private static AiffChunk ReadChunkHeader(BinaryReader br)
{
var chunk = new AiffChunk((uint)br.BaseStream.Position, ReadChunkName(br), ConvertInt(br.ReadBytes(4)));
return chunk;
}
private static AiffChunk ReadChunkHeader(BinaryReader br)
{
var chunk = new AiffChunk((uint)br.BaseStream.Position, ReadChunkName(br), ConvertInt(br.ReadBytes(4)));
return(chunk);
}
/// <summary>
/// Ensures valid AIFF header and then finds data offset.
/// </summary>
/// <param name="stream">The stream, positioned at the start of audio data</param>
/// <param name="format">The format found</param>
/// <param name="dataChunkPosition">The position of the data chunk</param>
/// <param name="dataChunkLength">The length of the data chunk</param>
/// <param name="chunks">Additional chunks found</param>
public static void ReadAiffHeader(System.IO.Stream stream, out WaveFormatProvider format, out long dataChunkPosition, out int dataChunkLength, List <AiffChunk> chunks)
{
dataChunkPosition = -1;
format = null;
BinaryReader br = new BinaryReader(stream);
if (ReadChunkName(br) != "FORM")
{
throw new FormatException("Not an AIFF file - no FORM header.");
}
uint fileSize = ConvertInt(br.ReadBytes(4));
string formType = ReadChunkName(br);
if (formType != "AIFC" && formType != "AIFF")
{
throw new FormatException("Not an AIFF file - no AIFF/AIFC header.");
}
dataChunkLength = 0;
while (br.BaseStream.Position < br.BaseStream.Length)
{
AiffChunk nextChunk = ReadChunkHeader(br);
if (nextChunk.ChunkName == "COMM")
{
short numChannels = ConvertShort(br.ReadBytes(2));
uint numSampleFrames = ConvertInt(br.ReadBytes(4));
short sampleSize = ConvertShort(br.ReadBytes(2));
double sampleRate = IEEE.ConvertFromIeeeExtended(br.ReadBytes(10));
format = new WaveFormatProvider((int)sampleRate, (int)sampleSize, (int)numChannels);
if (nextChunk.ChunkLength > 18 && formType == "AIFC")
{
// In an AIFC file, the compression format is tacked on to the COMM chunk
string compress = new string(br.ReadChars(4)).ToLower();
if (compress != "none")
{
throw new FormatException("Compressed AIFC is not supported.");
}
br.ReadBytes((int)nextChunk.ChunkLength - 22);
}
else
{
br.ReadBytes((int)nextChunk.ChunkLength - 18);
}
}
else if (nextChunk.ChunkName == "SSND")
{
uint offset = ConvertInt(br.ReadBytes(4));
uint blockSize = ConvertInt(br.ReadBytes(4));
dataChunkPosition = nextChunk.ChunkStart + 16 + offset;
dataChunkLength = (int)nextChunk.ChunkLength - 8;
br.ReadBytes((int)nextChunk.ChunkLength - 8);
}
else
{
if (chunks != null)
{
chunks.Add(nextChunk);
}
br.ReadBytes((int)nextChunk.ChunkLength);
}
if (nextChunk.ChunkName == "\0\0\0\0")
{
break;
}
}
if (format == null)
{
throw new FormatException("Invalid AIFF file - No COMM chunk found.");
}
if (dataChunkPosition == -1)
{
throw new FormatException("Invalid AIFF file - No SSND chunk found.");
}
}
/// <summary>
/// Ensures valid AIFF header and then finds data offset.
/// </summary>
/// <param name="stream">The stream, positioned at the start of audio data</param>
/// <param name="format">The format found</param>
/// <param name="dataChunkPosition">The position of the data chunk</param>
/// <param name="dataChunkLength">The length of the data chunk</param>
/// <param name="chunks">Additional chunks found</param>
public static void ReadAiffHeader(Stream stream, out NAudio.Wave.WaveFormat format, out long dataChunkPosition, out int dataChunkLength, List <AiffChunk> chunks)
{
dataChunkPosition = -1;
format = null;
BinaryReader br = new BinaryReader(stream);
if (ReadChunkName(br) != "FORM")
{
throw new FormatException("Not an AIFF file - no FORM header.");
}
uint fileSize = ConvertLong(br.ReadBytes(4));
if (ReadChunkName(br) != "AIFF")
{
throw new FormatException("Not an AIFF file - no AIFF header.");
}
dataChunkLength = 0;
while (br.BaseStream.Position < br.BaseStream.Length)
{
AiffChunk nextChunk = ReadChunkHeader(br);
if (nextChunk.chunkName == "COMM")
{
short numChannels = ConvertShort(br.ReadBytes(2));
uint numSampleFrames = ConvertLong(br.ReadBytes(4));
short sampleSize = ConvertShort(br.ReadBytes(2));
double sampleRate = ConvertExtended(br.ReadBytes(10));
format = new NAudio.Wave.WaveFormat((int)sampleRate, (int)sampleSize, (int)numChannels);
br.ReadBytes((int)nextChunk.chunkLength - 18);
}
else if (nextChunk.chunkName == "SSND")
{
uint offset = ConvertLong(br.ReadBytes(4));
uint blockSize = ConvertLong(br.ReadBytes(4));
dataChunkPosition = nextChunk.chunkStart + 16 + offset;
dataChunkLength = (int)nextChunk.chunkLength - 8;
br.ReadBytes((int)nextChunk.chunkLength - 8);
}
else
{
if (chunks != null)
{
chunks.Add(nextChunk);
}
br.ReadBytes((int)nextChunk.chunkLength);
}
if (nextChunk.chunkName == "\0\0\0\0")
{
break;
}
//Console.WriteLine("Read chunk {0} with length {1}", nextChunk.chunkName, nextChunk.chunkLength);
}
if (format == null)
{
throw new FormatException("Invalid AIFF file - No COMM chunk found.");
}
if (dataChunkPosition == -1)
{
throw new FormatException("Invalid AIFF file - No SSND chunk found.");
}
}