Imported Debian version 2.4.3~trusty1
[deb_ffmpeg.git] / ffmpeg / libavfilter / vf_blackdetect.c
CommitLineData
2ba45a60
DM
1/*
2 * Copyright (c) 2012 Stefano Sabatini
3 *
4 * This file is part of FFmpeg.
5 *
6 * FFmpeg is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2.1 of the License, or (at your option) any later version.
10 *
11 * FFmpeg is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Lesser General Public License for more details.
15 *
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with FFmpeg; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19 */
20
21/**
22 * @file
23 * Video black detector, loosely based on blackframe with extended
24 * syntax and features
25 */
26
27#include <float.h>
28#include "libavutil/opt.h"
29#include "libavutil/timestamp.h"
30#include "avfilter.h"
31#include "internal.h"
32
33typedef struct {
34 const AVClass *class;
35 double black_min_duration_time; ///< minimum duration of detected black, in seconds
36 int64_t black_min_duration; ///< minimum duration of detected black, expressed in timebase units
37 int64_t black_start; ///< pts start time of the first black picture
38 int64_t black_end; ///< pts end time of the last black picture
39 int64_t last_picref_pts; ///< pts of the last input picture
40 int black_started;
41
42 double picture_black_ratio_th;
43 double pixel_black_th;
44 unsigned int pixel_black_th_i;
45
46 unsigned int nb_black_pixels; ///< number of black pixels counted so far
47} BlackDetectContext;
48
49#define OFFSET(x) offsetof(BlackDetectContext, x)
50#define FLAGS AV_OPT_FLAG_VIDEO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
51
52static const AVOption blackdetect_options[] = {
53 { "d", "set minimum detected black duration in seconds", OFFSET(black_min_duration_time), AV_OPT_TYPE_DOUBLE, {.dbl=2}, 0, DBL_MAX, FLAGS },
54 { "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 },
55 { "picture_black_ratio_th", "set the picture black ratio threshold", OFFSET(picture_black_ratio_th), AV_OPT_TYPE_DOUBLE, {.dbl=.98}, 0, 1, FLAGS },
56 { "pic_th", "set the picture black ratio threshold", OFFSET(picture_black_ratio_th), AV_OPT_TYPE_DOUBLE, {.dbl=.98}, 0, 1, FLAGS },
57 { "pixel_black_th", "set the pixel black threshold", OFFSET(pixel_black_th), AV_OPT_TYPE_DOUBLE, {.dbl=.10}, 0, 1, FLAGS },
58 { "pix_th", "set the pixel black threshold", OFFSET(pixel_black_th), AV_OPT_TYPE_DOUBLE, {.dbl=.10}, 0, 1, FLAGS },
59 { NULL }
60};
61
62AVFILTER_DEFINE_CLASS(blackdetect);
63
64#define YUVJ_FORMATS \
65 AV_PIX_FMT_YUVJ411P, AV_PIX_FMT_YUVJ420P, AV_PIX_FMT_YUVJ422P, AV_PIX_FMT_YUVJ444P, AV_PIX_FMT_YUVJ440P
66
67static const enum AVPixelFormat yuvj_formats[] = {
68 YUVJ_FORMATS, AV_PIX_FMT_NONE
69};
70
71static int query_formats(AVFilterContext *ctx)
72{
73 static const enum AVPixelFormat pix_fmts[] = {
74 AV_PIX_FMT_GRAY8,
75 AV_PIX_FMT_YUV410P, AV_PIX_FMT_YUV411P,
76 AV_PIX_FMT_YUV420P, AV_PIX_FMT_YUV422P,
77 AV_PIX_FMT_YUV440P, AV_PIX_FMT_YUV444P,
78 AV_PIX_FMT_NV12, AV_PIX_FMT_NV21,
79 YUVJ_FORMATS,
80 AV_PIX_FMT_NONE
81 };
82
83 ff_set_common_formats(ctx, ff_make_format_list(pix_fmts));
84 return 0;
85}
86
87static int config_input(AVFilterLink *inlink)
88{
89 AVFilterContext *ctx = inlink->dst;
90 BlackDetectContext *blackdetect = ctx->priv;
91
92 blackdetect->black_min_duration =
93 blackdetect->black_min_duration_time / av_q2d(inlink->time_base);
94
95 blackdetect->pixel_black_th_i = ff_fmt_is_in(inlink->format, yuvj_formats) ?
