libavfilter/vf_blackdetect.c - manifest_repos/ffmpeg - Git at Google

 /*
  * Copyright (c) 2012 Stefano Sabatini
  *
  * This file is part of FFmpeg.
  *
  * FFmpeg is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
  * License as published by the Free Software Foundation; either
  * version 2.1 of the License, or (at your option) any later version.
  *
  * FFmpeg is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
  * License along with FFmpeg; if not, write to the Free Software
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */

 /**
  * @file
  * Video black detector, loosely based on blackframe with extended
  * syntax and features
  */

 #include <float.h>
 #include "libavutil/opt.h"
 #include "libavutil/pixdesc.h"
 #include "libavutil/timestamp.h"
 #include "avfilter.h"
 #include "internal.h"

 typedef struct BlackDetectContext {
     const AVClass *class;
     double  black_min_duration_time; ///< minimum duration of detected black, in seconds
     int64_t black_min_duration;      ///< minimum duration of detected black, expressed in timebase units
     int64_t black_start;             ///< pts start time of the first black picture
     int64_t black_end;               ///< pts end time of the last black picture
     int64_t last_picref_pts;         ///< pts of the last input picture
     int black_started;

     double       picture_black_ratio_th;
     double       pixel_black_th;
     unsigned int pixel_black_th_i;

     unsigned int nb_black_pixels;   ///< number of black pixels counted so far
     AVRational   time_base;
     int          depth;
     int          nb_threads;
     unsigned int *counter;
 } BlackDetectContext;

 #define OFFSET(x) offsetof(BlackDetectContext, x)
 #define FLAGS AV_OPT_FLAG_VIDEO_PARAM|AV_OPT_FLAG_FILTERING_PARAM

 static const AVOption blackdetect_options[] = {
     { "d",                  "set minimum detected black duration in seconds", OFFSET(black_min_duration_time), AV_OPT_TYPE_DOUBLE, {.dbl=2}, 0, DBL_MAX, FLAGS },
     { "black_min_duration", "set minimum detected black duration in seconds", OFFSET(black_min_duration_time), AV_OPT_TYPE_DOUBLE, {.dbl=2}, 0, DBL_MAX, FLAGS },
     { "picture_black_ratio_th", "set the picture black ratio threshold", OFFSET(picture_black_ratio_th), AV_OPT_TYPE_DOUBLE, {.dbl=.98}, 0, 1, FLAGS },
     { "pic_th",                 "set the picture black ratio threshold", OFFSET(picture_black_ratio_th), AV_OPT_TYPE_DOUBLE, {.dbl=.98}, 0, 1, FLAGS },
     { "pixel_black_th", "set the pixel black threshold", OFFSET(pixel_black_th), AV_OPT_TYPE_DOUBLE, {.dbl=.10}, 0, 1, FLAGS },
     { "pix_th",         "set the pixel black threshold", OFFSET(pixel_black_th), AV_OPT_TYPE_DOUBLE, {.dbl=.10}, 0, 1, FLAGS },
     { NULL }
 };

 AVFILTER_DEFINE_CLASS(blackdetect);

 #define YUVJ_FORMATS \
     AV_PIX_FMT_YUVJ411P, AV_PIX_FMT_YUVJ420P, AV_PIX_FMT_YUVJ422P, AV_PIX_FMT_YUVJ444P, AV_PIX_FMT_YUVJ440P

 static const enum AVPixelFormat yuvj_formats[] = {
     YUVJ_FORMATS, AV_PIX_FMT_NONE
 };

 static int query_formats(AVFilterContext *ctx)
 {
     static const enum AVPixelFormat pix_fmts[] = {
         AV_PIX_FMT_GRAY8,
         AV_PIX_FMT_YUV410P, AV_PIX_FMT_YUV411P,
         AV_PIX_FMT_YUV420P, AV_PIX_FMT_YUV422P,
         AV_PIX_FMT_YUV440P, AV_PIX_FMT_YUV444P,
         AV_PIX_FMT_NV12, AV_PIX_FMT_NV21,
         YUVJ_FORMATS,
         AV_PIX_FMT_GRAY10, AV_PIX_FMT_GRAY12, AV_PIX_FMT_GRAY14,
         AV_PIX_FMT_GRAY16,
         AV_PIX_FMT_YUV420P9, AV_PIX_FMT_YUV422P9, AV_PIX_FMT_YUV444P9,
         AV_PIX_FMT_YUV420P10, AV_PIX_FMT_YUV422P10, AV_PIX_FMT_YUV444P10,
         AV_PIX_FMT_YUV440P10,
         AV_PIX_FMT_YUV444P12, AV_PIX_FMT_YUV422P12, AV_PIX_FMT_YUV420P12,
         AV_PIX_FMT_YUV440P12,
         AV_PIX_FMT_YUV444P14, AV_PIX_FMT_YUV422P14, AV_PIX_FMT_YUV420P14,
         AV_PIX_FMT_YUV420P16, AV_PIX_FMT_YUV422P16, AV_PIX_FMT_YUV444P16,
         AV_PIX_FMT_YUVA420P,  AV_PIX_FMT_YUVA422P,   AV_PIX_FMT_YUVA444P,
         AV_PIX_FMT_YUVA444P9, AV_PIX_FMT_YUVA444P10, AV_PIX_FMT_YUVA444P12, AV_PIX_FMT_YUVA444P16,
         AV_PIX_FMT_YUVA422P9, AV_PIX_FMT_YUVA422P10, AV_PIX_FMT_YUVA422P12, AV_PIX_FMT_YUVA422P16,
         AV_PIX_FMT_YUVA420P9, AV_PIX_FMT_YUVA420P10, AV_PIX_FMT_YUVA420P16,
         AV_PIX_FMT_NONE
     };

     AVFilterFormats *fmts_list = ff_make_format_list(pix_fmts);
     if (!fmts_list)
         return AVERROR(ENOMEM);
     return ff_set_common_formats(ctx, fmts_list);
 }

 static int config_input(AVFilterLink *inlink)
 {
     AVFilterContext *ctx = inlink->dst;
     BlackDetectContext *s = ctx->priv;
     const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(inlink->format);
     const int depth = desc->comp[0].depth;
     const int max = (1 << depth) - 1;
     const int factor = (1 << (depth - 8));

     s->depth = depth;
     s->nb_threads = ff_filter_get_nb_threads(ctx);
     s->time_base = inlink->time_base;
     s->black_min_duration = s->black_min_duration_time / av_q2d(s->time_base);
     s->counter = av_calloc(s->nb_threads, sizeof(*s->counter));
     if (!s->counter)
         return AVERROR(ENOMEM);

     s->pixel_black_th_i = ff_fmt_is_in(inlink->format, yuvj_formats) ?
         // luminance_minimum_value + pixel_black_th * luminance_range_size
              s->pixel_black_th *  max :
         16 * factor + s->pixel_black_th * (235 - 16) * factor;

     av_log(s, AV_LOG_VERBOSE,
            "black_min_duration:%s pixel_black_th:%f pixel_black_th_i:%d picture_black_ratio_th:%f\n",
            av_ts2timestr(s->black_min_duration, &s->time_base),
            s->pixel_black_th, s->pixel_black_th_i,
            s->picture_black_ratio_th);
     return 0;
 }

 static void check_black_end(AVFilterContext *ctx)
 {
     BlackDetectContext *s = ctx->priv;

     if ((s->black_end - s->black_start) >= s->black_min_duration) {
         av_log(s, AV_LOG_INFO,
                "black_start:%s black_end:%s black_duration:%s\n",
                av_ts2timestr(s->black_start, &s->time_base),
                av_ts2timestr(s->black_end,   &s->time_base),
                av_ts2timestr(s->black_end - s->black_start, &s->time_base));
     }
 }

 static int black_counter(AVFilterContext *ctx, void *arg,
                          int jobnr, int nb_jobs)
 {
     BlackDetectContext *s = ctx->priv;
     const unsigned int threshold = s->pixel_black_th_i;
     unsigned int *counterp = &s->counter[jobnr];
     AVFrame *in = arg;
     const int linesize = in->linesize[0];
     const int w = in->width;
     const int h = in->height;
     const int start = (h * jobnr) / nb_jobs;
     const int end = (h * (jobnr+1)) / nb_jobs;
     const int size = end - start;
     unsigned int counter = 0;

     if (s->depth == 8) {
         const uint8_t *p = in->data[0] + start * linesize;

         for (int i = 0; i < size; i++) {
             for (int x = 0; x < w; x++)
                 counter += p[x] <= threshold;
             p += linesize;
         }
     } else {
         const uint16_t *p = (const uint16_t *)(in->data[0] + start * linesize);

         for (int i = 0; i < size; i++) {
             for (int x = 0; x < w; x++)
                 counter += p[x] <= threshold;
             p += linesize / 2;
         }
     }

     *counterp = counter;

     return 0;
 }

 static int filter_frame(AVFilterLink *inlink, AVFrame *picref)
 {
     AVFilterContext *ctx = inlink->dst;
     BlackDetectContext *s = ctx->priv;
     double picture_black_ratio = 0;

     ctx->internal->execute(ctx, black_counter, picref, NULL,
                            FFMIN(inlink->h, s->nb_threads));

     for (int i = 0; i < s->nb_threads; i++)
         s->nb_black_pixels += s->counter[i];

     picture_black_ratio = (double)s->nb_black_pixels / (inlink->w * inlink->h);

     av_log(ctx, AV_LOG_DEBUG,
            "frame:%"PRId64" picture_black_ratio:%f pts:%s t:%s type:%c\n",
            inlink->frame_count_out, picture_black_ratio,
            av_ts2str(picref->pts), av_ts2timestr(picref->pts, &s->time_base),
            av_get_picture_type_char(picref->pict_type));

     if (picture_black_ratio >= s->picture_black_ratio_th) {
         if (!s->black_started) {
             /* black starts here */
             s->black_started = 1;
             s->black_start = picref->pts;
             av_dict_set(&picref->metadata, "lavfi.black_start",
                 av_ts2timestr(s->black_start, &s->time_base), 0);
         }
     } else if (s->black_started) {
         /* black ends here */
         s->black_started = 0;
         s->black_end = picref->pts;
         check_black_end(ctx);
         av_dict_set(&picref->metadata, "lavfi.black_end",
             av_ts2timestr(s->black_end, &s->time_base), 0);
     }

     s->last_picref_pts = picref->pts;
     s->nb_black_pixels = 0;
     return ff_filter_frame(inlink->dst->outputs[0], picref);
 }

 static av_cold void uninit(AVFilterContext *ctx)
 {
     BlackDetectContext *s = ctx->priv;

     av_freep(&s->counter);

     if (s->black_started) {
         // FIXME: black_end should be set to last_picref_pts + last_picref_duration
         s->black_end = s->last_picref_pts;
         check_black_end(ctx);
     }
 }

 static const AVFilterPad blackdetect_inputs[] = {
     {
         .name          = "default",
         .type          = AVMEDIA_TYPE_VIDEO,
         .config_props  = config_input,
         .filter_frame  = filter_frame,
     },
     { NULL }
 };

 static const AVFilterPad blackdetect_outputs[] = {
     {
         .name          = "default",
         .type          = AVMEDIA_TYPE_VIDEO,
     },
     { NULL }
 };

