private void SetupAudio(SoundFormat audioFormat, AcmEncoder audioEncoder)
{
IntPtr pwfx = audioFormat.ToPtr();
try {
Avi32Interop.AVISTREAMINFO asi = new Avi32Interop.AVISTREAMINFO();
asi.fccType = Avi32Interop.streamtypeAUDIO;
asi.dwScale = audioFormat.BlockAlign;
asi.dwRate = audioFormat.AverageBytesPerSecond;
asi.dwStart = 0;
asi.dwLength = -1;
asi.dwInitialFrames = 0;
asi.dwSuggestedBufferSize = 0;
asi.dwQuality = -1;
asi.dwSampleSize = audioFormat.BlockAlign;
int hr = Avi32Interop.AVIFileCreateStream(this.pAviFile, out this.pAudioStream, ref asi);
if (hr != 0)
{
throw new AviException("AVIStreamSetFormat", hr);
}
hr = Avi32Interop.AVIStreamSetFormat(this.pAudioStream, 0, pwfx, audioFormat.ToalSize);
if (hr != 0)
{
throw new AviException("AVIStreamSetFormat", hr);
}
if (audioEncoder != null)
{
audioEncoder.Open();
}
this.audioFormat = audioFormat;
this.audioEncoder = audioEncoder;
}
finally {
Marshal.FreeHGlobal(pwfx);
}
}
public static AcmConvertionMap GetConvertionMap(SoundFormat[] inputFormats, SoundFormatTag tagFilter)
{
// First, we enumerate convertion formats
AcmConvertionMap initConvertionMap = new AcmConvertionMap();
int maxFormatSize = GetMaxFormatSize();
// Enumerate acm drivers
foreach (int driverId in GetDriverIds())
{
// Open driver
IntPtr phDriver;
int mmr = AcmInterop.acmDriverOpen(out phDriver, driverId, 0);
if (mmr != 0)
{
continue;
}
// For each input format, we do enumeration
foreach (SoundFormat inputFormat in inputFormats)
{
// Fill format details struct
AcmInterop.ACMFORMATDETAILS fmtDetails = new AcmInterop.ACMFORMATDETAILS();
IntPtr pwfxFormat = inputFormat.ToPtr(maxFormatSize);
fmtDetails.cbStruct = Marshal.SizeOf(fmtDetails);
fmtDetails.pwfx = pwfxFormat;
fmtDetails.cbwfx = maxFormatSize;
// Enumerate convertion formats
callbackFormats = new List <SoundFormat>();
IntPtr pwfxInput = inputFormat.ToPtr();
mmr = AcmInterop.acmFormatEnum(phDriver, ref fmtDetails, FormatEnumCallback, IntPtr.Zero,
AcmInterop.ACM_FORMATENUMF_CONVERT);
Marshal.FreeHGlobal(pwfxInput);
// Add formats to the map (if succeed)
if (mmr == 0)
{
initConvertionMap.Add(inputFormat, callbackFormats);
}
callbackFormats = null;
}
// Close driver
mmr = AcmInterop.acmDriverClose(phDriver, 0);
}
// Now we query ACM to make sure each convertion is supported
AcmConvertionMap finalConvertionMap = new AcmConvertionMap();
SoundFormat[] inputs = initConvertionMap.GetInputs();
foreach (SoundFormat inputFormat in inputs)
{
IntPtr pwfxSrc = inputFormat.ToPtr();
foreach (SoundFormat outputFormat in initConvertionMap.GetOutputs(inputFormat))
{
// Filter tags
if (tagFilter != SoundFormatTag.UNKNOWN && outputFormat.Tag != tagFilter)
{
continue;
}
IntPtr phs;
IntPtr pwfxDst = outputFormat.ToPtr();
// Open acm stream using the query flag
int mmr = AcmInterop.acmStreamOpen(out phs, IntPtr.Zero, pwfxSrc, pwfxDst, IntPtr.Zero, IntPtr.Zero,
UIntPtr.Zero, AcmInterop.ACM_STREAMOPENF_QUERY);
Marshal.FreeHGlobal(pwfxDst);
// Add format to the final map if succeed
if (mmr == 0)
{
finalConvertionMap.Add(inputFormat, outputFormat);
}
}
Marshal.FreeHGlobal(pwfxSrc);
}
return(finalConvertionMap);
}