1
0
mirror of https://github.com/FFmpeg/FFmpeg.git synced 2024-12-07 11:13:41 +02:00
FFmpeg/libavfilter/af_silencedetect.c
Andreas Rheinhardt 790f793844 avutil/common: Don't auto-include mem.h
There are lots of files that don't need it: The number of object
files that actually need it went down from 2011 to 884 here.

Keep it for external users in order to not cause breakages.

Also improve the other headers a bit while just at it.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
2024-03-31 00:08:43 +01:00

270 lines
12 KiB
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/mem.h"
#include "libavutil/opt.h"
#include "libavutil/timestamp.h"
#include "audio.h"
#include "avfilter.h"
#include "internal.h"
typedef struct SilenceDetectContext {
const AVClass *class;
double noise; ///< noise amplitude ratio
int64_t duration; ///< minimum duration of silence until notification
int mono; ///< mono mode : check each channel separately (default = check when ALL channels are silent)
int channels; ///< number of channels
int independent_channels; ///< number of entries in following arrays (always 1 in mono mode)
int64_t *nb_null_samples; ///< (array) current number of continuous zero samples
int64_t *start; ///< (array) if silence is detected, this value contains the time of the first zero sample (default/unset = INT64_MIN)
int64_t frame_end; ///< pts of the end of the current frame (used to compute duration of silence at EOS)
int last_sample_rate; ///< last sample rate to check for sample rate changes
AVRational time_base; ///< time_base
void (*silencedetect)(struct SilenceDetectContext *s, AVFrame *insamples,
int nb_samples, int64_t nb_samples_notify,
AVRational time_base);
} SilenceDetectContext;
#define MAX_DURATION (24*3600*1000000LL)
#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_DURATION, {.i64=2000000}, 0, MAX_DURATION,FLAGS },
{ "duration", "set minimum duration in seconds", OFFSET(duration), AV_OPT_TYPE_DURATION, {.i64=2000000}, 0, MAX_DURATION,FLAGS },
{ "mono", "check each channel separately", OFFSET(mono), AV_OPT_TYPE_BOOL, {.i64=0}, 0, 1, FLAGS },
{ "m", "check each channel separately", OFFSET(mono), AV_OPT_TYPE_BOOL, {.i64=0}, 0, 1, FLAGS },
{ NULL }
};
AVFILTER_DEFINE_CLASS(silencedetect);
static void set_meta(AVFrame *insamples, int channel, const char *key, char *value)
{
char key2[128];
if (channel)
snprintf(key2, sizeof(key2), "lavfi.%s.%d", key, channel);
else
snprintf(key2, sizeof(key2), "lavfi.%s", key);
av_dict_set(&insamples->metadata, key2, value, 0);
}
static av_always_inline void update(SilenceDetectContext *s, AVFrame *insamples,
int is_silence, int current_sample, int64_t nb_samples_notify,
AVRational time_base)
{
int channel = current_sample % s->independent_channels;
if (is_silence) {
if (s->start[channel] == INT64_MIN) {
s->nb_null_samples[channel]++;
if (s->nb_null_samples[channel] >= nb_samples_notify) {
s->start[channel] = insamples->pts + av_rescale_q(current_sample / s->channels + 1 - nb_samples_notify * s->independent_channels / s->channels,
(AVRational){ 1, s->last_sample_rate }, time_base);
set_meta(insamples, s->mono ? channel + 1 : 0, "silence_start",
av_ts2timestr(s->start[channel], &time_base));
if (s->mono)
av_log(s, AV_LOG_INFO, "channel: %d | ", channel);
av_log(s, AV_LOG_INFO, "silence_start: %s\n",
av_ts2timestr(s->start[channel], &time_base));
}
}
} else {
if (s->start[channel] > INT64_MIN) {
int64_t end_pts = insamples ? insamples->pts + av_rescale_q(current_sample / s->channels,
(AVRational){ 1, s->last_sample_rate }, time_base)
: s->frame_end;
int64_t duration_ts = end_pts - s->start[channel];
if (insamples) {
set_meta(insamples, s->mono ? channel + 1 : 0, "silence_end",
av_ts2timestr(end_pts, &time_base));
set_meta(insamples, s->mono ? channel + 1 : 0, "silence_duration",
av_ts2timestr(duration_ts, &time_base));
}
if (s->mono)
av_log(s, AV_LOG_INFO, "channel: %d | ", channel);
av_log(s, AV_LOG_INFO, "silence_end: %s | silence_duration: %s\n",
av_ts2timestr(end_pts, &time_base),
