/// <summary>
/// Initializes the specified stream.
/// </summary>
/// <param name="stream">The stream.</param>
private unsafe void Initialize(Stream stream)
{
var parser = new RiffParser(stream);
FileFormatName = "Unknown";
// Parse Header
if (!parser.MoveNext() || parser.Current == null)
{
ThrowInvalidFileFormat();
return;
}
// Check that WAVE header is present
FileFormatName = parser.Current.Type;
if (FileFormatName != "WAVE")
{
throw new InvalidOperationException("Unsupported " + FileFormatName + " file format. Only WAVE.");
}
// Parse inside the first chunk
parser.Descend();
// Get all the chunk
var chunks = parser.GetAllChunks();
// Get "fmt" chunk
var fmtChunk = Chunk(chunks, "fmt ");
if (fmtChunk.Size < sizeof(WaveFormat.__PcmNative))
{
ThrowInvalidFileFormat();
}
try
{
Format = WaveFormat.MarshalFrom(fmtChunk.GetData());
}
catch (InvalidOperationException ex)
{
ThrowInvalidFileFormat(ex);
}
switch (Format.Encoding)
{
case WaveFormatEncoding.Pcm:
case WaveFormatEncoding.IeeeFloat:
case WaveFormatEncoding.Extensible:
case WaveFormatEncoding.Adpcm:
break;
default:
ThrowInvalidFileFormat();
break;
}
// Check for "data" chunk
var dataChunk = Chunk(chunks, "data");
startPositionOfData = dataChunk.DataPosition;
length = dataChunk.Size;
input.Position = startPositionOfData;
}
