mirror of
https://git.videolan.org/git/ffmpeg.git
synced 2024-08-27 11:51:49 +02:00
220 lines
8.0 KiB
C
220 lines
8.0 KiB
C
/*
|
|
* 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/timestamp.h"
|
|
#include "avfilter.h"
|
|
#include "internal.h"
|
|
|
|
typedef struct {
|
|
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 frame_count; ///< frame number
|
|
unsigned int nb_black_pixels; ///< number of black pixels counted so far
|
|
} 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_YUVJ420P, AV_PIX_FMT_YUVJ422P, AV_PIX_FMT_YUVJ444P, AV_PIX_FMT_YUVJ440P
|
|
|
|
static 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_YUV410P, AV_PIX_FMT_YUV420P, AV_PIX_FMT_GRAY8, AV_PIX_FMT_NV12,
|
|
AV_PIX_FMT_NV21, AV_PIX_FMT_YUV444P, AV_PIX_FMT_YUV422P, AV_PIX_FMT_YUV411P,
|
|
YUVJ_FORMATS,
|
|
AV_PIX_FMT_NONE
|
|
};
|
|
|
|
ff_set_common_formats(ctx, ff_make_format_list(pix_fmts));
|
|
return 0;
|
|
}
|
|
|
|
static av_cold int init(AVFilterContext *ctx, const char *args)
|
|
{
|
|
int ret;
|
|
BlackDetectContext *blackdetect = ctx->priv;
|
|
|
|
blackdetect->class = &blackdetect_class;
|
|
av_opt_set_defaults(blackdetect);
|
|
|
|
if ((ret = av_set_options_string(blackdetect, args, "=", ":")) < 0)
|
|
return ret;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int config_input(AVFilterLink *inlink)
|
|
{
|
|
AVFilterContext *ctx = inlink->dst;
|
|
BlackDetectContext *blackdetect = ctx->priv;
|
|
|
|
blackdetect->black_min_duration =
|
|
blackdetect->black_min_duration_time / av_q2d(inlink->time_base);
|
|
|
|
blackdetect->pixel_black_th_i = ff_fmt_is_in(inlink->format, yuvj_formats) ?
|
|
// luminance_minimum_value + pixel_black_th * luminance_range_size
|
|
blackdetect->pixel_black_th * 255 :
|
|
16 + blackdetect->pixel_black_th * (235 - 16);
|
|
|
|
av_log(blackdetect, AV_LOG_VERBOSE,
|
|
"black_min_duration:%s pixel_black_th:%f pixel_black_th_i:%d picture_black_ratio_th:%f\n",
|
|
av_ts2timestr(blackdetect->black_min_duration, &inlink->time_base),
|
|
blackdetect->pixel_black_th, blackdetect->pixel_black_th_i,
|
|
blackdetect->picture_black_ratio_th);
|
|
return 0;
|
|
}
|
|
|
|
static void check_black_end(AVFilterContext *ctx)
|
|
{
|
|
BlackDetectContext *blackdetect = ctx->priv;
|
|
AVFilterLink *inlink = ctx->inputs[0];
|
|
|
|
if ((blackdetect->black_end - blackdetect->black_start) >= blackdetect->black_min_duration) {
|
|
av_log(blackdetect, AV_LOG_INFO,
|
|
"black_start:%s black_end:%s black_duration:%s\n",
|
|
av_ts2timestr(blackdetect->black_start, &inlink->time_base),
|
|
av_ts2timestr(blackdetect->black_end, &inlink->time_base),
|
|
av_ts2timestr(blackdetect->black_end - blackdetect->black_start, &inlink->time_base));
|
|
}
|
|
}
|
|
|
|
static int request_frame(AVFilterLink *outlink)
|
|
{
|
|
AVFilterContext *ctx = outlink->src;
|
|
BlackDetectContext *blackdetect = ctx->priv;
|
|
AVFilterLink *inlink = ctx->inputs[0];
|
|
int ret = ff_request_frame(inlink);
|
|
|
|
if (ret == AVERROR_EOF && blackdetect->black_started) {
|
|
// FIXME: black_end should be set to last_picref_pts + last_picref_duration
|
|
blackdetect->black_end = blackdetect->last_picref_pts;
|
|
check_black_end(ctx);
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
static int filter_frame(AVFilterLink *inlink, AVFilterBufferRef *picref)
|
|
{
|
|
AVFilterContext *ctx = inlink->dst;
|
|
BlackDetectContext *blackdetect = ctx->priv;
|
|
double picture_black_ratio = 0;
|
|
const uint8_t *p = picref->data[0];
|
|
int x, i;
|
|
|
|
for (i = 0; i < inlink->h; i++) {
|
|
for (x = 0; x < inlink->w; x++)
|
|
blackdetect->nb_black_pixels += p[x] <= blackdetect->pixel_black_th_i;
|
|
p += picref->linesize[0];
|
|
}
|
|
|
|
picture_black_ratio = (double)blackdetect->nb_black_pixels / (inlink->w * inlink->h);
|
|
|
|
av_log(ctx, AV_LOG_DEBUG,
|
|
"frame:%u picture_black_ratio:%f pos:%"PRId64" pts:%s t:%s type:%c\n",
|
|
blackdetect->frame_count, picture_black_ratio,
|
|
picref->pos, av_ts2str(picref->pts), av_ts2timestr(picref->pts, &inlink->time_base),
|
|
av_get_picture_type_char(picref->video->pict_type));
|
|
|
|
if (picture_black_ratio >= blackdetect->picture_black_ratio_th) {
|
|
if (!blackdetect->black_started) {
|
|
/* black starts here */
|
|
blackdetect->black_started = 1;
|
|
blackdetect->black_start = picref->pts;
|
|
}
|
|
} else if (blackdetect->black_started) {
|
|
/* black ends here */
|
|
blackdetect->black_started = 0;
|
|
blackdetect->black_end = picref->pts;
|
|
check_black_end(ctx);
|
|
}
|
|
|
|
blackdetect->last_picref_pts = picref->pts;
|
|
blackdetect->frame_count++;
|
|
blackdetect->nb_black_pixels = 0;
|
|
return ff_filter_frame(inlink->dst->outputs[0], picref);
|
|
}
|
|
|
|
static const AVFilterPad blackdetect_inputs[] = {
|
|
{
|
|
.name = "default",
|
|
.type = AVMEDIA_TYPE_VIDEO,
|
|
.config_props = config_input,
|
|
.get_video_buffer = ff_null_get_video_buffer,
|
|
.filter_frame = filter_frame,
|
|
},
|
|
{ NULL }
|
|
};
|
|
|
|
static const AVFilterPad blackdetect_outputs[] = {
|
|
{
|
|
.name = "default",
|
|
.type = AVMEDIA_TYPE_VIDEO,
|
|
.request_frame = request_frame,
|
|
},
|
|
{ NULL }
|
|
};
|
|
|
|
AVFilter avfilter_vf_blackdetect = {
|
|
.name = "blackdetect",
|
|
.description = NULL_IF_CONFIG_SMALL("Detect video intervals that are (almost) black."),
|
|
.priv_size = sizeof(BlackDetectContext),
|
|
.init = init,
|
|
.query_formats = query_formats,
|
|
.inputs = blackdetect_inputs,
|
|
.outputs = blackdetect_outputs,
|
|
.priv_class = &blackdetect_class,
|
|
};
|