I am working on a click generator using nAudio. As a test, I created a ISampleProvidor class to read/play from an audio file. The iSampleProvider reads in a PCM (32-bit ieee) wav file and then plays it back using the WaveOut player. The WaveOut plays only about 1/4 of the audio passed via the IsampleProvidor Read() method. This results in a choppy playback. The ISampleProvider read() method requests the correct amount of data at the correct time intervals, but the WaveOut only plays the first 25% of the samples provided back to the interface. Any Idea how to address this, or am I using the wrong classes to build a click track (the BufferedWaveProvider might also work, but it only buffers 5 seconds of audio)?
public void TestSampleProvider()
{
ISampleProvider mySamples = new MySamples();
var _waveOut = new WaveOut(WaveCallbackInfo.FunctionCallback()) {DeviceNumber = 0};
_waveOut.Init(mySamples);
_waveOut.Play();
Console.ReadLine();
}
public class MySamples : ISampleProvider
{
private float[] samplesFloats;
private int position;
private WaveFileReader clicksound;
public int Read(float[] buffer, int offset, int count)
{
var copyCount = count;
if (position + copyCount > samplesFloats.Count())
{
copyCount = samplesFloats.Count() - position;
}
Console.WriteLine("samplesFloats {0} position {1} copyCount {2} offset {3} time {4}", samplesFloats.Count(), position, copyCount, offset, DateTime.Now.Millisecond);
Buffer.BlockCopy(samplesFloats, position, buffer, offset, copyCount);
position += copyCount;
return copyCount;
}
public MySamples()
{
clicksound = new WaveFileReader(@"C:\temp\sample.wav");
WaveFormat = clicksound.WaveFormat;
samplesFloats = new float[clicksound.SampleCount];
for (int i = 0; i < clicksound.SampleCount; i++)
{
samplesFloats[i] = clicksound.ReadNextSampleFrame()[0];//it;s a mono file
}
}
public WaveFormat WaveFormat { get; private set; }
}
I think there may be an issue with the WaveOut using the ISampleProvider, so I used the IWaveProvider interface to do the same thing. In fact, here's a bare bones class for sending a non-ending click to the waveout. This might run into memory issues if you let it run a long time but for pop songs it should be fine. Also this will only work for 32-bit files (note the *4 on the byte buffer)
public class MyClick : IWaveProvider
{
private int position;
private WaveFileReader clicksound;
private byte[] samplebuff;
MemoryStream _byteStream = new System.IO.MemoryStream();
public MyClick(float bpm=120)
{
clicksound = new WaveFileReader(@"click_sample.wav");
var bpmsampleslen = (60 / bpm) * clicksound.WaveFormat.SampleRate;
samplebuff = new byte[(int) bpmsampleslen*4];
clicksound.Read(samplebuff, 0,(int) clicksound.Length);
_byteStream.Write(samplebuff, 0, samplebuff.Length);
_byteStream.Position = 0;
WaveFormat = clicksound.WaveFormat;
}
public int Read(byte[] buffer, int offset, int count)
{
//we reached the end of the stream add another one to the end and keep playing
if (count + _byteStream.Position > _byteStream.Length)
{
var holdpos = _byteStream.Position;
_byteStream.Write(samplebuff, 0, samplebuff.Length);
_byteStream.Position = holdpos;
}
return _byteStream.Read(buffer, offset, count);
}
public WaveFormat WaveFormat { get; private set; }
}