/// <summary>
/// Reads the header part of a WAV file from a stream
/// </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 ReadWaveHeader(Stream stream, out WaveFormat format, out long dataChunkPosition, out int dataChunkLength, List <RiffChunk> chunks)
{
dataChunkPosition = -1;
format = null;
BinaryReader br = new BinaryReader(stream);
if (br.ReadInt32() != WaveInterop.mmioStringToFOURCC("RIFF", 0))
{
throw new FormatException("Not a WAVE file - no RIFF header");
}
uint fileSize = br.ReadUInt32(); // read the file size (minus 8 bytes)
if (br.ReadInt32() != WaveInterop.mmioStringToFOURCC("WAVE", 0))
{
throw new FormatException("Not a WAVE file - no WAVE header");
}
int dataChunkID = WaveInterop.mmioStringToFOURCC("data", 0);
int formatChunkId = WaveInterop.mmioStringToFOURCC("fmt ", 0);
dataChunkLength = 0;
// sometimes a file has more data than is specified after the RIFF header
long stopPosition = Math.Min(fileSize + 8, stream.Length);
// this -8 is so we can be sure that there are at least 8 bytes for a chunk id and length
while (stream.Position <= stopPosition - 8)
{
Int32 chunkIdentifier = br.ReadInt32();
Int32 chunkLength = br.ReadInt32();
if (chunkIdentifier == dataChunkID)
{
dataChunkPosition = stream.Position;
dataChunkLength = chunkLength;
stream.Position += chunkLength;
}
else if (chunkIdentifier == formatChunkId)
{
format = WaveFormat.FromFormatChunk(br, chunkLength);
}
else
{
if (chunks != null)
{
chunks.Add(new RiffChunk(chunkIdentifier, chunkLength, stream.Position));
}
stream.Position += chunkLength;
}
}
if (format == null)
{
throw new FormatException("Invalid WAV file - No fmt chunk found");
}
if (dataChunkPosition == -1)
{
throw new FormatException("Invalid WAV file - No data chunk found");
}
}
/// <summary>
/// Creates a cue list from the cue RIFF chunk and the list RIFF chunk
/// </summary>
/// <param name="cueChunkData">The data contained in the cue chunk</param>
/// <param name="listChunkData">The data contained in the list chunk</param>
internal CueList(byte[] cueChunkData, byte[] listChunkData)
{
int cueCount = BitConverter.ToInt32(cueChunkData, 0);
Dictionary <int, int> cueIndex = new Dictionary <int, int>();
int[] positions = new int[cueCount];
int cue = 0;
for (int p = 4; cueChunkData.Length - p >= 24; p += 24, cue++)
{
cueIndex[BitConverter.ToInt32(cueChunkData, p)] = cue;
positions[cue] = BitConverter.ToInt32(cueChunkData, p + 20);
}
string[] labels = new string[cueCount];
int labelLength = 0;
int cueID = 0;
Int32 labelChunkID = WaveInterop.mmioStringToFOURCC("labl", 0);
for (int p = 4; listChunkData.Length - p >= 16; p += labelLength + labelLength % 2 + 12)
{
if (BitConverter.ToInt32(listChunkData, p) == labelChunkID)
{
labelLength = BitConverter.ToInt32(listChunkData, p + 4) - 4;
cueID = BitConverter.ToInt32(listChunkData, p + 8);
cue = cueIndex[cueID];
labels[cue] = Encoding.Default.GetString(listChunkData, p + 12, labelLength - 1);
}
}
for (int i = 0; i < cueCount; i++)
{
cues.Add(new Cue(positions[i], labels[i]));
}
}
/// <summary>
/// Reads the header part of a WAV file from a stream
/// </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 ReadWaveHeader(Stream stream, out WaveFormat format, out long dataChunkPosition, out int dataChunkLength, List <RiffChunk> chunks)
{
dataChunkPosition = -1;
format = null;
BinaryReader br = new BinaryReader(stream);
if (br.ReadInt32() != WaveInterop.mmioStringToFOURCC("RIFF", 0))
{
