如何使用NAudio播放UDP数据包中的音频流？

Question

我正在从Voicemeeter本地接收数据，后者使用VBAN协议发送字节流。

我正在尝试使用NAudio解码字节并使用WaveOutEvent播放音频。我的实现与NAudioDemo中的NetworkChatDemo几乎相同，请查看此link以了解有关NAudio的更多信息，它是一个很棒的音频库，非常感谢Mark Heath。

我的实现：

private readonly ILogger<AudioController> _logger;
        private NetworkAudioPlayer player;
        private readonly INetworkChatCodec _codec;


        public AudioController(ILogger<AudioController> logger)
        {
            _logger = logger;
            _codec = new ALawChatCodec();
        }

        [HttpGet]
        [Route("start")]
        public IActionResult Start()
        {

            var receiver = new UdpAudioReceiver(6980);
            player = new NetworkAudioPlayer(_codec, receiver);

            return Ok("Hello");
        }

网络音频播放器：

private readonly INetworkChatCodec codec;
    private readonly IAudioReceiver receiver;
    private readonly IWavePlayer waveOut;
    private readonly BufferedWaveProvider waveProvider;

    public NetworkAudioPlayer(INetworkChatCodec codec, IAudioReceiver receiver)
    {
        this.codec = codec;
        this.receiver = receiver;
        receiver.OnReceived(OnDataReceived);

        waveOut = new WaveOutEvent();
        waveProvider = new BufferedWaveProvider(codec.RecordFormat);
        waveProvider.BufferDuration = TimeSpan.FromSeconds(300);
        waveOut.Init(waveProvider);
        waveOut.Play();
    }

    void OnDataReceived(byte[] compressed)
    {
        byte[] decoded = codec.Decode(compressed, 0, compressed.Length);
        waveProvider.AddSamples(decoded, 0, decoded.Length);
    }

    public void Dispose()
    {
        receiver?.Dispose();
        waveOut?.Dispose();
    }

我在此实现中遇到两个问题：

• 首先，我无法将BufferDuration设置为无限值，因为它是实时流。
• 第二，我什么都听不到，但听不到声音。

如何将BufferDuration设置为无穷大？如何正确播放音频？

更新：通过将bufferPorivider的DiscardOnBufferOverflow的值设置为true，我能够解决第一个问题。

关于噪声问题，我已经从question到达解决方案，Mark Heath提到了

而且，您确定接收到的网络数据包中没有周围的元数据吗？如果是这样，则需要将其剥离，否则会导致噪音。

所以，我将样本添加到BufferProvider时将offset的值更改为等于28，这会导致异常：

  void OnDataReceived(byte[] compressed)
        {
            var l = compressed.Length;
            waveProvider.AddSamples(compressed, 28, compressed.Length);
        }

堆栈跟踪：

    > 
> System.ArgumentException
  HResult=0x80070057
  Message=Source array was not long enough. Check the source index, length, and the array's lower bounds. (Parameter 'sourceArray')
  Source=System.Private.CoreLib
  StackTrace:
   at System.Array.Copy(Array sourceArray, Int32 sourceIndex, Array destinationArray, Int32 destinationIndex, Int32 length, Boolean reliable)
   at System.Array.Copy(Array sourceArray, Int32 sourceIndex, Array destinationArray, Int32 destinationIndex, Int32 length)
   at NAudio.Utils.CircularBuffer.Write(Byte[] data, Int32 offset, Int32 count)
   at NAudio.Wave.BufferedWaveProvider.AddSamples(Byte[] buffer, Int32 offset, Int32 count)
   at POC.AudioStreaming.AudioManagers.NetworkAudioPlayer.OnDataReceived(Byte[] compressed) in C:\dev\POC.AudioStreaming\POC.AudioStreaming\AudioManagers\NetworkAudioPlayer.cs:line 41
   at POC.AudioStreaming.AudioManagers.UdpAudioReceiver.ListenerThread(Object state) in C:\dev\POC.AudioStreaming\POC.AudioStreaming\AudioManagers\UdpAudioReceiver.cs:line 38
   at System.Threading.QueueUserWorkItemCallback.<>c.<.cctor>b__6_0(QueueUserWorkItemCallback quwi)
   at System.Threading.ExecutionContext.RunForThreadPoolUnsafe[TState](ExecutionContext executionContext, Action`1 callback, TState& state)
   at System.Threading.QueueUserWorkItemCallback.Execute()
   at System.Threading.ThreadPoolWorkQueue.Dispatch()
   at System.Threading._ThreadPoolWaitCallback.PerformWaitCallback()

我该如何解决此异常？

Answer 1

我已经使用跳过功能解决了从接收到的数据包中删除前28个字节的异常：

 void OnDataReceived(byte[] compressed)
    {
        byte[] buffer = compressed.Skip(28).ToArray();
        waveProvider.AddSamples(buffer, 0, buffer.Length);
    }

通过解决异常，我能够很好地听到音频。另外，我已经回答了我的问题。