diff options
| -rw-r--r-- | doc/filters.texi | 32 | ||||
| -rw-r--r-- | libavfilter/vf_fade.c | 55 |
2 files changed, 53 insertions, 34 deletions
diff --git a/doc/filters.texi b/doc/filters.texi index 27b6093b89..0cbbe6b6f3 100644 --- a/doc/filters.texi +++ b/doc/filters.texi @@ -1000,33 +1000,37 @@ For more information about libfreetype, check: Apply fade-in/out effect to input video. -It accepts the parameters: -@var{type}:@var{start_frame}:@var{nb_frames} +This filter accepts the following options: + +@table @option -@var{type} specifies if the effect type, can be either "in" for -fade-in, or "out" for a fade-out effect. +@item type +The effect type -- can be either "in" for fade-in, or "out" for a fade-out +effect. + +@item start_frame +The number of the start frame for starting to apply the fade effect. -@var{start_frame} specifies the number of the start frame for starting -to apply the fade effect. +@item nb_frames +The number of frames for which the fade effect has to last. At the end of the +fade-in effect the output video will have the same intensity as the input video, +at the end of the fade-out transition the output video will be completely black. -@var{nb_frames} specifies the number of frames for which the fade -effect has to last. At the end of the fade-in effect the output video -will have the same intensity as the input video, at the end of the -fade-out transition the output video will be completely black. +@end table A few usage examples follow, usable too as test scenarios. @example # fade in first 30 frames of video -fade=in:0:30 +fade=type=in:nb_frames=30 # fade out last 45 frames of a 200-frame video -fade=out:155:45 +fade=type=out:start_frame=155:nb_frames=45 # fade in first 25 frames and fade out last 25 frames of a 1000-frame video -fade=in:0:25, fade=out:975:25 +fade=type=in:start_frame=0:nb_frames=25, fade=type=out:start_frame=975:nb_frames=25 # make first 5 frames black, then fade in from frame 5-24 -fade=in:5:20 +fade=type=in:start_frame=5:nb_frames=20 @end example @section fieldorder diff --git a/libavfilter/vf_fade.c b/libavfilter/vf_fade.c index f537404ef8..5839c6c9e6 100644 --- a/libavfilter/vf_fade.c +++ b/libavfilter/vf_fade.c @@ -26,48 +26,42 @@ */ #include "libavutil/common.h" +#include "libavutil/opt.h" #include "libavutil/pixdesc.h" #include "avfilter.h" #include "formats.h" #include "internal.h" #include "video.h" +#define FADE_IN 0 +#define FADE_OUT 1 + typedef struct { + const AVClass *class; + int type; int factor, fade_per_frame; - unsigned int frame_index, start_frame, stop_frame; + int start_frame, nb_frames; + unsigned int frame_index, stop_frame; int hsub, vsub, bpp; } FadeContext; static av_cold int init(AVFilterContext *ctx, const char *args) { FadeContext *fade = ctx->priv; - unsigned int nb_frames; - char in_out[4]; - - if (!args || - sscanf(args, " %3[^:]:%u:%u", in_out, &fade->start_frame, &nb_frames) != 3) { - av_log(ctx, AV_LOG_ERROR, - "Expected 3 arguments '(in|out):#:#':'%s'\n", args); - return AVERROR(EINVAL); - } - nb_frames = nb_frames ? nb_frames : 1; - fade->fade_per_frame = (1 << 16) / nb_frames; - if (!strcmp(in_out, "in")) + fade->fade_per_frame = (1 << 16) / fade->nb_frames; + if (fade->type == FADE_IN) { fade->factor = 0; - else if (!strcmp(in_out, "out")) { + } else if (fade->type == FADE_OUT) { fade->fade_per_frame = -fade->fade_per_frame; fade->factor = (1 << 16); - } else { - av_log(ctx, AV_LOG_ERROR, - "first argument must be 'in' or 'out':'%s'\n", in_out); - return AVERROR(EINVAL); } - fade->stop_frame = fade->start_frame + nb_frames; + fade->stop_frame = fade->start_frame + fade->nb_frames; av_log(ctx, AV_LOG_VERBOSE, "type:%s start_frame:%d nb_frames:%d\n", - in_out, fade->start_frame, nb_frames); + fade->type == FADE_IN ? "in" : "out", fade->start_frame, + fade->nb_frames); return 0; } @@ -143,6 +137,26 @@ static int filter_frame(AVFilterLink *inlink, AVFrame *frame) return ff_filter_frame(inlink->dst->outputs[0], frame); } +#define OFFSET(x) offsetof(FadeContext, x) +#define FLAGS AV_OPT_FLAG_VIDEO_PARAM +static const AVOption options[] = { + { "type", "'in' or 'out' for fade-in/fade-out", OFFSET(type), AV_OPT_TYPE_INT, { .i64 = FADE_IN }, FADE_IN, FADE_OUT, FLAGS, "type" }, + { "in", "fade-in", 0, AV_OPT_TYPE_CONST, { .i64 = FADE_IN }, .unit = "type" }, + { "out", "fade-out", 0, AV_OPT_TYPE_CONST, { .i64 = FADE_OUT }, .unit = "type" }, + { "start_frame", "Number of the first frame to which to apply the effect.", + OFFSET(start_frame), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, INT_MAX, FLAGS }, + { "nb_frames", "Number of frames to which the effect should be applied.", + OFFSET(nb_frames), AV_OPT_TYPE_INT, { .i64 = 1 }, 0, INT_MAX, FLAGS }, + { NULL }, +}; + +static const AVClass fade_class = { + .class_name = "fade", + .item_name = av_default_item_name, + .option = options, + .version = LIBAVUTIL_VERSION_INT, +}; + static const AVFilterPad avfilter_vf_fade_inputs[] = { { .name = "default", @@ -168,6 +182,7 @@ AVFilter avfilter_vf_fade = { .description = NULL_IF_CONFIG_SMALL("Fade in/out input video"), .init = init, .priv_size = sizeof(FadeContext), + .priv_class = &fade_class, .query_formats = query_formats, .inputs = avfilter_vf_fade_inputs, |