Re: [FFmpeg-devel] [PATCH v3] avcodec/av1_vaapi: fixed a decoding corruption issue

["Wang, Fei W" <fei.w.wang-at-intel.com@ffmpeg.org>]

On Wed, 2022-11-02 at 15:35 -0400, Ruijing Dong wrote:
> In av1_spec.pdf page 38/669, there is a sentence below:
> 
> if ( frame_type == KEY_FRAME && show_frame ) {
>    for ( i = 0; i < NUM_REF_FRAMES; i++) {
>       RefValid[ i ] = 0
>       ......
>    }
>    ......
> }
> 
> This shows that the condition of invalidating current
> DPB frames should be the coming frame_type is KEY_FRAME plus
> show_frame is equal to 1. Otherwise, some of the frames
> in sequence after KEY_FRAME still refer to the reference frames
> before KEY_FRAME, and if these before KEY_FRAME reference
> frames were invalidated, these frames could not find their
> reference frames, and it could cause image corruption.
> 
> Mesa fix is in 
> https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/19386
> 
> Signed-off-by: Ruijing Dong <ruijing.dong@amd.com>
> ---
> update: re-organize commit message and title
> 
>  libavcodec/vaapi_av1.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/libavcodec/vaapi_av1.c b/libavcodec/vaapi_av1.c
> index 63374c31c9..d0339b2705 100644
> --- a/libavcodec/vaapi_av1.c
> +++ b/libavcodec/vaapi_av1.c
> @@ -274,7 +274,7 @@ static int vaapi_av1_start_frame(AVCodecContext
> *avctx,
>      };
> 
>      for (int i = 0; i < AV1_NUM_REF_FRAMES; i++) {
> -        if (pic_param.pic_info_fields.bits.frame_type ==
> AV1_FRAME_KEY)
> +        if (pic_param.pic_info_fields.bits.frame_type ==
> AV1_FRAME_KEY && frame_header->show_frame)

LGTM, Thanks.

Fei

>              pic_param.ref_frame_map[i] = VA_INVALID_ID;
>          else
>              pic_param.ref_frame_map[i] = ctx->ref_tab[i].valid ?
> --
> 2.25.1
> 
_______________________________________________
ffmpeg-devel mailing list
ffmpeg-devel@ffmpeg.org
https://ffmpeg.org/mailman/listinfo/ffmpeg-devel

To unsubscribe, visit link above, or email
ffmpeg-devel-request@ffmpeg.org with subject "unsubscribe".