[deb_ffmpeg.git] / ffmpeg / libavfilter / af_silencedetect.c

/*
 * Copyright (c) 2012 Clément Bœsch <u pkh me>
 *
 * 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
 * Audio silence detector
 */

#include <float.h> /* DBL_MAX */

#include "libavutil/opt.h"
#include "libavutil/timestamp.h"
#include "audio.h"
#include "formats.h"
#include "avfilter.h"
#include "internal.h"

typedef struct SilenceDetectContext {
    const AVClass *class;
    double noise;               ///< noise amplitude ratio
    double duration;            ///< minimum duration of silence until notification
    int64_t nb_null_samples;    ///< current number of continuous zero samples
    int64_t start;              ///< if silence is detected, this value contains the time of the first zero sample
    int last_sample_rate;       ///< last sample rate to check for sample rate changes

    void (*silencedetect)(struct SilenceDetectContext *s, AVFrame *insamples,
                          int nb_samples, int64_t nb_samples_notify,
                          AVRational time_base);
} SilenceDetectContext;

#define OFFSET(x) offsetof(SilenceDetectContext, x)
#define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_AUDIO_PARAM
static const AVOption silencedetect_options[] = {
    { "n",         "set noise tolerance",              OFFSET(noise),     AV_OPT_TYPE_DOUBLE, {.dbl=0.001},          0, DBL_MAX,  FLAGS },
    { "noise",     "set noise tolerance",              OFFSET(noise),     AV_OPT_TYPE_DOUBLE, {.dbl=0.001},          0, DBL_MAX,  FLAGS },
    { "d",         "set minimum duration in seconds",  OFFSET(duration),  AV_OPT_TYPE_DOUBLE, {.dbl=2.},             0, 24*60*60, FLAGS },
    { "duration",  "set minimum duration in seconds",  OFFSET(duration),  AV_OPT_TYPE_DOUBLE, {.dbl=2.},             0, 24*60*60, FLAGS },
    { NULL }
};

AVFILTER_DEFINE_CLASS(silencedetect);

static char *get_metadata_val(AVFrame *insamples, const char *key)
{
    AVDictionaryEntry *e = av_dict_get(insamples->metadata, key, NULL, 0);
    return e && e->value ? e->value : NULL;
}

static av_always_inline void update(SilenceDetectContext *s, AVFrame *insamples,
                                    int is_silence, int64_t nb_samples_notify,
                                    AVRational time_base)
{
    if (is_silence) {
        if (!s->start) {
            s->nb_null_samples++;
            if (s->nb_null_samples >= nb_samples_notify) {
                s->start = insamples->pts - (int64_t)(s->duration / av_q2d(time_base) + .5);
                av_dict_set(&insamples->metadata, "lavfi.silence_start",
                            av_ts2timestr(s->start, &time_base), 0);
                av_log(s, AV_LOG_INFO, "silence_start: %s\n",
                       get_metadata_val(insamples, "lavfi.silence_start"));
            }
        }
    } else {
        if (s->start) {
            av_dict_set(&insamples->metadata, "lavfi.silence_end",
                        av_ts2timestr(insamples->pts, &time_base), 0);
            av_dict_set(&insamples->metadata, "lavfi.silence_duration",
                        av_ts2timestr(insamples->pts - s->start, &time_base), 0);
            av_log(s, AV_LOG_INFO,
                   "silence_end: %s | silence_duration: %s\n",
                   get_metadata_val(insamples, "lavfi.silence_end"),
                   get_metadata_val(insamples, "lavfi.silence_duration"));
        }
        s->nb_null_samples = s->start = 0;
    }
}

