Using NAudio to play a WAV with custom codec

Question

I have a WAV file that has been recorded using a custom codec. The codec has been installed on my machine, and the WAV file plays fine on my machine using Windows Media player. I am using the NAudio routines to try and play the WAV file via some C# code. The values for the custom format look weird, but I have painstakingly checked them by analysing the WAV file header. Here is the best C# code I have come up with for playing the file:

WaveFormat wfOKI = WaveFormat.CreateCustomFormat(WaveFormatEncoding.DialogicOkiAdpcm, 8000, 1, 3000, 48, 3);
WaveStream wsRaw = new WaveFileReader(txtFileName.Text);
wsRaw = WaveFormatConversionStream.CreatePcmStream(wsRaw);    // Line A
wsRaw = new BlockAlignReductionStream(wsRaw);                 // Line B
WaveStream wsOKI = new RawSourceWaveStream(wsRaw, wfOKI);

WaveOut woCall = new WaveOut();
woCall.Init(wsOKI);    // <-- This line gives an error.
woCall.Play();

while (woCall.PlaybackState == PlaybackState.Playing)
{
    System.Threading.Thread.Sleep(300);
}

The Init() causes the following error: An unhandled exception of type 'NAudio.MmException' occurred in NAudio.dll. Additional information: WaveBadFormat calling waveOutOpen.

Is the code the correct strategy for playing a WAV with a custom codec? I have tried all four combinations of commenting out/in Lines A and B (with no difference to the error message).

I'm using Windows 7 64-bit, Visual Studio 2010 professional (project is set to x86), and version 1.6 of NAudio. I'm very new to NAudio, but did get a few lines going that played a "standard" WAV (i.e. a file that did not use a custom codec).

Mark Heath Mark Heath · Accepted Answer · 2012-10-31T12:31:17

If you have got a WAV file then there is no need for the RawSourceWaveStream. You can play the converted stream directly.

var wsRaw = new WaveFileReader(txtFileName.Text);
wsRaw = WaveFormatConversionStream.CreatePcmStream(wsRaw);
WaveOut woCall = new WaveOut();
woCall.Init(wsRaw);
woCall.Play();

Also, you should not be calling thread.sleep to wait for it to finish if you are using WaveOut. Try WaveOutEvent instead if you are not using this from an application with a GUI.

Using NAudio to play a WAV with custom codec

1 Answers