public void Dispose()
{
if (disposed)
{
return;
}
GC.SuppressFinalize(this);
if (handle != IntPtr.Zero)
{
MP3Library.Delete(handle);
MP3Library.Exit();
}
disposed = true;
}
public MP3Decoder()
{
Errors error = (Errors)MP3Library.Init();
if (error != Errors.MPG123_OK)
{
throw new InvalidOperationException("Couldn't create the MP3 decoder, Error " + error);
}
IntPtr err;
handle = MP3Library.New(null, out err);
if (error != Errors.MPG123_OK)
{
throw new InvalidOperationException("Couldn't create the MP3 decoder, Error " + error);
}
}
/// <summary>
/// Decodes mp3 to PCM samples.
/// </summary>
/// <param name="input">MP3 in a MemoryStream</param>
/// <param name="output">PCM samples in a MemoryStream</param>
/// <returns>The amount of samples decoded</returns>
public unsafe int Decode(MemoryStream input, MemoryStream output)
{
if (disposed)
{
throw new ObjectDisposedException("MP3Decoder");
}
IntPtr inPtr;
IntPtr outPtr;
byte[] buf = output.GetBuffer();
byte[] inbuf = output.GetBuffer();
UIntPtr done = new UIntPtr(0);
fixed(byte *bufptr = buf, inbufptr = inbuf)
{
inPtr = new IntPtr(inbufptr);
outPtr = new IntPtr(bufptr);
int err = MP3Library.Decode(handle, inPtr, new UIntPtr(Convert.ToUInt32(input.Length - input.Position)), outPtr, new UIntPtr(Convert.ToUInt32(output.Length - output.Position) * 2), ref done);
while ((Errors)err == Errors.MPG123_NEW_FORMAT) // Try out new format
{
err = MP3Library.Decode(handle, inPtr, new UIntPtr(0), outPtr, new UIntPtr(Convert.ToUInt32(output.Length - output.Position) * 2), ref done);
}
if ((Errors)err < Errors.MPG123_OK && (Errors)err != Errors.MPG123_NEED_MORE) // oopsie doopsie didn't worky
{
throw new InvalidOperationException("Failed to decode, error " + (Errors)err);
}
}
output.Position = done.ToUInt32() / 2;
output.SetLength(output.Position);
output.Position = 0;
return((int)done.ToUInt32());
}