 AVFilter ff_vf_blackdetect = {
     .name          = "blackdetect",
     .description   = NULL_IF_CONFIG_SMALL("Detect video intervals that are (almost) black."),
     .priv_size     = sizeof(BlackDetectContext),
     .query_formats = query_formats,
     .inputs        = blackdetect_inputs,
     .outputs       = blackdetect_outputs,
     .uninit        = uninit,
     .priv_class    = &blackdetect_class,
     .flags         = AVFILTER_FLAG_SLICE_THREADS,
 };
	/*
	* Copyright (c) 2012 Stefano Sabatini
	*
	* This file is part of FFmpeg.
	*
	* FFmpeg is free software; you can redistribute it and/or
	* modify it under the terms of the GNU Lesser General Public
	* License as published by the Free Software Foundation; either
	* version 2.1 of the License, or (at your option) any later version.
	*
	* FFmpeg is distributed in the hope that it will be useful,
	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	* Lesser General Public License for more details.
	*
	* You should have received a copy of the GNU Lesser General Public
	* License along with FFmpeg; if not, write to the Free Software
	* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
	*/

	/**
	* @file
	* Video black detector, loosely based on blackframe with extended
	* syntax and features
	*/

	#include <float.h>
	#include "libavutil/opt.h"
	#include "libavutil/pixdesc.h"
	#include "libavutil/timestamp.h"
	#include "avfilter.h"
	#include "internal.h"

	typedef struct BlackDetectContext {
	const AVClass *class;
	double black_min_duration_time; ///< minimum duration of detected black, in seconds
	int64_t black_min_duration; ///< minimum duration of detected black, expressed in timebase units
	int64_t black_start; ///< pts start time of the first black picture
	int64_t black_end; ///< pts end time of the last black picture
	int64_t last_picref_pts; ///< pts of the last input picture
	int black_started;

	double picture_black_ratio_th;
	double pixel_black_th;
	unsigned int pixel_black_th_i;

	unsigned int nb_black_pixels; ///< number of black pixels counted so far
	AVRational time_base;
	int depth;
	int nb_threads;
	unsigned int *counter;
	} BlackDetectContext;

	#define OFFSET(x) offsetof(BlackDetectContext, x)
	#define FLAGS AV_OPT_FLAG_VIDEO_PARAM\|AV_OPT_FLAG_FILTERING_PARAM

	static const AVOption blackdetect_options[] = {
	{ "d", "set minimum detected black duration in seconds", OFFSET(black_min_duration_time), AV_OPT_TYPE_DOUBLE, {.dbl=2}, 0, DBL_MAX, FLAGS },
	{ "black_min_duration", "set minimum detected black duration in seconds", OFFSET(black_min_duration_time), AV_OPT_TYPE_DOUBLE, {.dbl=2}, 0, DBL_MAX, FLAGS },
	{ "picture_black_ratio_th", "set the picture black ratio threshold", OFFSET(picture_black_ratio_th), AV_OPT_TYPE_DOUBLE, {.dbl=.98}, 0, 1, FLAGS },
	{ "pic_th", "set the picture black ratio threshold", OFFSET(picture_black_ratio_th), AV_OPT_TYPE_DOUBLE, {.dbl=.98}, 0, 1, FLAGS },
	{ "pixel_black_th", "set the pixel black threshold", OFFSET(pixel_black_th), AV_OPT_TYPE_DOUBLE, {.dbl=.10}, 0, 1, FLAGS },
	{ "pix_th", "set the pixel black threshold", OFFSET(pixel_black_th), AV_OPT_TYPE_DOUBLE, {.dbl=.10}, 0, 1, FLAGS },
	{ NULL }
	};

	AVFILTER_DEFINE_CLASS(blackdetect);

	#define YUVJ_FORMATS \
	AV_PIX_FMT_YUVJ411P, AV_PIX_FMT_YUVJ420P, AV_PIX_FMT_YUVJ422P, AV_PIX_FMT_YUVJ444P, AV_PIX_FMT_YUVJ440P

	static const enum AVPixelFormat yuvj_formats[] = {
	YUVJ_FORMATS, AV_PIX_FMT_NONE
	};