#define SILENCE_DETECT(name, type)                                               \
static void silencedetect_##name(SilenceDetectContext *s, AVFrame *insamples,    \
                                 int nb_samples, int64_t nb_samples_notify,      \
                                 AVRational time_base)                           \
{                                                                                \
    const type *p = (const type *)insamples->data[0];                            \
    const type noise = s->noise;                                                 \
    int i;                                                                       \
                                                                                 \
    for (i = 0; i < nb_samples; i++, p++)                                        \
        update(s, insamples, *p < noise && *p > -noise,                          \
               nb_samples_notify, time_base);                                    \
}

SILENCE_DETECT(dbl, double)
SILENCE_DETECT(flt, float)
SILENCE_DETECT(s32, int32_t)
SILENCE_DETECT(s16, int16_t)

static int config_input(AVFilterLink *inlink)
{
    AVFilterContext *ctx = inlink->dst;
    SilenceDetectContext *s = ctx->priv;

    switch (inlink->format) {
    case AV_SAMPLE_FMT_DBL: s->silencedetect = silencedetect_dbl; break;
    case AV_SAMPLE_FMT_FLT: s->silencedetect = silencedetect_flt; break;
    case AV_SAMPLE_FMT_S32:
        s->noise *= INT32_MAX;
        s->silencedetect = silencedetect_s32;
        break;
    case AV_SAMPLE_FMT_S16:
        s->noise *= INT16_MAX;
        s->silencedetect = silencedetect_s16;
        break;
    }

    return 0;
}

static int filter_frame(AVFilterLink *inlink, AVFrame *insamples)
{
    SilenceDetectContext *s         = inlink->dst->priv;
    const int nb_channels           = inlink->channels;
    const int srate                 = inlink->sample_rate;
    const int nb_samples            = insamples->nb_samples     * nb_channels;
    const int64_t nb_samples_notify = srate * s->duration * nb_channels;

    // scale number of null samples to the new sample rate
    if (s->last_sample_rate && s->last_sample_rate != srate)
        s->nb_null_samples = srate * s->nb_null_samples / s->last_sample_rate;
    s->last_sample_rate = srate;

    // TODO: document metadata
    s->silencedetect(s, insamples, nb_samples, nb_samples_notify,
                     inlink->time_base);

    return ff_filter_frame(inlink->dst->outputs[0], insamples);
}

static int query_formats(AVFilterContext *ctx)
{
    AVFilterFormats *formats = NULL;
    AVFilterChannelLayouts *layouts = NULL;
    static const enum AVSampleFormat sample_fmts[] = {
        AV_SAMPLE_FMT_DBL,
        AV_SAMPLE_FMT_FLT,
        AV_SAMPLE_FMT_S32,
        AV_SAMPLE_FMT_S16,
        AV_SAMPLE_FMT_NONE
    };

    layouts = ff_all_channel_layouts();
    if (!layouts)
        return AVERROR(ENOMEM);
    ff_set_common_channel_layouts(ctx, layouts);

    formats = ff_make_format_list(sample_fmts);
    if (!formats)
        return AVERROR(ENOMEM);
    ff_set_common_formats(ctx, formats);

    formats = ff_all_samplerates();
    if (!formats)
        return AVERROR(ENOMEM);
    ff_set_common_samplerates(ctx, formats);