96 // luminance_minimum_value + pixel_black_th * luminance_range_size
97 blackdetect->pixel_black_th * 255 :
98 16 + blackdetect->pixel_black_th * (235 - 16);
99
100 av_log(blackdetect, AV_LOG_VERBOSE,
101 "black_min_duration:%s pixel_black_th:%f pixel_black_th_i:%d picture_black_ratio_th:%f\n",
102 av_ts2timestr(blackdetect->black_min_duration, &inlink->time_base),
103 blackdetect->pixel_black_th, blackdetect->pixel_black_th_i,
104 blackdetect->picture_black_ratio_th);
105 return 0;
106}
107
108static void check_black_end(AVFilterContext *ctx)
109{
110 BlackDetectContext *blackdetect = ctx->priv;
111 AVFilterLink *inlink = ctx->inputs[0];
112
113 if ((blackdetect->black_end - blackdetect->black_start) >= blackdetect->black_min_duration) {
114 av_log(blackdetect, AV_LOG_INFO,
115 "black_start:%s black_end:%s black_duration:%s\n",
116 av_ts2timestr(blackdetect->black_start, &inlink->time_base),
117 av_ts2timestr(blackdetect->black_end, &inlink->time_base),
118 av_ts2timestr(blackdetect->black_end - blackdetect->black_start, &inlink->time_base));
119 }
120}
121
122static int request_frame(AVFilterLink *outlink)
123{
124 AVFilterContext *ctx = outlink->src;
125 BlackDetectContext *blackdetect = ctx->priv;
126 AVFilterLink *inlink = ctx->inputs[0];
127 int ret = ff_request_frame(inlink);
128
129 if (ret == AVERROR_EOF && blackdetect->black_started) {
130 // FIXME: black_end should be set to last_picref_pts + last_picref_duration
131 blackdetect->black_end = blackdetect->last_picref_pts;
132 check_black_end(ctx);
133 }
134 return ret;
135}
136
137// TODO: document metadata
138static int filter_frame(AVFilterLink *inlink, AVFrame *picref)
139{
140 AVFilterContext *ctx = inlink->dst;
141 BlackDetectContext *blackdetect = ctx->priv;
142 double picture_black_ratio = 0;
143 const uint8_t *p = picref->data[0];
144 int x, i;
145
146 for (i = 0; i < inlink->h; i++) {
147 for (x = 0; x < inlink->w; x++)
148 blackdetect->nb_black_pixels += p[x] <= blackdetect->pixel_black_th_i;
149 p += picref->linesize[0];
150 }
151
152 picture_black_ratio = (double)blackdetect->nb_black_pixels / (inlink->w * inlink->h);
153
154 av_log(ctx, AV_LOG_DEBUG,
155 "frame:%"PRId64" picture_black_ratio:%f pts:%s t:%s type:%c\n",
156 inlink->frame_count, picture_black_ratio,
157 av_ts2str(picref->pts), av_ts2timestr(picref->pts, &inlink->time_base),
158 av_get_picture_type_char(picref->pict_type));
159
160 if (picture_black_ratio >= blackdetect->picture_black_ratio_th) {
161 if (!blackdetect->black_started) {
162 /* black starts here */
163 blackdetect->black_started = 1;
164 blackdetect->black_start = picref->pts;
165 av_dict_set(avpriv_frame_get_metadatap(picref), "lavfi.black_start",
166 av_ts2timestr(blackdetect->black_start, &inlink->time_base), 0);
167 }
168 } else if (blackdetect->black_started) {
169 /* black ends here */
170 blackdetect->black_started = 0;
171 blackdetect->black_end = picref->pts;
172 check_black_end(ctx);
173 av_dict_set(avpriv_frame_get_metadatap(picref), "lavfi.black_end",
174 av_ts2timestr(blackdetect->black_end, &inlink->time_base), 0);
175 }
176
177 blackdetect->last_picref_pts = picref->pts;
178 blackdetect->nb_black_pixels = 0;
179 return ff_filter_frame(inlink->dst->outputs[0], picref);
180}
181
182static const AVFilterPad blackdetect_inputs[] = {
183 {
184 .name = "default",
185 .type = AVMEDIA_TYPE_VIDEO,
186 .config_props = config_input,
187 .filter_frame = filter_frame,
188 },
189 { NULL }
190};
191
192static const AVFilterPad blackdetect_outputs[] = {
193 {
194 .name = "default",
195 .type = AVMEDIA_TYPE_VIDEO,
196 .request_frame = request_frame,
197 },
198 { NULL }
199};
200
201AVFilter ff_vf_blackdetect = {
202 .name = "blackdetect",
203 .description = NULL_IF_CONFIG_SMALL("Detect video intervals that are (almost) black."),
204 .priv_size = sizeof(BlackDetectContext),
205 .query_formats = query_formats,
206 .inputs = blackdetect_inputs,
207 .outputs = blackdetect_outputs,
208 .priv_class = &blackdetect_class,
209};