IEnumerable<AudioChunk> StreamDataCore( AiffChunkHeader chunk, PrimitiveReader reader )
{
int offset = reader.ReadInt32();
int blockSize = reader.ReadInt32();
long length = (uint)chunk.DataSize - 8; // Signed number to unsigned number.
int bufferLength = bufferSize; // Approximately one second each.
while( length > 0 ) {
int currentBufferSize = (int)Math.Min( bufferLength, length );
byte[] data = reader.ReadBytes( currentBufferSize );
info.Data = transformer.Transform( data, actualBitsPerSample );
length -= bufferLength;
yield return info;
}
}
void ProcessCommonChunk( AiffChunkHeader chunk, PrimitiveReader reader )
{
byte[] chunkData = reader.ReadBytes( chunk.DataSize );
Stream source = reader.stream;
reader.stream = new MemoryStream( chunkData );
int channelsCount = reader.ReadInt16();
uint frameCount = reader.ReadUInt32();
int bitsPerSample = reader.ReadInt16();
byte[] sampleRateBytes = reader.ReadBytes( 10 );
double sampleRate = ConvertFromIeeeExtended( sampleRateBytes );
Console.WriteLine( sampleRate );
AppendInfoLine( 2, "Channels Count: {0}", channelsCount );
AppendInfoLine( 2, "Sample rate (frames/sec): {0}", sampleRate );
AppendInfoLine( 2, "Bits per sample: {0}", bitsPerSample );
AppendInfoLine( 2, "Frame count: {0}", frameCount );
int byteRate = (int)Math.Ceiling( sampleRate ) * channelsCount * bitsPerSample / 8;
info.Frequency = (int)sampleRate;
Console.WriteLine( "BPS:" + bitsPerSample + ", SR:" + info.Frequency );
transformer = EmptyTransformer.Instance;
if( bitsPerSample > 8 && bitsPerSample <= 16 ) {
transformer = BigEndian16BitTo16BitTransformer.Instance;
}
if( bitsPerSample > 16 && bitsPerSample <= 24 ) {
transformer = BigEndian24BitTo16BitTransformer.Instance;
}
// Number of bytes that make up a second's worth of audio data.
bufferSize = byteRate;
info.Channels = channelsCount;
actualBitsPerSample = bitsPerSample;
// TODO: Remove this hackery.
if( bitsPerSample > 16 )
bitsPerSample = 16;
info.BitsPerSample = bitsPerSample;
if( aifcFormat ) {
string compressionType = reader.ReadASCIIString( 4 );
string compressionName = reader.ReadASCIIString( reader.ReadByte() );
AppendInfoLine( 2, "Compression type: {0}", compressionType );
AppendInfoLine( 2, "Compression name: {0}", compressionName );
switch( compressionType ) {
case "NONE":
case "sowt":
break;
case "alaw":
case "ALAW":
info.BitsPerSample = 16;
transformer = ALawTransformer.Instance;
break;
case "ulaw":
case "ULAW":
info.BitsPerSample = 16;
transformer = MuLawTransformer.Instance;
break;
}
}
reader.stream = source;
}
void ProcessFormatVersionChunk( AiffChunkHeader chunk, PrimitiveReader reader )
{
uint timeStamp = reader.ReadUInt32();
AppendInfoLine( 2, "Format timestamp: {0} (hex {1})", timeStamp, timeStamp.ToString( "X8" ) );
}
static AiffChunkHeader ReadChunkHeader( PrimitiveReader reader )
{
AiffChunkHeader chunk = new AiffChunkHeader();
chunk.Signature = reader.ReadASCIIString( 4 );
chunk.DataSize = reader.ReadInt32();
return chunk;
}