    return 0;
}

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

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

AVFilter ff_af_silencedetect = {
    .name          = "silencedetect",
    .description   = NULL_IF_CONFIG_SMALL("Detect silence."),
    .priv_size     = sizeof(SilenceDetectContext),
    .query_formats = query_formats,
    .inputs        = silencedetect_inputs,
    .outputs       = silencedetect_outputs,
    .priv_class    = &silencedetect_class,
};
Commit	Line	Data
2ba45a60 DM	1	/*
	2	* Copyright (c) 2012 Clément Bœsch <u pkh me>
	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	* Audio silence detector
	24	*/
	25
	26	#include <float.h> /* DBL_MAX */
	27
	28	#include "libavutil/opt.h"
	29	#include "libavutil/timestamp.h"
	30	#include "audio.h"
	31	#include "formats.h"
	32	#include "avfilter.h"
	33	#include "internal.h"
	34
	35	typedef struct SilenceDetectContext {
	36	const AVClass *class;
	37	double noise; ///< noise amplitude ratio
	38	double duration; ///< minimum duration of silence until notification
	39	int64_t nb_null_samples; ///< current number of continuous zero samples
	40	int64_t start; ///< if silence is detected, this value contains the time of the first zero sample
	41	int last_sample_rate; ///< last sample rate to check for sample rate changes
	42
	43	void (silencedetect)(struct SilenceDetectContext s, AVFrame *insamples,
	44	int nb_samples, int64_t nb_samples_notify,
	45	AVRational time_base);
	46	} SilenceDetectContext;
	47
	48	#define OFFSET(x) offsetof(SilenceDetectContext, x)
	49	#define FLAGS AV_OPT_FLAG_FILTERING_PARAM\|AV_OPT_FLAG_AUDIO_PARAM
	50	static const AVOption silencedetect_options[] = {
	51	{ "n", "set noise tolerance", OFFSET(noise), AV_OPT_TYPE_DOUBLE, {.dbl=0.001}, 0, DBL_MAX, FLAGS },
	52	{ "noise", "set noise tolerance", OFFSET(noise), AV_OPT_TYPE_DOUBLE, {.dbl=0.001}, 0, DBL_MAX, FLAGS },
	53	{ "d", "set minimum duration in seconds", OFFSET(duration), AV_OPT_TYPE_DOUBLE, {.dbl=2.}, 0, 246060, FLAGS },
	54	{ "duration", "set minimum duration in seconds", OFFSET(duration), AV_OPT_TYPE_DOUBLE, {.dbl=2.}, 0, 246060, FLAGS },
	55	{ NULL }
	56	};
	57
	58	AVFILTER_DEFINE_CLASS(silencedetect);
	59
	60	static char get_metadata_val(AVFrame insamples, const char *key)
	61	{
	62	AVDictionaryEntry *e = av_dict_get(insamples->metadata, key, NULL, 0);
	63	return e && e->value ? e->value : NULL;
	64	}
65
66	static av_always_inline void update(SilenceDetectContext s, AVFrame insamples,
67	int is_silence, int64_t nb_samples_notify,
68	AVRational time_base)
69	{
70	if (is_silence) {
71	if (!s->start) {
72	s->nb_null_samples++;
73	if (s->nb_null_samples >= nb_samples_notify) {
74	s->start = insamples->pts - (int64_t)(s->duration / av_q2d(time_base) + .5);
75	av_dict_set(&insamples->metadata, "lavfi.silence_start",
76	av_ts2timestr(s->start, &time_base), 0);
77	av_log(s, AV_LOG_INFO, "silence_start: %s\n",
78	get_metadata_val(insamples, "lavfi.silence_start"));
79	}
80	}
81	} else {
82	if (s->start) {
83	av_dict_set(&insamples->metadata, "lavfi.silence_end",
84	av_ts2timestr(insamples->pts, &time_base), 0);
85	av_dict_set(&insamples->metadata, "lavfi.silence_duration",
86	av_ts2timestr(insamples->pts - s->start, &time_base), 0);
87	av_log(s, AV_LOG_INFO,
88	"silence_end: %s \| silence_duration: %s\n",
89	get_metadata_val(insamples, "lavfi.silence_end"),
90	get_metadata_val(insamples, "lavfi.silence_duration"));
91	}
