Quoting Martin Storsjö (2017-02-16 11:33:36)
> When slice_h is rounded up due to chroma subsampling, there's
> a risk that jobnr * slice_h exceeds frame->height.
> 
> Prior to a638e9184d63, this wasn't an issue for the last slice
> of a frame, since slice_end was set to frame->height for the last
> slice.
> 
> a638e9184d63 tried to fix the case where other slices than the
> last one would exceed frame->height (which can happen where the
> number of slices/threads is very large compared to the frame
> height).
> 
> However, the fix in a638e9184d63 instead broke other cases,
> where slice_h * nb_threads < frame->height. Therefore, make
> sure the last slice always ends at frame->height.
> 
> CC: libav-sta...@libav.org
> ---
>  libavfilter/vf_fade.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/libavfilter/vf_fade.c b/libavfilter/vf_fade.c
> index eb6d82a..fd8c6ef 100644
> --- a/libavfilter/vf_fade.c
> +++ b/libavfilter/vf_fade.c
> @@ -123,7 +123,8 @@ static int filter_slice_chroma(AVFilterContext *ctx, void 
> *arg, int jobnr,
>      AVFrame *frame = arg;
>      int slice_h     = FFALIGN(frame->height / nb_jobs, 1 << s->vsub);
>      int slice_start = jobnr * slice_h;
> -    int slice_end   = FFMIN((jobnr + 1) * slice_h, frame->height);
> +    int slice_end   = (jobnr == nb_jobs - 1) ? frame->height :
> +                                               FFMIN((jobnr + 1) * slice_h, 
> frame->height);
>      int i, j, plane;
>  
>      for (plane = 1; plane < 3; plane++) {
> -- 
> 2.10.1 (Apple Git-78)

Looks good, thanks for the fix.

-- 
Anton Khirnov
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