throw new FormatException("Not a WAVE file - no RIFF header");
}
uint fileSize = br.ReadUInt32(); // read the file size (minus 8 bytes)
if (br.ReadInt32() != WaveInterop.mmioStringToFOURCC("WAVE", 0))
{
throw new FormatException("Not a WAVE file - no WAVE header");
}
int dataChunkID = WaveInterop.mmioStringToFOURCC("data", 0);
int formatChunkId = WaveInterop.mmioStringToFOURCC("fmt ", 0);
dataChunkLength = 0;
// sometimes a file has more data than is specified after the RIFF header
long stopPosition = Math.Min(fileSize + 8, stream.Length);
// this -8 is so we can be sure that there are at least 8 bytes for a chunk id and length
while (stream.Position <= stopPosition - 8)
{
Int32 chunkIdentifier = br.ReadInt32();
Int32 chunkLength = br.ReadInt32();
if (chunkIdentifier == dataChunkID)
{
dataChunkPosition = stream.Position;
dataChunkLength = chunkLength;
stream.Position += chunkLength;
}
else if (chunkIdentifier == formatChunkId)
{
format = WaveFormat.FromFormatChunk(br, chunkLength);
}
else
{
// check for invalid chunk length
if (chunkLength < 0 || chunkLength > stream.Length - stream.Position)
{
Debug.Assert(false, String.Format("Invalid chunk length {0}, pos: {1}. length: {2}",
chunkLength, stream.Position, stream.Length));
// an exception will be thrown further down if we haven't got a format and data chunk yet,
// otherwise we will tolerate this file despite it having corrupt data at the end
break;
}
if (chunks != null)
{
chunks.Add(new RiffChunk(chunkIdentifier, chunkLength, stream.Position));
}
stream.Position += chunkLength;
}
}
if (format == null)
{
throw new FormatException("Invalid WAV file - No fmt chunk found");
}
if (dataChunkPosition == -1)
{
throw new FormatException("Invalid WAV file - No data chunk found");
}
}
/// <summary>
/// Gets the cues as the concatenated cue and list RIFF chunks.
/// </summary>
/// <returns>RIFF chunks containing the cue data</returns>
internal byte[] GetRIFFChunks()
{
if (this.Count == 0)
{
return(null);
}
else
{
int cueChunkLength = 12 + 24 * this.Count;
int listChunkLength = 12;
int labelChunkLength = 0;
for (int i = 0; i < this.Count; i++)
{
labelChunkLength = this[i].Label.Length + 1;
listChunkLength += labelChunkLength + labelChunkLength % 2 + 12;
}
byte[] chunks = new byte[cueChunkLength + listChunkLength];
Int32 cueChunkID = WaveInterop.mmioStringToFOURCC("cue ", 0);
Int32 dataChunkID = WaveInterop.mmioStringToFOURCC("data", 0);
Int32 listChunkID = WaveInterop.mmioStringToFOURCC("LIST", 0);
Int32 adtlTypeID = WaveInterop.mmioStringToFOURCC("adtl", 0);
Int32 labelChunkID = WaveInterop.mmioStringToFOURCC("labl", 0);
using (MemoryStream stream = new MemoryStream(chunks))
{
using (BinaryWriter writer = new BinaryWriter(stream))
{
writer.Write(cueChunkID);
writer.Write(cueChunkLength - 8);
writer.Write(this.Count);
for (int cue = 0; cue < this.Count; cue++)
{
writer.Write(cue);
writer.Seek(4, SeekOrigin.Current);
writer.Write(dataChunkID);
writer.Seek(8, SeekOrigin.Current);
writer.Write(this[cue].Position);
}
writer.Write(listChunkID);
writer.Write(listChunkLength - 8);
writer.Write(adtlTypeID);
for (int cue = 0; cue < this.Count; cue++)
{
writer.Write(labelChunkID);
writer.Write(this[cue].Label.Length + 1 + 4);
writer.Write(cue);
writer.Write(Encoding.Default.GetBytes(this[cue].Label.ToCharArray()));
if (this[cue].Label.Length % 2 == 0)
{
writer.Seek(2, SeekOrigin.Current);
}
else
{
writer.Seek(1, SeekOrigin.Current);
}
}
}
}
return(chunks);
}
}