av_ts2timestr(duration_ts, &time_base));
}
s->nb_null_samples[channel] = 0;
s->start[channel] = INT64_MIN;
}
}
#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, i, \
nb_samples_notify, time_base); \
}
#define SILENCE_DETECT_PLANAR(name, type) \
static void silencedetect_##name(SilenceDetectContext *s, AVFrame *insamples, \
int nb_samples, int64_t nb_samples_notify, \
AVRational time_base) \
{ \
const int channels = insamples->ch_layout.nb_channels; \
const type noise = s->noise; \
\
nb_samples /= channels; \
for (int i = 0; i < nb_samples; i++) { \
for (int ch = 0; ch < insamples->ch_layout.nb_channels; ch++) { \
const type *p = (const type *)insamples->extended_data[ch]; \
update(s, insamples, p[i] < noise && p[i] > -noise, \
channels * i + ch, \
nb_samples_notify, time_base); \
} \
} \
}
SILENCE_DETECT(dbl, double)
SILENCE_DETECT(flt, float)
SILENCE_DETECT(s32, int32_t)
SILENCE_DETECT(s16, int16_t)
SILENCE_DETECT_PLANAR(dblp, double)
SILENCE_DETECT_PLANAR(fltp, float)
SILENCE_DETECT_PLANAR(s32p, int32_t)
SILENCE_DETECT_PLANAR(s16p, int16_t)
static int config_input(AVFilterLink *inlink)
{
AVFilterContext *ctx = inlink->dst;
SilenceDetectContext *s = ctx->priv;
int c;
s->channels = inlink->ch_layout.nb_channels;
s->duration = av_rescale(s->duration, inlink->sample_rate, AV_TIME_BASE);
s->independent_channels = s->mono ? s->channels : 1;
s->nb_null_samples = av_calloc(s->independent_channels,
sizeof(*s->nb_null_samples));
if (!s->nb_null_samples)
return AVERROR(ENOMEM);
s->start = av_malloc_array(sizeof(*s->start), s->independent_channels);
if (!s->start)
return AVERROR(ENOMEM);
for (c = 0; c < s->independent_channels; c++)
s->start[c] = INT64_MIN;
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;
case AV_SAMPLE_FMT_DBLP: s->silencedetect = silencedetect_dblp; break;
case AV_SAMPLE_FMT_FLTP: s->silencedetect = silencedetect_fltp; break;
case AV_SAMPLE_FMT_S32P:
s->noise *= INT32_MAX;
s->silencedetect = silencedetect_s32p;
break;
case AV_SAMPLE_FMT_S16P:
s->noise *= INT16_MAX;
s->silencedetect = silencedetect_s16p;
break;
default:
return AVERROR_BUG;
}
return 0;
}
static int filter_frame(AVFilterLink *inlink, AVFrame *insamples)
{
SilenceDetectContext *s = inlink->dst->priv;
const int nb_channels = inlink->ch_layout.nb_channels;
const int srate = inlink->sample_rate;
const int nb_samples = insamples->nb_samples * nb_channels;
const int64_t nb_samples_notify = s->duration * (s->mono ? 1 : nb_channels);
int c;
// scale number of null samples to the new sample rate
if (s->last_sample_rate && s->last_sample_rate != srate)
for (c = 0; c < s->independent_channels; c++) {
s->nb_null_samples[c] = srate * s->nb_null_samples[c] / s->last_sample_rate;
}
s->last_sample_rate = srate;
s->time_base = inlink->time_base;
s->frame_end = insamples->pts + av_rescale_q(insamples->nb_samples,
(AVRational){ 1, s->last_sample_rate }, inlink->time_base);
s->silencedetect(s, insamples, nb_samples, nb_samples_notify,
inlink->time_base);
return ff_filter_frame(inlink->dst->outputs[0], insamples);
}
static av_cold void uninit(AVFilterContext *ctx)
{
SilenceDetectContext *s = ctx->priv;
int c;
for (c = 0; c < s->independent_channels; c++)
if (s->start[c] > INT64_MIN)
update(s, NULL, 0, c, 0, s->time_base);
av_freep(&s->nb_null_samples);
av_freep(&s->start);
}
static const AVFilterPad silencedetect_inputs[] = {
{
.name = "default",
.type = AVMEDIA_TYPE_AUDIO,
.config_props = config_input,
.filter_frame = filter_frame,
},
};
const AVFilter ff_af_silencedetect = {
.name = "silencedetect",
.description = NULL_IF_CONFIG_SMALL("Detect silence."),
.priv_size = sizeof(SilenceDetectContext),
.uninit = uninit,
FILTER_INPUTS(silencedetect_inputs),
FILTER_OUTPUTS(ff_audio_default_filterpad),
FILTER_SAMPLEFMTS(AV_SAMPLE_FMT_DBL, AV_SAMPLE_FMT_DBLP,
AV_SAMPLE_FMT_FLT, AV_SAMPLE_FMT_FLTP,
AV_SAMPLE_FMT_S32, AV_SAMPLE_FMT_S32P,
AV_SAMPLE_FMT_S16, AV_SAMPLE_FMT_S16P),
.priv_class = &silencedetect_class,
.flags = AVFILTER_FLAG_METADATA_ONLY,
};