Question

我目前能够：从音频输入记录数据，在磁盘上使用该数据生成wav文件，从磁盘播放wav。
我要完成的工作：获取通过NAudio读取的原始字节，将wav，特定字节转换为mp3，播放mp3（不在磁盘上写入任何内容）。

使用的代码：

    public WaveIn waveSource = null;
    public WaveFileWriter waveFile = null;
    public List<byte> soundBytesList = new List<byte>();

    private void waveSource_DataAvailable(object sender, WaveInEventArgs e)
    {
        if (waveFile != null)
            for (int i = 0; i < e.BytesRecorded; ++i)
                soundBytesList.Add(e.Buffer[i]);
            waveFile.Write(e.Buffer, 0, e.BytesRecorded);
            waveFile.Flush();
    }

    public void waveSource_RecordingStopped(object sender, StoppedEventArgs e)
    {
        if (waveSource != null)
        {
            waveSource.Dispose();
            waveSource = null;
        }
        if (waveFile != null)
        {
            waveFile.Dispose();
            waveFile = null;
        }
    }

    private void RecordButton_MouseDown(object sender, EventArgs e)
    {
        waveSource = new WaveIn();
        waveSource.WaveFormat = new WaveFormat(44100, 1);

        waveSource.DataAvailable += new EventHandler<WaveInEventArgs>(waveSource_DataAvailable);
        waveSource.RecordingStopped += new EventHandler<StoppedEventArgs>(waveSource_RecordingStopped);

        waveFile = new WaveFileWriter("test.wav", waveSource.WaveFormat);

        waveSource.StartRecording();
    }

    private void RecordButton_MouseUp(object sender, EventArgs e)
    {
        waveSource.StopRecording();

        byte[] soundBytesArrayWAV = soundBytesList.ToArray();          
        byte[] outB = ConvertWavToMp3(soundBytesArrayWAV );
        File.WriteAllBytes("test.mp3", outB);
    }

        public byte[] ConvertWavToMp3(byte[] wavFile)
        {
            using (var retMs = new MemoryStream())
            using (var ms = new MemoryStream(wavFile))
            using (var rdr = new WaveFileReader(ms))
            using (var wtr = new LameMP3FileWriter(retMs, rdr.WaveFormat, 128))
            {
                rdr.CopyTo(wtr);
                wtr.Flush();
                return retMs.ToArray();
            }
        }

问题是我在ConvertWavToMp3方法上遇到错误，但说提供的字节数组（soundBytesArrayWAV）没有RIFF（特定于波形的标头）。我的猜测是，我没有正确地使用soundBytesList中的所有字节，因为如果我将所有字节加载到内存中（从写入wav的磁盘中），转换将正常进行。你能帮我个忙吗？

Answer 1

根据@Jon Skeet的建议更新的功能代码如下：

    public WaveIn waveSource = null;
    public WaveFileWriter waveFile = null;
    public MemoryStream memStream = null;

    private void waveSource_DataAvailable(object sender, WaveInEventArgs e)
    {
        if (waveFile != null)
        {
            waveFile.Write(e.Buffer, 0, e.BytesRecorded);
            waveFile.Flush();
        }
    }

    public void waveSource_RecordingStopped(object sender, StoppedEventArgs e)
    {
        if (waveSource != null)
        {
            waveSource.Dispose();
            waveSource = null;
        }
        if (waveFile != null)
        {
            waveFile.Dispose();
            waveFile = null;
        }
    }

    private void RecordButton_MouseDown(object sender, EventArgs e)
    {
        waveSource = new WaveIn();
        waveSource.WaveFormat = new WaveFormat(44100, 1);

        waveSource.DataAvailable += new EventHandler<WaveInEventArgs>(waveSource_DataAvailable);
        waveSource.RecordingStopped += new EventHandler<StoppedEventArgs>(waveSource_RecordingStopped);

        memStream = new MemoryStream();
        waveFile = new WaveFileWriter(memStream, waveSource.WaveFormat);

        waveSource.StartRecording();
    }

    private void RecordButton_MouseUp(object sender, EventArgs e)
    {
        waveSource.StopRecording();

        byte[] outB = memStream.ToArray();
        File.WriteAllBytes("test.mp3", outB);
    }

如何使用C＃NAudio操作字节？

1 个答案: