[FFmpeg-devel] [PATCH] avcodec/hevcdec: constrained intra predict, do not check top left IS_INTRA if it's not available

[Guangxin Xu]

The bug reporter confirmed the fix.
https://trac.ffmpeg.org/ticket/8932

ping for review and merge.
thanks

On Fri, Oct 16, 2020 at 9:57 PM Xu Guangxin <oddstone at gmail.com> wrote:

> fix ticket: 8932
>
> For poc 2, we have tile boundary at x = 640.
> When we predict cu(640,912),the top left pixel is not avaliable to the cu.
> So, we can not check it's intra or not. We need set top[-1] = top[0]
> directly.
> see 8.4.4.2.1 for details
> ---
>  libavcodec/hevcpred_template.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/libavcodec/hevcpred_template.c
> b/libavcodec/hevcpred_template.c
> index 6fe33546b1..e550707874 100644
> --- a/libavcodec/hevcpred_template.c
> +++ b/libavcodec/hevcpred_template.c
> @@ -213,7 +213,7 @@ do {                                  \
>                  while (j < size_max_x && !IS_INTRA(j, -1))
>                      j++;
>                  if (j > 0)
> -                    if (x0 > 0) {
> +                    if (cand_up_left) {
>                          EXTEND_LEFT_CIP(top, j, j + 1);
>                      } else {
>                          EXTEND_LEFT_CIP(top, j, j);
> --
> 2.17.1
>
>