92	s->nb_null_samples = s->start = 0;
93	}
94	}
95
96	#define SILENCE_DETECT(name, type) \
97	static void silencedetect_##name(SilenceDetectContext s, AVFrame insamples, \
98	int nb_samples, int64_t nb_samples_notify, \
99	AVRational time_base) \
100	{ \
101	const type p = (const type )insamples->data[0]; \
102	const type noise = s->noise; \
103	int i; \
104	\
105	for (i = 0; i < nb_samples; i++, p++) \
106	update(s, insamples, p < noise && p > -noise, \
107	nb_samples_notify, time_base); \
108	}
109
110	SILENCE_DETECT(dbl, double)
111	SILENCE_DETECT(flt, float)
112	SILENCE_DETECT(s32, int32_t)
113	SILENCE_DETECT(s16, int16_t)
114
115	static int config_input(AVFilterLink *inlink)
116	{
117	AVFilterContext *ctx = inlink->dst;
118	SilenceDetectContext *s = ctx->priv;
119
120	switch (inlink->format) {
121	case AV_SAMPLE_FMT_DBL: s->silencedetect = silencedetect_dbl; break;
122	case AV_SAMPLE_FMT_FLT: s->silencedetect = silencedetect_flt; break;
123	case AV_SAMPLE_FMT_S32:
124	s->noise *= INT32_MAX;
125	s->silencedetect = silencedetect_s32;
126	break;
127	case AV_SAMPLE_FMT_S16:
128	s->noise *= INT16_MAX;
129	s->silencedetect = silencedetect_s16;
130	break;
131	}
132
133	return 0;
134	}
135
136	static int filter_frame(AVFilterLink inlink, AVFrame insamples)
137	{
138	SilenceDetectContext *s = inlink->dst->priv;
139	const int nb_channels = inlink->channels;
140	const int srate = inlink->sample_rate;
141	const int nb_samples = insamples->nb_samples * nb_channels;
142	const int64_t nb_samples_notify = srate * s->duration * nb_channels;
143
144	// scale number of null samples to the new sample rate
145	if (s->last_sample_rate && s->last_sample_rate != srate)
146	s->nb_null_samples = srate * s->nb_null_samples / s->last_sample_rate;
147	s->last_sample_rate = srate;
148
149	// TODO: document metadata
150	s->silencedetect(s, insamples, nb_samples, nb_samples_notify,
151	inlink->time_base);
152
153	return ff_filter_frame(inlink->dst->outputs[0], insamples);
154	}
155
156	static int query_formats(AVFilterContext *ctx)
157	{
158	AVFilterFormats *formats = NULL;
159	AVFilterChannelLayouts *layouts = NULL;
160	static const enum AVSampleFormat sample_fmts[] = {
161	AV_SAMPLE_FMT_DBL,
162	AV_SAMPLE_FMT_FLT,
163	AV_SAMPLE_FMT_S32,
164	AV_SAMPLE_FMT_S16,
165	AV_SAMPLE_FMT_NONE
166	};
167
168	layouts = ff_all_channel_layouts();
169	if (!layouts)
170	return AVERROR(ENOMEM);
171	ff_set_common_channel_layouts(ctx, layouts);
172
173	formats = ff_make_format_list(sample_fmts);
174	if (!formats)
175	return AVERROR(ENOMEM);
176	ff_set_common_formats(ctx, formats);
177
178	formats = ff_all_samplerates();
179	if (!formats)
180	return AVERROR(ENOMEM);
181	ff_set_common_samplerates(ctx, formats);
182
183	return 0;
184	}
185
186	static const AVFilterPad silencedetect_inputs[] = {
187	{
188	.name = "default",
189	.type = AVMEDIA_TYPE_AUDIO,
190	.config_props = config_input,
191	.filter_frame = filter_frame,
192	},
193	{ NULL }
194	};
195
196	static const AVFilterPad silencedetect_outputs[] = {
197	{
198	.name = "default",
199	.type = AVMEDIA_TYPE_AUDIO,
200	},
201	{ NULL }
202	};
203
204	AVFilter ff_af_silencedetect = {
205	.name = "silencedetect",
206	.description = NULL_IF_CONFIG_SMALL("Detect silence."),
207	.priv_size = sizeof(SilenceDetectContext),
208	.query_formats = query_formats,
209	.inputs = silencedetect_inputs,
210	.outputs = silencedetect_outputs,
211	.priv_class = &silencedetect_class,
212	};