[FFmpeg-devel] [PATCH] avfilter/colorize: add speed option

[Gyan Doshi]

On 2024-05-01 12:18 pm, Yannis Gerlach wrote:
> The speed option allows to have a constant (per frame) change of hue. 
> This allows for an easy way of creating an color changing effect 
> without relying on somewhat complicated expressions.
>
> Signed-off-by: Yannis Gerlach <ffmpeg at ygerlach.de>
> ---
>  libavfilter/vf_colorize.c | 17 +++++++++++++----
>  1 file changed, 13 insertions(+), 4 deletions(-)
>
> diff --git a/libavfilter/vf_colorize.c b/libavfilter/vf_colorize.c
> index e6c563e3e2..ad8577c8fd 100644
> --- a/libavfilter/vf_colorize.c
> +++ b/libavfilter/vf_colorize.c
> @@ -29,6 +29,7 @@ typedef struct ColorizeContext {
>      float saturation;
>      float lightness;
>      float mix;
> +    float speed;
>       int depth;
>      int c[3];
> @@ -205,6 +206,13 @@ static int filter_frame(AVFilterLink *inlink, 
> AVFrame *frame)
>      ff_filter_execute(ctx, do_slice, frame, NULL,
>                        FFMIN(s->planeheight[1], 
> ff_filter_get_nb_threads(ctx)));
>  +    s->hue += s->speed;
> +    if (s->hue < 0.f) {
> +        s->hue += 360.f;
> +    } else if(s->hue > 360.f) {
> +        s->hue -= 360.f;
> +    }
> +
>      return ff_filter_frame(ctx->outputs[0], frame);
>  }
>  @@ -263,10 +271,11 @@ static const AVFilterPad colorize_inputs[] = {
>  #define VF 
> AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM|AV_OPT_FLAG_RUNTIME_PARAM
>   static const AVOption colorize_options[] = {
> -    { "hue",        "set the hue", OFFSET(hue),    AV_OPT_TYPE_FLOAT, 
> {.dbl=0},  0, 360, VF },
> -    { "saturation", "set the saturation", OFFSET(saturation), 
> AV_OPT_TYPE_FLOAT, {.dbl=0.5},0,   1, VF },
> -    { "lightness",  "set the lightness", OFFSET(lightness), 
> AV_OPT_TYPE_FLOAT, {.dbl=0.5},0,   1, VF },
> -    { "mix",        "set the mix of source lightness", OFFSET(mix), 
>    AV_OPT_TYPE_FLOAT, {.dbl=1},  0,   1, VF },
> +    { "hue",        "set the hue", OFFSET(hue),    AV_OPT_TYPE_FLOAT, 
> {.dbl=0},    0, 360, VF },
> +    { "saturation", "set the saturation", OFFSET(saturation), 
> AV_OPT_TYPE_FLOAT, {.dbl=0.5},  0,   1, VF },
> +    { "lightness",  "set the lightness", OFFSET(lightness), 
> AV_OPT_TYPE_FLOAT, {.dbl=0.5},  0,   1, VF },
> +    { "mix",        "set the mix of source lightness", OFFSET(mix), 
>    AV_OPT_TYPE_FLOAT, {.dbl=1},    0,   1, VF },

The cosmetic changes should be in a separate patch.

Regards,
Gyan

> +    { "speed",      "set the change of hue per frame", OFFSET(speed), 
> AV_OPT_TYPE_FLOAT, {.dbl=0}, -180, 180, VF },
>      { NULL }
>  };
>  -- 2.34.1
>
> _______________________________________________
> ffmpeg-devel mailing list
> ffmpeg-devel at ffmpeg.org
> https://ffmpeg.org/mailman/listinfo/ffmpeg-devel
>
> To unsubscribe, visit link above, or email
> ffmpeg-devel-request at ffmpeg.org with subject "unsubscribe".