer <michael at niedermayer.cc>
wrote:

> On Tue, Nov 14, 2023 at 07:46:16PM +0100, Michael Niedermayer wrote:
> > On Tue, Nov 14, 2023 at 06:32:19PM +0100, Hendrik Leppkes wrote:
> > > On Tue, Nov 14, 2023 at 6:21 PM Michael Niedermayer
> > > <michael at niedermayer.cc> wrote:
> > > >
> > > > Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>
> > > > ---
> > > >  libavcodec/h264_picture.c |  1 +
> > > >  libavcodec/h264_slice.c   | 19 ++++++++++++++++++-
> > > >  libavcodec/h264dec.c      |  1 +
> > > >  libavcodec/h264dec.h      |  4 ++++
> > > >  4 files changed, 24 insertions(+), 1 deletion(-)
> > > >
> > > > diff --git a/libavcodec/h264_picture.c b/libavcodec/h264_picture.c
> > > > index 691c61eea23..3234141dbd6 100644
> > > > --- a/libavcodec/h264_picture.c
> > > > +++ b/libavcodec/h264_picture.c
> > > > @@ -96,6 +96,7 @@ static void h264_copy_picture_params(H264Picture
> *dst, const H264Picture *src)
> > > >      dst->field_picture = src->field_picture;
> > > >      dst->reference     = src->reference;
> > > >      dst->recovered     = src->recovered;
> > > > +    dst->gray          = src->gray;
> > > >      dst->invalid_gap   = src->invalid_gap;
> > > >      dst->sei_recovery_frame_cnt = src->sei_recovery_frame_cnt;
> > > >      dst->mb_width      = src->mb_width;
> > > > diff --git a/libavcodec/h264_slice.c b/libavcodec/h264_slice.c
> > > > index 4861a2cabba..2c4ab89dae1 100644
> > > > --- a/libavcodec/h264_slice.c
> > > > +++ b/libavcodec/h264_slice.c
> > > > @@ -457,6 +457,7 @@ int ff_h264_update_thread_context(AVCodecContext
> *dst,
> > > >      h->poc.prev_frame_num        = h->poc.frame_num;
> > > >
> > > >      h->recovery_frame        = h1->recovery_frame;
> > > > +    h->non_gray              = h1->non_gray;
> > > >
> > > >      return err;
> > > >  }
> > > > @@ -1544,11 +1545,14 @@ static int h264_field_start(H264Context *h,
> const H264SliceContext *sl,
> > > >                  if (ret < 0)
> > > >                      return ret;
> > > >                  h->short_ref[0]->poc = prev->poc + 2U;
> > > > +                h->short_ref[0]->gray = prev->gray;
> > > >                  ff_thread_report_progress(&h->short_ref[0]->tf,
> INT_MAX, 0);
> > > >                  if (h->short_ref[0]->field_picture)
> > > >                      ff_thread_report_progress(&h->short_ref[0]->tf,
> INT_MAX, 1);
> > > > -            } else if (!h->frame_recovered && !h->avctx->hwaccel)
> > > > +            } else if (!h->frame_recovered && !h->avctx->hwaccel) {
> > > >                  color_frame(h->short_ref[0]->f, c);
> > > > +                h->short_ref[0]->gray = 1;
> > > > +            }
> > >
> > > While we can't color invalid frames for hwaccels easily, the flag
> > > should perhaps still be applied, as they are equally invalid.
> >
> > ok
>
> will apply with this changed
>
> >
> >
> > > Thinking about this, maybe the name should be less the color we
> > > happened to use for it, and more like "placeholder" or "invalid" or
> > > anything like that?
> >
> > "invalid" is a quite generic term that covers more than this case.
> > and iam not sure if "placeholder" is really good description of them.
> > I picked "gray" because i had no better idea and they are gray
>
> if someone comes up with a better name, we can rename it
> but gray is kind of fitting
>

Sorry, what exactly are h264 gray frames?

Could you add some documentation to the new field in H264Picture too?
-- 
Vittorio