Question

我正在使用多输入声卡，我希望实现多个输入的实时混音。所有输入都是立体声，所以我需要先将它们分开，混合选择的通道并将它们作为单声道流提供。

目标将是这样的混合频道1 [左] +频道3 [右] +频道4 [右] - ＆gt;单流。

我已经实现了这样的流程链：

1） WaveIn - ＆gt;为每个频道创建 BufferedWaveProvider - ＆gt;使用 wavein.DataAvailable + = {buffwavprovider [channel] .AddSamples（...）将样本（只是当前频道的样本）添加到每个BufferedWaveProvider ... 这给了我一个很好的BufferdWaveProvider列表。这里的分割音频部分正确实现。

2）选择多个BufferedWaveProviders并将它们提供给 MixingWaveProvider32 。然后创建一个WaveStream（使用WaveMixerStream32 and IWaveProvider）。

3）MultiChannelToMonoStream接受WaveStream并生成混合。这也有效。

但结果是，音频被切断了。就像缓冲区有些麻烦......

这是解决此问题的正确方法，还是有更好的解决方法？

编辑 - 已添加代码：

public class AudioSplitter
   {
      public List<NamedBufferedWaveProvider> WaveProviders { private set; get; }
      public string Name { private set; get; }
      private WaveIn _wavIn;
      private int bytes_per_sample = 4;

      /// <summary>
      /// Splits up one WaveIn into one BufferedWaveProvider for each channel
      /// </summary>
      /// <param name="wavein"></param>
      /// <returns></returns>
      public AudioSplitter(WaveIn wavein, string name)
      {
         if (wavein.WaveFormat.Encoding != WaveFormatEncoding.IeeeFloat)
            throw new Exception("Format must be IEEE float");


         WaveProviders = new List<NamedBufferedWaveProvider>(wavein.WaveFormat.Channels);

         Name = name;
         _wavIn = wavein;
         _wavIn.StartRecording();
         var outFormat = NAudio.Wave.WaveFormat.CreateIeeeFloatWaveFormat(wavein.WaveFormat.SampleRate, 1);

         for (int i = 0; i < wavein.WaveFormat.Channels; i++)
         {
            WaveProviders.Add(new NamedBufferedWaveProvider(outFormat) { DiscardOnBufferOverflow = true, Name = Name + "_" + i });
         }

         bytes_per_sample = _wavIn.WaveFormat.BitsPerSample / 8;
         wavein.DataAvailable += Wavein_DataAvailable;
      }


      /// <summary>
      /// add samples for each channel to bufferedwaveprovider
      /// </summary>
      /// <param name="sender"></param>
      /// <param name="e"></param>
      private void Wavein_DataAvailable(object sender, WaveInEventArgs e)
      {
         int channel = 0;
         byte[] buffer = e.Buffer;
         for (int i = 0; i < e.BytesRecorded - bytes_per_sample; i = i + bytes_per_sample)
         {
            byte[] channel_buffer = new byte[bytes_per_sample];

            for (int j = 0; j < bytes_per_sample; j++)
            {
               channel_buffer[j] = buffer[i + j];
            }

            WaveProviders[channel].AddSamples(channel_buffer, 0, channel_buffer.Length);

            channel++;

            if (channel >= _wavIn.WaveFormat.Channels)
               channel = 0;

         }

      }
   }

每个通道使用Audiosplitter可提供缓冲波提供商列表（单声道32位浮点数）。

 var mix = new MixingWaveProvider32(_waveProviders);
 var wps = new WaveProviderToWaveStream(mix);
 MultiChannelToMonoStream mms = new MultiChannelToMonoStream(wps);

 new Thread(() =>
  {
     byte[] buffer = new byte[4096];

     while (mms.Read(buffer, 0, buffer.Length) > 0 && isrunning)
     {


        using (FileStream fs = new FileStream("C:\\temp\\audio\\mono_32.wav", FileMode.Append, FileAccess.Write))
        {
           fs.Write(buffer, 0, buffer.Length);
        }

     }
  }).Start();

Answer 1

还有一些空间可供优化，但基本上这可以完成工作：

myletter = mycell.Value2 ' get the Value2 (without the cell format)

With mycell.Offset(1, 1)
    .NumberFormat = "@" ' first: format the destination cell as text
    .Value2 = myletter ' second: get the Value2 (just in case)
End With

我们需要为每个频道提供WaveProvider（WaveProviders [j]）。

NAudio - 实时波分裂和组合波

1 个答案: