[FFmpeg-devel] [PATCH] avcodec/cbs_av1: infer ref_order_hint when not coded in the bitstream

[Mark Thompson]

On 31/10/2020 14:40, James Almer wrote:
> Signed-off-by: James Almer <jamrial at gmail.com>
> ---
>   libavcodec/cbs_av1_syntax_template.c | 10 ++++++++--
>   1 file changed, 8 insertions(+), 2 deletions(-)
> 
> diff --git a/libavcodec/cbs_av1_syntax_template.c b/libavcodec/cbs_av1_syntax_template.c
> index f351b1de24..dc3d8d1048 100644
> --- a/libavcodec/cbs_av1_syntax_template.c
> +++ b/libavcodec/cbs_av1_syntax_template.c
> @@ -1490,13 +1490,19 @@ static int FUNC(uncompressed_header)(CodedBitstreamContext *ctx, RWContext *rw,
>           fb(8, refresh_frame_flags);
>   
>       if (!frame_is_intra || current->refresh_frame_flags != all_frames) {
> -        if (current->error_resilient_mode && seq->enable_order_hint) {
> +        if (seq->enable_order_hint) {
>               for (i = 0; i < AV1_NUM_REF_FRAMES; i++) {
> -                fbs(order_hint_bits, ref_order_hint[i], 1, i);
> +                if (current->error_resilient_mode)
> +                    fbs(order_hint_bits, ref_order_hint[i], 1, i);
> +                else
> +                    infer(ref_order_hint[i], priv->ref[i].order_hint);
>                   if (current->ref_order_hint[i] != priv->ref[i].order_hint)
>                       priv->ref[i].valid = 0;
>               }
>           }
> +    } else if (seq->enable_order_hint) {
> +        for (i = 0; i < AV1_NUM_REF_FRAMES; i++)
> +            infer(ref_order_hint[i], priv->ref[i].order_hint);

Is filling these on a key frame meaningful in any way?  The slots need not be valid at all, such as at the first frame in a stream.

>       }
>   
>       if (current->frame_type == AV1_FRAME_KEY ||
> 

Probably good anyway.

Thanks,

- Mark