GCC Code Coverage Report
Directory: ../../../ffmpeg/ Exec Total Coverage
File: src/libavfilter/af_silencedetect.c Lines: 88 110 80.0 %
Date: 2020-09-25 23:16:12 Branches: 40 83 48.2 %

Line Branch Exec Source
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/*
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 * Copyright (c) 2012 Clément Bœsch <u pkh me>
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 *
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 * This file is part of FFmpeg.
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 *
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 * FFmpeg is free software; you can redistribute it and/or
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 * modify it under the terms of the GNU Lesser General Public
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 * License as published by the Free Software Foundation; either
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 * version 2.1 of the License, or (at your option) any later version.
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 *
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 * FFmpeg is distributed in the hope that it will be useful,
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 * but WITHOUT ANY WARRANTY; without even the implied warranty of
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 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
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 * Lesser General Public License for more details.
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 *
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 * You should have received a copy of the GNU Lesser General Public
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 * License along with FFmpeg; if not, write to the Free Software
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 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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 */
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/**
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 * @file
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 * Audio silence detector
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 */
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#include <float.h> /* DBL_MAX */
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#include "libavutil/opt.h"
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#include "libavutil/timestamp.h"
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#include "audio.h"
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#include "formats.h"
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#include "avfilter.h"
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#include "internal.h"
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typedef struct SilenceDetectContext {
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    const AVClass *class;
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    double noise;               ///< noise amplitude ratio
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    int64_t duration;           ///< minimum duration of silence until notification
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    int mono;                   ///< mono mode : check each channel separately (default = check when ALL channels are silent)
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    int channels;               ///< number of channels
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    int independent_channels;   ///< number of entries in following arrays (always 1 in mono mode)
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    int64_t *nb_null_samples;   ///< (array) current number of continuous zero samples
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    int64_t *start;             ///< (array) if silence is detected, this value contains the time of the first zero sample (default/unset = INT64_MIN)
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    int64_t frame_end;          ///< pts of the end of the current frame (used to compute duration of silence at EOS)
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    int last_sample_rate;       ///< last sample rate to check for sample rate changes
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    AVRational time_base;       ///< time_base
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    void (*silencedetect)(struct SilenceDetectContext *s, AVFrame *insamples,
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                          int nb_samples, int64_t nb_samples_notify,
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                          AVRational time_base);
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} SilenceDetectContext;
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#define MAX_DURATION (24*3600*1000000LL)
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#define OFFSET(x) offsetof(SilenceDetectContext, x)
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#define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_AUDIO_PARAM
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static const AVOption silencedetect_options[] = {
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    { "n",         "set noise tolerance",              OFFSET(noise),     AV_OPT_TYPE_DOUBLE, {.dbl=0.001},          0, DBL_MAX,  FLAGS },
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    { "noise",     "set noise tolerance",              OFFSET(noise),     AV_OPT_TYPE_DOUBLE, {.dbl=0.001},          0, DBL_MAX,  FLAGS },
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    { "d",         "set minimum duration in seconds",  OFFSET(duration),  AV_OPT_TYPE_DURATION, {.i64=2000000},      0, MAX_DURATION,FLAGS },
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    { "duration",  "set minimum duration in seconds",  OFFSET(duration),  AV_OPT_TYPE_DURATION, {.i64=2000000},      0, MAX_DURATION,FLAGS },
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    { "mono",      "check each channel separately",    OFFSET(mono),      AV_OPT_TYPE_BOOL,   {.i64=0},              0, 1,        FLAGS },
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    { "m",         "check each channel separately",    OFFSET(mono),      AV_OPT_TYPE_BOOL,   {.i64=0},              0, 1,        FLAGS },
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    { NULL }
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};
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AVFILTER_DEFINE_CLASS(silencedetect);
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static void set_meta(AVFrame *insamples, int channel, const char *key, char *value)
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{
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    char key2[128];
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    if (channel)
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        snprintf(key2, sizeof(key2), "lavfi.%s.%d", key, channel);
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    else
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9
        snprintf(key2, sizeof(key2), "lavfi.%s", key);
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    av_dict_set(&insamples->metadata, key2, value, 0);
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}
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1048554
static av_always_inline void update(SilenceDetectContext *s, AVFrame *insamples,
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                                    int is_silence, int current_sample, int64_t nb_samples_notify,
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                                    AVRational time_base)
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{
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1048554
    int channel = current_sample % s->independent_channels;
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1048554
