On Mon, 2022-10-31 at 11:46 -0400, Ruijing Dong wrote:
The title should be "avcodec/av1_vaapi: xxxx".
> [problem]
> When decoding an av1 bitstream, it shows image corruption
> in the middle of the bitstream around key frames.
>
> [analysis]
> 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.
[problem] and [solution] part and title "[analysis]" can be removed in
the commit message. Content after [analysis] is clear enough.
Thanks
Fei
>
> [solution]
> Add show_frame flag as another condition to co-determine
> when to invalidate DPB reference frames.
>
> Mesa fix is in
> https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/19386
>
> cc: Fei Wang <fei.w.w...@intel.com>
> Signed-off-by: Ruijing Dong <ruijing.d...@amd.com>
> ---
> 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)
> pic_param.ref_frame_map[i] = VA_INVALID_ID;
> else
> pic_param.ref_frame_map[i] = ctx->ref_tab[i].valid ?
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