private static WaveStream NormalizeStream(WaveStream stream)
{
WaveStream audioStream = stream;
if (audioStream.WaveFormat.BitsPerSample != 16)
{
audioStream = new Wave32To16CaptureStream(stream);
}
if (audioStream.WaveFormat.Channels != 1)
{
audioStream = new MonoCaptureStream(audioStream);
}
if (audioStream.WaveFormat.BitsPerSample != 16000)
{
audioStream = new DownsampleCaptureStream(audioStream);
}
return(audioStream);
}
public LocalSpeechRecognizer(WaveStream stream)
{
this.recognizer = new SpeechRecognitionEngine();
this.recognizer.LoadGrammar(new DictationGrammar());
this.resultId = Guid.NewGuid().ToString();
this.lockObj = new object();
this.recognizer.SpeechRecognized += (sndr, evt) =>
{
string id = null;
lock (this.lockObj)
{
id = this.resultId;
this.resultId = Guid.NewGuid().ToString();
}
this.SpeechRecognized?.Invoke(this, new RecognitionEventArgs(evt, id));
};
this.recognizer.SpeechHypothesized += (snder, evt) =>
{
string id = null;
lock (this.lockObj)
{
id = this.resultId;
}
this.SpeechPredicted?.Invoke(this, new RecognitionEventArgs(evt, id, DateTime.Now - this.startTime));
};
WaveStream audioStream = stream;
if (audioStream.WaveFormat.BitsPerSample != 16)
{
audioStream = new Wave32To16CaptureStream(stream);
}
this.recognizer.SetInputToAudioStream(audioStream, new SpeechAudioFormatInfo(audioStream.WaveFormat.SampleRate, (AudioBitsPerSample)audioStream.WaveFormat.BitsPerSample, (AudioChannel)audioStream.WaveFormat.Channels));
}
