将输入流式传输到System.Speech.Recognition.SpeechRecognitionEngine

Question

我试图从TCP套接字在C#中进行"流式"语音识别.我遇到的问题是SpeechRecognitionEngine.SetInputToAudioStream()似乎需要一个可以寻找的定义长度的Stream.现在,我能想到的唯一方法就是在更多输入进来时在MemoryStream上重复运行识别器.

这里有一些代码来说明:

            SpeechRecognitionEngine appRecognizer = new SpeechRecognitionEngine();

            System.Speech.AudioFormat.SpeechAudioFormatInfo formatInfo = new System.Speech.AudioFormat.SpeechAudioFormatInfo(8000, System.Speech.AudioFormat.AudioBitsPerSample.Sixteen, System.Speech.AudioFormat.AudioChannel.Mono);

            NetworkStream stream = new NetworkStream(socket,true);
            appRecognizer.SetInputToAudioStream(stream, formatInfo);
            // At the line above a "NotSupportedException" complaining that "This stream does not support seek operations."

有谁知道怎么解决这个问题？它必须支持某种类型的流输入,因为它使用SetInputToDefaultAudioDevice()与麦克风一起工作正常.

谢谢,肖恩

Answer 1

我通过覆盖流类来获得实时语音识别:

class SpeechStreamer : Stream
{
    private AutoResetEvent _writeEvent;
    private List<byte> _buffer;
    private int _buffersize;
    private int _readposition;
    private int _writeposition;
    private bool _reset;

    public SpeechStreamer(int bufferSize)
    {
        _writeEvent = new AutoResetEvent(false);
         _buffersize = bufferSize;
         _buffer = new List<byte>(_buffersize);
         for (int i = 0; i < _buffersize;i++ )
             _buffer.Add(new byte());
        _readposition = 0;
        _writeposition = 0;
    }

    public override bool CanRead
    {
        get { return true; }
    }

    public override bool CanSeek
    {
        get { return false; }
    }

    public override bool CanWrite
    {
        get { return true; }
    }

    public override long Length
    {
        get { return -1L; }
    }

    public override long Position
    {
        get { return 0L; }
        set {  }
    }

    public override long Seek(long offset, SeekOrigin origin)
    {
        return 0L;
    }

    public override void SetLength(long value)
    {

    }

    public override int Read(byte[] buffer, int offset, int count)
    {
        int i = 0;
        while (i<count && _writeEvent!=null)
        {
            if (!_reset && _readposition >= _writeposition)
            {
                _writeEvent.WaitOne(100, true);
                continue;
            }
            buffer[i] = _buffer[_readposition+offset];
            _readposition++;
            if (_readposition == _buffersize)
            {
                _readposition = 0;
                _reset = false;
            }
            i++;
        }

        return count;
    }

    public override void Write(byte[] buffer, int offset, int count)
    {
        for (int i = offset; i < offset+count; i++)
        {
            _buffer[_writeposition] = buffer[i];
            _writeposition++;
            if (_writeposition == _buffersize)
            {
                _writeposition = 0;
                _reset = true;
            }
        }
        _writeEvent.Set();

    }

    public override void Close()
    {
        _writeEvent.Close();
        _writeEvent = null;
        base.Close();
    }

    public override void Flush()
    {

    }
}

...并使用它的实例作为SetInputToAudioStream方法的流输入.一旦流返回长度或返回的计数小于请求的数量,识别引擎就认为输入已完成.这将设置一个永不完成的循环缓冲区.

Answer 2

您是否尝试过将网络流包装在 System.IO.BufferedStream 中？

NetworkStream netStream = new NetworkStream(socket,true);
BufferedStream buffStream = new BufferedStream(netStream, 8000*16*1); // buffers 1 second worth of data
appRecognizer.SetInputToAudioStream(buffStream, formatInfo);