[Libav-user] Audio silence detector avfilter

[Сергей Икол]

Hello everybody!
I need help solving my problem.

I wanted to make a C++ implementation of the Audio silence detector. I used
the example from github (
https://github.com/FFmpeg/FFmpeg/blob/master/libavfilter/af_silencedetect.c).
I have also simplified this example to the following form.
const int nb_samples = this->frame->nb_samples * nb_channels;
const int64_t nb_samples_notify = this->srate * silence->duration *
this->nb_channels:
if (this->frame->format == AV_SAMPLE_FMT_S16P) {

const int16_t *p = (const int16_t *)this->frame->data[0];


for (int i = 0; i < nb_samples; i++, p++) {

if (*p < this->silence->noise && *p > -silence->noise) {

if (!this->silence->start) {

this->silence->nb_null_samples++;

if (this->silence->nb_null_samples >= nb_samples_notify) {
//nb_samples_notify

this->silence->start = this->frame->pts - (int64_t)(this->silence->duration
/ av_q2d(time_base) + .5);


Log::write("silence detected start = " + std::to_string(this->getCurrentSec
()));

}

}

} else {

if (this->silence->start) {

this->silent = false;

Log::write("silence detected end = " + std::to_string(this->getCurrentSec
()));

}

this->silence->nb_null_samples = this->silence->start = 0;

}

}

}

nb_samples = 2304
srate = 48000
nb_chaneks = 2
noise = 0.001
duratiion = 0.7
//
input video file format - * .ts
audio codec - mp2

In "*p" I get very strange data (for example -22634) and as a result,
silence was not detected.

Please tell me what I'm doing wrong? (because ffmpeg can find silence in
this file)
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