using NAudio.Wave;
using NAudio.Wave.SampleProviders;
using SileroVad;
public static class FileReader
{
private static int SAMPLE_RATE = 16000;
private static Vad vad = new Vad();
public static void VadFile(string filePath)
{
var ext = Path.GetExtension(filePath).ToLower();
WaveStream waveFileReader;
switch (ext)
{
case ".wav":
waveFileReader = new WaveFileReader(filePath);
break;
case ".mp3":
waveFileReader = new Mp3FileReader(filePath);
break;
default:
throw new NotSupportedException($"not supported {ext}");
}
var TotalTime = waveFileReader.TotalTime;
ISampleProvider sampleProvider;
if (waveFileReader.WaveFormat.SampleRate != SAMPLE_RATE)
{
sampleProvider = new WdlResamplingSampleProvider(waveFileReader.ToSampleProvider(), SAMPLE_RATE).ToMono();
}
else
{
sampleProvider = waveFileReader.ToSampleProvider();
}
var array = new float[CountSamples(TotalTime)];
sampleProvider.Read(array, 0, array.Length);
List<VadSpeech> resul = vad.GetSpeechTimestamps(array, min_silence_duration_ms: 500, threshold: 0.5f);
var audioSpeech = VadHelper.GetSpeechSamples(array, resul);
var fileTrim = Path.ChangeExtension(filePath, "speech") + ".wav";
using var fileWriter = new WaveFileWriter(fileTrim, new WaveFormat(16000, 1));
foreach (var sample in audioSpeech)
{
fileWriter.WriteSample(sample);
}
fileWriter.Flush();
waveFileReader.Dispose();
}
private static int CountSamples(TimeSpan time)
{
WaveFormat waveFormat = new WaveFormat(16000, 1);
return TimeSpanToSamples(time, waveFormat);
}
private static int TimeSpanToSamples(TimeSpan time, WaveFormat waveFormat)
{
return (int)(time.TotalSeconds * (double)waveFormat.SampleRate) * waveFormat.Channels;
}
}[1] Silero Team. (2021). Silero VAD: pre-trained enterprise-grade Voice Activity Detector (VAD), Number Detector and Language Classifier. GitHub, GitHub repository, https://github.com/snakers4/silero-vad, hello@silero.ai.