    if (is_silence) {
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304774
        if (s->start[channel] == INT64_MIN) {
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221400
            s->nb_null_samples[channel]++;
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221400
            if (s->nb_null_samples[channel] >= nb_samples_notify) {
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3
                s->start[channel] = insamples->pts + av_rescale_q(current_sample / s->channels + 1 - nb_samples_notify * s->independent_channels / s->channels,
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                        (AVRational){ 1, s->last_sample_rate }, time_base);
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                set_meta(insamples, s->mono ? channel + 1 : 0, "silence_start",
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                        av_ts2timestr(s->start[channel], &time_base));
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                if (s->mono)
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                    av_log(s, AV_LOG_INFO, "channel: %d | ", channel);
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                av_log(s, AV_LOG_INFO, "silence_start: %s\n",
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                        av_ts2timestr(s->start[channel], &time_base));
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            }
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        }
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    } else {
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743780
        if (s->start[channel] > INT64_MIN) {
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            int64_t end_pts = insamples ? insamples->pts + av_rescale_q(current_sample / s->channels,
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                    (AVRational){ 1, s->last_sample_rate }, time_base)
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                    : s->frame_end;
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3
            int64_t duration_ts = end_pts - s->start[channel];
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3
            if (insamples) {
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                set_meta(insamples, s->mono ? channel + 1 : 0, "silence_end",
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                        av_ts2timestr(end_pts, &time_base));
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                set_meta(insamples, s->mono ? channel + 1 : 0, "silence_duration",
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                        av_ts2timestr(duration_ts, &time_base));
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            }
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            if (s->mono)
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                av_log(s, AV_LOG_INFO, "channel: %d | ", channel);
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            av_log(s, AV_LOG_INFO, "silence_end: %s | silence_duration: %s\n",
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                    av_ts2timestr(end_pts, &time_base),
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                    av_ts2timestr(duration_ts, &time_base));
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        }
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        s->nb_null_samples[channel] = 0;
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        s->start[channel] = INT64_MIN;
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    }
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1048554
}
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#define SILENCE_DETECT(name, type)                                               \
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static void silencedetect_##name(SilenceDetectContext *s, AVFrame *insamples,    \
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                                 int nb_samples, int64_t nb_samples_notify,      \
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                                 AVRational time_base)                           \
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{                                                                                \
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    const type *p = (const type *)insamples->data[0];                            \
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    const type noise = s->noise;                                                 \
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    int i;                                                                       \
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                                                                                 \
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    for (i = 0; i < nb_samples; i++, p++)                                        \
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        update(s, insamples, *p < noise && *p > -noise, i,                       \
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               nb_samples_notify, time_base);                                    \
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}
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SILENCE_DETECT(dbl, double)
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SILENCE_DETECT(flt, float)
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SILENCE_DETECT(s32, int32_t)
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SILENCE_DETECT(s16, int16_t)
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static int config_input(AVFilterLink *inlink)
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{
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1
    AVFilterContext *ctx = inlink->dst;
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1
    SilenceDetectContext *s = ctx->priv;
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    int c;
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    s->channels = inlink->channels;
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1
    s->duration = av_rescale(s->duration, inlink->sample_rate, AV_TIME_BASE);
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1
    s->independent_channels = s->mono ? s->channels : 1;
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1
    s->nb_null_samples = av_mallocz_array(sizeof(*s->nb_null_samples), s->independent_channels);
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1
    if (!s->nb_null_samples)
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        return AVERROR(ENOMEM);
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1
    s->start = av_malloc_array(sizeof(*s->start), s->independent_channels);
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1
    if (!s->start)
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        return AVERROR(ENOMEM);
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    for (c = 0; c < s->independent_channels; c++)
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1
        s->start[c] = INT64_MIN;
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    switch (inlink->format) {
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    case AV_SAMPLE_FMT_DBL: s->silencedetect = silencedetect_dbl; break;
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    case AV_SAMPLE_FMT_FLT: s->silencedetect = silencedetect_flt; break;
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    case AV_SAMPLE_FMT_S32:
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        s->noise *= INT32_MAX;
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        s->silencedetect = silencedetect_s32;
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        break;
