[FFmpeg-devel] [PATCH] avcodec/vvcdec: fix seeking for open GOP

[Nuo Mi]

On Sat, Feb 3, 2024 at 6:35 PM Nuo Mi <nuomi2021 at gmail.com> wrote:

> how to reproduce:
> wget https://media.xiph.org/video/derf/y4m/students_cif.y4m
> vvencapp --input students_cif.y4m --preset faster --output students.266
> MP4Box -add students.266:fps=30000/1001:par=12:11 -new students.mp4
> ffplay students.mp4

Applied, thanks James for the review

> ---
>  libavcodec/vvc/vvc_refs.c | 6 ++++++
>  libavcodec/vvc/vvc_refs.h | 1 +
>  libavcodec/vvc/vvcdec.c   | 6 ++++++
>  3 files changed, 13 insertions(+)
>
> diff --git a/libavcodec/vvc/vvc_refs.c b/libavcodec/vvc/vvc_refs.c
> index bf503e429e..e1895d1cca 100644
> --- a/libavcodec/vvc/vvc_refs.c
> +++ b/libavcodec/vvc/vvc_refs.c
> @@ -80,6 +80,12 @@ void ff_vvc_clear_refs(VVCFrameContext *fc)
>              VVC_FRAME_FLAG_SHORT_REF | VVC_FRAME_FLAG_LONG_REF);
>  }
>
> +void ff_vvc_flush_dpb(VVCFrameContext *fc)
> +{
> +    for (int i = 0; i < FF_ARRAY_ELEMS(fc->DPB); i++)
> +        ff_vvc_unref_frame(fc, &fc->DPB[i], ~0);
> +}
> +
>  static void free_progress(FFRefStructOpaque unused, void *obj)
>  {
>      FrameProgress *p = (FrameProgress *)obj;
> diff --git a/libavcodec/vvc/vvc_refs.h b/libavcodec/vvc/vvc_refs.h
> index cd3b5f5632..eba4422fb4 100644
> --- a/libavcodec/vvc/vvc_refs.h
> +++ b/libavcodec/vvc/vvc_refs.h
> @@ -33,6 +33,7 @@ int ff_vvc_frame_rpl(VVCContext *s, VVCFrameContext *fc,
> SliceContext *sc);
>  int ff_vvc_slice_rpl(VVCContext *s, VVCFrameContext *fc, SliceContext
> *sc);
>  void ff_vvc_unref_frame(VVCFrameContext *fc, VVCFrame *frame, int flags);
>  void ff_vvc_clear_refs(VVCFrameContext *fc);
> +void ff_vvc_flush_dpb(VVCFrameContext *fc);
>
>  typedef enum VVCProgress {
>      VVC_PROGRESS_MV,
> diff --git a/libavcodec/vvc/vvcdec.c b/libavcodec/vvc/vvcdec.c
> index 83ee472ce6..1a050600eb 100644
> --- a/libavcodec/vvc/vvcdec.c
> +++ b/libavcodec/vvc/vvcdec.c
> @@ -922,9 +922,15 @@ static av_cold void vvc_decode_flush(AVCodecContext
> *avctx)
>  {
>      VVCContext *s  = avctx->priv_data;
>      int got_output = 0;
> +    VVCFrameContext *last;
>
>      while (s->nb_delayed)
>          wait_delayed_frame(s, NULL, &got_output);
> +
> +    last = get_frame_context(s, s->fcs, s->nb_frames - 1);
> +    ff_vvc_flush_dpb(last);
> +
> +    s->eos = 1;
>  }
>
>  static av_cold int vvc_decode_free(AVCodecContext *avctx)
> --
> 2.25.1
>
>