public static extern MmResult acmStreamOpen2(
out IntPtr hAcmStream,
IntPtr hAcmDriver,
IntPtr sourceFormatPointer,
IntPtr destFormatPointer,
[In] WaveFilter waveFilter,
IntPtr callback,
IntPtr instance,
AcmStreamOpenFlags openFlags);
public static extern MmResult acmStreamOpen(
out IntPtr hAcmStream,
IntPtr hAcmDriver,
[In, MarshalAs(UnmanagedType.CustomMarshaler, MarshalType = "NAudio.Wave.WaveFormatCustomMarshaler")]
WaveFormat sourceFormat,
[In, MarshalAs(UnmanagedType.CustomMarshaler, MarshalType = "NAudio.Wave.WaveFormatCustomMarshaler")]
WaveFormat destFormat,
[In] WaveFilter waveFilter,
IntPtr callback,
IntPtr instance,
AcmStreamOpenFlags openFlags);
/// <summary>
/// Creates a new ACM stream to convert one format to another, using a
/// specified driver identifier and wave filter
/// </summary>
/// <param name="driverId">the driver identifier</param>
/// <param name="sourceFormat">the source format</param>
/// <param name="waveFilter">the wave filter</param>
public AcmStream(IntPtr driverId, WaveFormat sourceFormat, WaveFilter waveFilter)
{
int sourceBufferSize = Math.Max(16384, sourceFormat.AverageBytesPerSecond);
this.sourceFormat = sourceFormat;
sourceBufferSize -= (sourceBufferSize % sourceFormat.BlockAlign);
MmException.Try(AcmInterop.acmDriverOpen(out driverHandle, driverId, 0), "acmDriverOpen");
IntPtr sourceFormatPointer = WaveFormat.MarshalToPtr(sourceFormat);
try
{
MmException.Try(AcmInterop.acmStreamOpen2(out streamHandle, driverHandle,
sourceFormatPointer, sourceFormatPointer, waveFilter, IntPtr.Zero, IntPtr.Zero, AcmStreamOpenFlags.NonRealTime), "acmStreamOpen");
}
finally
{
Marshal.FreeHGlobal(sourceFormatPointer);
}
streamHeader = new AcmStreamHeader(streamHandle, sourceBufferSize, SourceToDest(sourceBufferSize));
}