	static int query_formats(AVFilterContext *ctx)
	{
	static const enum AVPixelFormat pix_fmts[] = {
	AV_PIX_FMT_GRAY8,
	AV_PIX_FMT_YUV410P, AV_PIX_FMT_YUV411P,
	AV_PIX_FMT_YUV420P, AV_PIX_FMT_YUV422P,
	AV_PIX_FMT_YUV440P, AV_PIX_FMT_YUV444P,
	AV_PIX_FMT_NV12, AV_PIX_FMT_NV21,
	YUVJ_FORMATS,
	AV_PIX_FMT_GRAY10, AV_PIX_FMT_GRAY12, AV_PIX_FMT_GRAY14,
	AV_PIX_FMT_GRAY16,
	AV_PIX_FMT_YUV420P9, AV_PIX_FMT_YUV422P9, AV_PIX_FMT_YUV444P9,
	AV_PIX_FMT_YUV420P10, AV_PIX_FMT_YUV422P10, AV_PIX_FMT_YUV444P10,
	AV_PIX_FMT_YUV440P10,
	AV_PIX_FMT_YUV444P12, AV_PIX_FMT_YUV422P12, AV_PIX_FMT_YUV420P12,
	AV_PIX_FMT_YUV440P12,
	AV_PIX_FMT_YUV444P14, AV_PIX_FMT_YUV422P14, AV_PIX_FMT_YUV420P14,
	AV_PIX_FMT_YUV420P16, AV_PIX_FMT_YUV422P16, AV_PIX_FMT_YUV444P16,
	AV_PIX_FMT_YUVA420P, AV_PIX_FMT_YUVA422P, AV_PIX_FMT_YUVA444P,
	AV_PIX_FMT_YUVA444P9, AV_PIX_FMT_YUVA444P10, AV_PIX_FMT_YUVA444P12, AV_PIX_FMT_YUVA444P16,
	AV_PIX_FMT_YUVA422P9, AV_PIX_FMT_YUVA422P10, AV_PIX_FMT_YUVA422P12, AV_PIX_FMT_YUVA422P16,
	AV_PIX_FMT_YUVA420P9, AV_PIX_FMT_YUVA420P10, AV_PIX_FMT_YUVA420P16,
	AV_PIX_FMT_NONE
	};

	AVFilterFormats *fmts_list = ff_make_format_list(pix_fmts);
	if (!fmts_list)
	return AVERROR(ENOMEM);
	return ff_set_common_formats(ctx, fmts_list);
	}

	static int config_input(AVFilterLink *inlink)
	{
	AVFilterContext *ctx = inlink->dst;
	BlackDetectContext *s = ctx->priv;
	const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(inlink->format);
	const int depth = desc->comp[0].depth;
	const int max = (1 << depth) - 1;
	const int factor = (1 << (depth - 8));

	s->depth = depth;
	s->nb_threads = ff_filter_get_nb_threads(ctx);
	s->time_base = inlink->time_base;
	s->black_min_duration = s->black_min_duration_time / av_q2d(s->time_base);
	s->counter = av_calloc(s->nb_threads, sizeof(*s->counter));
	if (!s->counter)
	return AVERROR(ENOMEM);

	s->pixel_black_th_i = ff_fmt_is_in(inlink->format, yuvj_formats) ?
	// luminance_minimum_value + pixel_black_th * luminance_range_size
	s->pixel_black_th * max :
	16 * factor + s->pixel_black_th * (235 - 16) * factor;

	av_log(s, AV_LOG_VERBOSE,
	"black_min_duration:%s pixel_black_th:%f pixel_black_th_i:%d picture_black_ratio_th:%f\n",
	av_ts2timestr(s->black_min_duration, &s->time_base),
	s->pixel_black_th, s->pixel_black_th_i,
	s->picture_black_ratio_th);
	return 0;
	}

	static void check_black_end(AVFilterContext *ctx)
	{
	BlackDetectContext *s = ctx->priv;

	if ((s->black_end - s->black_start) >= s->black_min_duration) {
	av_log(s, AV_LOG_INFO,
	"black_start:%s black_end:%s black_duration:%s\n",
	av_ts2timestr(s->black_start, &s->time_base),
	av_ts2timestr(s->black_end, &s->time_base),
	av_ts2timestr(s->black_end - s->black_start, &s->time_base));
	}
	}

