[FFmpeg-devel] [PATCH 2/2] avfilter/vf_chromakey: fix formula for calculation of difference

[Paul B Mahol]

Will apply soon.

On 5/16/20, Paul B Mahol <onemda at gmail.com> wrote:
> Signed-off-by: Paul B Mahol <onemda at gmail.com>
> ---
>  libavfilter/vf_chromakey.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/libavfilter/vf_chromakey.c b/libavfilter/vf_chromakey.c
> index ce8003657c..4b1669d084 100644
> --- a/libavfilter/vf_chromakey.c
> +++ b/libavfilter/vf_chromakey.c
> @@ -56,7 +56,7 @@ static uint8_t do_chromakey_pixel(ChromakeyContext *ctx,
> uint8_t u[9], uint8_t v
>          du = (int)u[i] - ctx->chromakey_uv[0];
>          dv = (int)v[i] - ctx->chromakey_uv[1];
>
> -        diff += sqrt((du * du + dv * dv) / (255.0 * 255.0));
> +        diff += sqrt((du * du + dv * dv) / (255.0 * 255.0 * 2));
>      }
>
>      diff /= 9.0;
> @@ -78,7 +78,7 @@ static uint16_t do_chromakey_pixel16(ChromakeyContext
> *ctx, uint16_t u[9], uint1
>          du = (int)u[i] - ctx->chromakey_uv[0];
>          dv = (int)v[i] - ctx->chromakey_uv[1];
>
> -        diff += sqrt((du * du + dv * dv) / (max * max));
> +        diff += sqrt((du * du + dv * dv) / (max * max * 2));
>      }
>
>      diff /= 9.0;
> --
> 2.17.1
>
>