Hearing the Incoming audio from mic

问题:

i just want to hear what i say to microphone using NAudio and this is my code so far but the problem is i can't hear anything. any help would be appreciated.

public partial class frmMain : Form
    {
        private WaveIn waveIn; // Gets an audio from microphone
        private WaveOut waveOut; // Sends audio to speaker
        private BufferedWaveProvider waveProvider; // Gets an audio from stream

        public frmMain()
        {
            InitializeComponent();
        }

        private void frmMain_Load(object sender, EventArgs e)
        {
            waveOut = new WaveOut();
            waveIn = new WaveIn();
            waveProvider = new BufferedWaveProvider(waveIn.WaveFormat);

            waveOut.Init(waveProvider);             

            waveIn.DataAvailable += waveIn_DataAvailable;

            waveOut.Play();            
        }

        private void waveIn_DataAvailable(object sender, WaveInEventArgs e)
        {
            waveProvider.Read(e.Buffer, 0, e.BytesRecorded);
        }

        private void btnStop_Click(object sender, EventArgs e)
        {
            waveIn.StopRecording();
            waveIn.Dispose();
        }

        private void btnStart_Click(object sender, EventArgs e)
        {
            waveIn.StartRecording();
        }
    }

i will use this scenario in network programming on which i send the data from microphone to the socket then on the client side the BufferedWaveProvider will read the data then send it to the speaker. Please put also some comment if what is the better way to do it.

TIA

回答1:

Sample code as promised. Code is for a form with two buttons (named StartBtn and StopBtn).

public partial class Form1 : Form
{
    private WaveIn waveIn = null;
    private BufferedWaveProvider waveProvider = null;
    private WaveOut waveOut = null;

    public Form1()
    {
        InitializeComponent();
    }

    private void StartBtn_Click(object sender, EventArgs e)
    {
        if (waveIn != null)
            return;

        // create wave input from mic
        waveIn = new WaveIn(this.Handle);
        waveIn.BufferMilliseconds = 25;
        waveIn.RecordingStopped += waveIn_RecordingStopped;
        waveIn.DataAvailable += waveIn_DataAvailable;

        // create wave provider
        waveProvider = new BufferedWaveProvider(waveIn.WaveFormat);

        // create wave output to speakers
        waveOut = new WaveOut();
        waveOut.DesiredLatency = 100;
        waveOut.Init(waveProvider);
        waveOut.PlaybackStopped += wavePlayer_PlaybackStopped;

        // start recording and playback
        waveIn.StartRecording();
        waveOut.Play();
    }

    void waveIn_DataAvailable(object sender, WaveInEventArgs e)
    {
        // add received data to waveProvider buffer
        if (waveProvider != null)
            waveProvider.AddSamples(e.Buffer, 0, e.BytesRecorded);
    }

    private void StopBtn_Click(object sender, EventArgs e)
    {
        if (waveIn != null)
            waveIn.StopRecording();
    }

    void waveIn_RecordingStopped(object sender, StoppedEventArgs e)
    {
        // stop playback
        if (waveOut != null)
            waveOut.Stop();

        // dispose of wave input
        if (waveIn != null)
        {
            waveIn.Dispose();
            waveIn = null;
        }

        // drop wave provider
        waveProvider = null;
    }

    void wavePlayer_PlaybackStopped(object sender, StoppedEventArgs e)
    {
        // stop recording
        if (waveIn != null)
            waveIn.StopRecording();

        // dispose of wave output
        if (waveOut != null)
        {
            waveOut.Dispose();
            waveOut = null;
        }
    }
}

Note especially the waveIn.BufferMilliseconds and waveOut.DesiredLatency settings to reduce the lag times.

For compressing the data for network transmission I suggest using a different library to process the data blocks. You might need to tune the BufferMilliseconds value to reduce the overheads and get better compression ratios.

The Opus Codec looks like a reasonable option, with Opus.NET for C#.