	static int black_counter(AVFilterContext ctx, void arg,
	int jobnr, int nb_jobs)
	{
	BlackDetectContext *s = ctx->priv;
	const unsigned int threshold = s->pixel_black_th_i;
	unsigned int *counterp = &s->counter[jobnr];
	AVFrame *in = arg;
	const int linesize = in->linesize[0];
	const int w = in->width;
	const int h = in->height;
	const int start = (h * jobnr) / nb_jobs;
	const int end = (h * (jobnr+1)) / nb_jobs;
	const int size = end - start;
	unsigned int counter = 0;

	if (s->depth == 8) {
	const uint8_t p = in->data[0] + start linesize;

	for (int i = 0; i < size; i++) {
	for (int x = 0; x < w; x++)
	counter += p[x] <= threshold;
	p += linesize;
	}
	} else {
	const uint16_t p = (const uint16_t )(in->data[0] + start * linesize);

	for (int i = 0; i < size; i++) {
	for (int x = 0; x < w; x++)
	counter += p[x] <= threshold;
	p += linesize / 2;
	}
	}

	*counterp = counter;

	return 0;
	}

	static int filter_frame(AVFilterLink inlink, AVFrame picref)
	{
	AVFilterContext *ctx = inlink->dst;
	BlackDetectContext *s = ctx->priv;
	double picture_black_ratio = 0;

	ctx->internal->execute(ctx, black_counter, picref, NULL,
	FFMIN(inlink->h, s->nb_threads));

	for (int i = 0; i < s->nb_threads; i++)
	s->nb_black_pixels += s->counter[i];

	picture_black_ratio = (double)s->nb_black_pixels / (inlink->w * inlink->h);

	av_log(ctx, AV_LOG_DEBUG,
	"frame:%"PRId64" picture_black_ratio:%f pts:%s t:%s type:%c\n",
	inlink->frame_count_out, picture_black_ratio,
	av_ts2str(picref->pts), av_ts2timestr(picref->pts, &s->time_base),
	av_get_picture_type_char(picref->pict_type));

	if (picture_black_ratio >= s->picture_black_ratio_th) {
	if (!s->black_started) {
	/* black starts here */
	s->black_started = 1;
	s->black_start = picref->pts;
	av_dict_set(&picref->metadata, "lavfi.black_start",
	av_ts2timestr(s->black_start, &s->time_base), 0);
	}
	} else if (s->black_started) {
	/* black ends here */
	s->black_started = 0;
	s->black_end = picref->pts;
	check_black_end(ctx);
	av_dict_set(&picref->metadata, "lavfi.black_end",
	av_ts2timestr(s->black_end, &s->time_base), 0);
	}

	s->last_picref_pts = picref->pts;
	s->nb_black_pixels = 0;
	return ff_filter_frame(inlink->dst->outputs[0], picref);
	}

	static av_cold void uninit(AVFilterContext *ctx)
	{
	BlackDetectContext *s = ctx->priv;

	av_freep(&s->counter);

	if (s->black_started) {
	// FIXME: black_end should be set to last_picref_pts + last_picref_duration
	s->black_end = s->last_picref_pts;
	check_black_end(ctx);
	}
	}

	static const AVFilterPad blackdetect_inputs[] = {
	{
	.name = "default",
	.type = AVMEDIA_TYPE_VIDEO,
	.config_props = config_input,
	.filter_frame = filter_frame,
	},
	{ NULL }
	};

	static const AVFilterPad blackdetect_outputs[] = {
	{
	.name = "default",
	.type = AVMEDIA_TYPE_VIDEO,
	},
	{ NULL }
	};

	AVFilter ff_vf_blackdetect = {
	.name = "blackdetect",
	.description = NULL_IF_CONFIG_SMALL("Detect video intervals that are (almost) black."),
	.priv_size = sizeof(BlackDetectContext),
	.query_formats = query_formats,
	.inputs = blackdetect_inputs,
	.outputs = blackdetect_outputs,
	.uninit = uninit,
	.priv_class = &blackdetect_class,
	.flags = AVFILTER_FLAG_SLICE_THREADS,
	};