From 95e47654bce3f76360db2bbd9f34929a3434920a Mon Sep 17 00:00:00 2001 From: Nicolas Gaullier Date: Mon, 19 Feb 2018 14:15:30 +0100 Subject: [PATCH] lavfi/silencedetect: Add mono mode In mono mode, silence is detected in any single channel instead of all of them simultaneously --- libavfilter/af_silencedetect.c | 78 ++++++++++++++++++++++------------ 1 file changed, 51 insertions(+), 27 deletions(-) diff --git a/libavfilter/af_silencedetect.c b/libavfilter/af_silencedetect.c index b048d63738..c53b9d9218 100644 --- a/libavfilter/af_silencedetect.c +++ b/libavfilter/af_silencedetect.c @@ -36,8 +36,10 @@ 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 mono; ///< mono mode : check each channel separately (default = check when ALL channels are silent) + int independant_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 int last_sample_rate; ///< last sample rate to check for sample rate changes void (*silencedetect)(struct SilenceDetectContext *s, AVFrame *insamples, @@ -52,44 +54,55 @@ static const AVOption silencedetect_options[] = { { "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 }, + { "mono", "check each channel separately", OFFSET(mono), AV_OPT_TYPE_BOOL, {.i64=0.}, 0, 1, FLAGS }, { NULL } }; AVFILTER_DEFINE_CLASS(silencedetect); -static char *get_metadata_val(AVFrame *insamples, const char *key) +static void set_meta(AVFrame *insamples, int channel, const char *key, char *value) { - AVDictionaryEntry *e = av_dict_get(insamples->metadata, key, NULL, 0); - return e && e->value ? e->value : NULL; -} + 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, int64_t nb_samples_notify, + int is_silence, int current_sample, int64_t nb_samples_notify, AVRational time_base) { + int channel = current_sample % s->independant_channels; 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); + if (!s->start[channel]) { + s->nb_null_samples[channel]++; + if (s->nb_null_samples[channel] >= nb_samples_notify) { + s->start[channel] = insamples->pts - (int64_t)(s->duration / av_q2d(time_base) + .5); + 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", - get_metadata_val(insamples, "lavfi.silence_start")); + av_ts2timestr(s->start[channel], &time_base)); } } } 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")); + if (s->start[channel]) { + int64_t end_pts = insamples->pts; + int64_t duration_ts = end_pts - s->start[channel]; + 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 = s->start = 0; + s->nb_null_samples[channel] = s->start[channel] = 0; } } @@ -103,7 +116,7 @@ static void silencedetect_##name(SilenceDetectContext *s, AVFrame *insamples, int i; \ \ for (i = 0; i < nb_samples; i++, p++) \ - update(s, insamples, *p < noise && *p > -noise, \ + update(s, insamples, *p < noise && *p > -noise, i, \ nb_samples_notify, time_base); \ } @@ -117,6 +130,14 @@ static int config_input(AVFilterLink *inlink) AVFilterContext *ctx = inlink->dst; SilenceDetectContext *s = ctx->priv; + s->independant_channels = s->mono ? inlink->channels : 1; + s->nb_null_samples = av_mallocz_array(sizeof(*s->nb_null_samples), s->independant_channels); + if (!s->nb_null_samples) + return AVERROR(ENOMEM); + s->start = av_mallocz_array(sizeof(*s->start), s->independant_channels); + if (!s->start) + return AVERROR(ENOMEM); + switch (inlink->format) { case AV_SAMPLE_FMT_DBL: s->silencedetect = silencedetect_dbl; break; case AV_SAMPLE_FMT_FLT: s->silencedetect = silencedetect_flt; break; @@ -139,11 +160,14 @@ static int filter_frame(AVFilterLink *inlink, AVFrame *insamples) 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; + const int64_t nb_samples_notify = srate * 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) - s->nb_null_samples = srate * s->nb_null_samples / s->last_sample_rate; + for (c = 0; c < s->independant_channels; c++) { + s->nb_null_samples[c] = srate * s->nb_null_samples[c] / s->last_sample_rate; + } s->last_sample_rate = srate; // TODO: document metadata