Play IMA ADPCM Audio with NAudio

Question

I have a file with no header with IMA ADPCM raw data stored, I would like to play it using NAudio. In Audacity, using this config plays without problems:

Encoding: VOX ADPCM 
Byte order: No Endianness
Channels: 1 Channel (Mono)
Start offset: 0 bytes
Amount to import: 100%
Sample rate: 22050Hz

This is the code I'm using, but I always get a System.DivideByZeroException error.

internal void PlayIMAAudio(WaveOut AudioPlayer, byte[] IMAData, int Frequency, int Bits, int Channels)
{
    if (AudioPlayer.PlaybackState == PlaybackState.Stopped)
    {
        MemoryStream AudioSample = new MemoryStream(IMAData);
        ImaAdpcmWaveFormat FileFormat = new ImaAdpcmWaveFormat(Frequency, Channels, Bits);
        RawSourceWaveStream provider = new RawSourceWaveStream(AudioSample, FileFormat);
        AudioPlayer.Init(provider);
        AudioPlayer.Play();
    }
}

How could I fix it?

Thanks!

Mark Heath Mark Heath · Accepted Answer · 2021-01-09T17:51:46

You can't usually play compressed formats directly. Pass the RawSourceWaveStream into WaveFormatConversionStream.CreatePcmStream to get to PCM. That should work if you have the right codec available on your PC and if you've correctly specified the source WaveFormat

Play IMA ADPCM Audio with NAudio

1 Answers