NAudio converting samples buffer to wave buffer

Question

My goal - to make processing and playback of audio data in real-time by NAudio. The application uses different formats: 8bit pcm, 16bit pcm, 24bit pcm. For playback, I use WaveOut and BufferedWaveProvider. The difficulty arises with the processing of individual samples in real time. To convert raw data into samples, I use the following code:

var vaweProviderIn = new BufferedWaveProvider(format);
vaweProviderIn.AddSamples(waveBuffer, 0, waveBuffer.Length);
var sampleProvider = vaweProviderIn.ToSampleProvider();
sampleProvider.Read(sampleBuffer, 0, sampleBufferSize);
//samples processing

The question is how to convert the samples buffer back to the wave buffer, to play it?

SolderingIronMen SolderingIronMen · Accepted Answer · 2018-01-26T18:21:23

I wrote my own code to solve this problem.

    private enum BPS {PCM_16Bit = 16, PCM_24Bit = 24};

    /// <summary>
    /// Converting the Sample Buffer to the Byte Buffer
    /// </summary>
    /// <param name="samples"></param>
    /// <param name="format"></param>
    /// <returns></returns>
    private byte[] samplesToVawe(float[] samples, WaveFormat format)
    {
        Int32 intSample;
        UInt32 sample4Byte;
        byte[] byteBuffer = new byte[samples.Length * (format.BitsPerSample / 8)];
        uint byteBufIndex = 0;

        for (uint i = 0; i < samples.Length; i++)
        {
            //convert 1 sample into 4 byte integer
            intSample = (Int32)(samples[i] * Int32.MaxValue);
            sample4Byte = (UInt32)intSample;

            switch((BPS)format.BitsPerSample)
            {
                case BPS.PCM_24Bit:
                    byteBuffer[byteBufIndex++] = (byte)(sample4Byte >> 8);
                    byteBuffer[byteBufIndex++] = (byte)(sample4Byte >> 16);
                    byteBuffer[byteBufIndex++] = (byte)(sample4Byte >> 24);
                    break;

                case BPS.PCM_16Bit:
                    byteBuffer[byteBufIndex++] = (byte)(sample4Byte >> 16);
                    byteBuffer[byteBufIndex++] = (byte)(sample4Byte >> 24);
                    break;
            }                
        }

        return byteBuffer;
    }

NAudio converting samples buffer to wave buffer

1 Answers