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    case AV_SAMPLE_FMT_S16:
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1
        s->noise *= INT16_MAX;
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        s->silencedetect = silencedetect_s16;
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1
        break;
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    }
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    return 0;
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}
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static int filter_frame(AVFilterLink *inlink, AVFrame *insamples)
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{
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    SilenceDetectContext *s         = inlink->dst->priv;
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    const int nb_channels           = inlink->channels;
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    const int srate                 = inlink->sample_rate;
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    const int nb_samples            = insamples->nb_samples     * nb_channels;
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    const int64_t nb_samples_notify = s->duration * (s->mono ? 1 : nb_channels);
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    int c;
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    // scale number of null samples to the new sample rate
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    if (s->last_sample_rate && s->last_sample_rate != srate)
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        for (c = 0; c < s->independent_channels; c++) {
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            s->nb_null_samples[c] = srate * s->nb_null_samples[c] / s->last_sample_rate;
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        }
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    s->last_sample_rate = srate;
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    s->time_base = inlink->time_base;
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    s->frame_end = insamples->pts + av_rescale_q(insamples->nb_samples,
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            (AVRational){ 1, s->last_sample_rate }, inlink->time_base);
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    s->silencedetect(s, insamples, nb_samples, nb_samples_notify,
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                     inlink->time_base);
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    return ff_filter_frame(inlink->dst->outputs[0], insamples);
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}
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static int query_formats(AVFilterContext *ctx)
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{
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1
    AVFilterFormats *formats = NULL;
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1
    AVFilterChannelLayouts *layouts = NULL;
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    static const enum AVSampleFormat sample_fmts[] = {
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        AV_SAMPLE_FMT_DBL,
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        AV_SAMPLE_FMT_FLT,
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        AV_SAMPLE_FMT_S32,
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        AV_SAMPLE_FMT_S16,
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        AV_SAMPLE_FMT_NONE
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    };
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    int ret;
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    layouts = ff_all_channel_layouts();
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1
    if (!layouts)
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        return AVERROR(ENOMEM);
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1
    ret = ff_set_common_channel_layouts(ctx, layouts);
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1
    if (ret < 0)
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        return ret;
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    formats = ff_make_format_list(sample_fmts);
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    if (!formats)
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        return AVERROR(ENOMEM);
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    ret = ff_set_common_formats(ctx, formats);
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1
    if (ret < 0)
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        return ret;
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    formats = ff_all_samplerates();
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1
    if (!formats)
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        return AVERROR(ENOMEM);
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    return ff_set_common_samplerates(ctx, formats);
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}
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static av_cold void uninit(AVFilterContext *ctx)
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{
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    SilenceDetectContext *s = ctx->priv;
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    int c;
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    for (c = 0; c < s->independent_channels; c++)
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1
        if (s->start[c] > INT64_MIN)
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            update(s, NULL, 0, c, 0, s->time_base);
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1
    av_freep(&s->nb_null_samples);
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1
    av_freep(&s->start);
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1
}
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static const AVFilterPad silencedetect_inputs[] = {
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    {
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        .name         = "default",
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        .type         = AVMEDIA_TYPE_AUDIO,
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        .config_props = config_input,
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        .filter_frame = filter_frame,
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    },
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    { NULL }
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};
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static const AVFilterPad silencedetect_outputs[] = {
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    {
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        .name = "default",
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        .type = AVMEDIA_TYPE_AUDIO,
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    },
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    { NULL }
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};
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AVFilter ff_af_silencedetect = {
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    .name          = "silencedetect",
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    .description   = NULL_IF_CONFIG_SMALL("Detect silence."),
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    .priv_size     = sizeof(SilenceDetectContext),
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    .query_formats = query_formats,
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    .uninit        = uninit,
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    .inputs        = silencedetect_inputs,
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    .outputs       = silencedetect_outputs,
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    .priv_class    = &silencedetect_class,
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};