[FFmpeg-devel] [PATCH v2 1/3] avfilter/vf_bwdif: consider chroma subsampling when enforcing minimum dimensions

[Thomas Mundt]

Am Do., 30. Nov. 2023 um 01:23 Uhr schrieb Cosmin Stejerean via
ffmpeg-devel <ffmpeg-devel at ffmpeg.org>:

> From: Cosmin Stejerean <cosmin at cosmin.at>
>
> Fixes #10688
>
> Signed-off-by: Cosmin Stejerean <cosmin at cosmin.at>
> ---
>  libavfilter/vf_bwdif.c | 13 ++++++++++---
>  1 file changed, 10 insertions(+), 3 deletions(-)
>
> diff --git a/libavfilter/vf_bwdif.c b/libavfilter/vf_bwdif.c
> index 137cd5ef13..80aa85a48b 100644
> --- a/libavfilter/vf_bwdif.c
> +++ b/libavfilter/vf_bwdif.c
> @@ -191,12 +191,19 @@ static int config_props(AVFilterLink *link)
>          return ret;
>      }
>
> -    if (link->w < 3 || link->h < 4) {
> -        av_log(ctx, AV_LOG_ERROR, "Video of less than 3 columns or 4
> lines is not supported\n");
> +    const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(link->format);
> +
> +    int h = link->h;
> +    int w = link->w;
> +    int h_chroma = AV_CEIL_RSHIFT(h, desc->log2_chroma_h);
> +    int w_chroma = AV_CEIL_RSHIFT(w, desc->log2_chroma_w);
> +
> +    if (w < 3 || w_chroma < 3 || h < 4 || h_chroma < 4) {
> +        av_log(ctx, AV_LOG_ERROR, "Video with planes less than 3 columns
> or 4 lines is not supported\n");
>          return AVERROR(EINVAL);
>      }
>
> -    yadif->csp = av_pix_fmt_desc_get(link->format);
> +    yadif->csp = desc;
>      yadif->filter = filter;
>      ff_bwdif_init_filter_line(&s->dsp, yadif->csp->comp[0].depth);
>
> I think mixed declarations are not allowed.
Also log2_chroma_w/h should never be negative, so why not just do:

if (AV_CEIL_RSHIFT(link->w,  yadif->csp->log2_chroma_w) < 3 ||
    AV_CEIL_RSHIFT(link->h,  yadif->csp->log2_chroma_h) < 4)

Regards,
Thomas