static IntPtr GetMagicCookie([NotNull] AudioFile audioFile, [NotNull] AudioConverter converter)
{
audioFile.GetPropertyInfo(AudioFilePropertyId.MagicCookieData, out var dataSize, out _);
var cookie = audioFile.GetProperty(AudioFilePropertyId.MagicCookieData, dataSize);
converter.SetProperty(AudioConverterPropertyId.DecompressionMagicCookie, dataSize, cookie);
return(cookie);
}
public void Initialize(Stream stream)
{
_audioFile = new AudioFile(AudioFileType.M4A, stream);
var inputDescription = _audioFile.GetProperty <AudioStreamBasicDescription>(AudioFilePropertyId.DataFormat);
if (inputDescription.AudioFormat != AudioFormat.AppleLossless)
{
throw new AudioUnsupportedException("The stream is not in Apple Lossless format.");
}
_outputDescription = GetOutputDescription(inputDescription);
_converter = new AudioConverter(ref inputDescription, ref _outputDescription, _audioFile);
_magicCookie = GetMagicCookie(_audioFile, _converter);
}