//dataChunk ReadDataHeader() - 2004 July 28
//Again, not much to say.
public dataChunk ReadDataHeader()
{
data = new dataChunk();
data.sChunkID = "data";
data.dwChunkSize = reader.ReadUInt32();
data.lFilePosition = reader.BaseStream.Position;
if (fact != null)
{
data.dwNumSamples = fact.dwNumSamples;
}
else
{
data.dwNumSamples = data.dwChunkSize / (format.dwBitsPerSample / 8 * format.wChannels);
}
//The above could be written as data.dwChunkSize / format.wBlockAlign, but I want to emphasize what the frames look like.
data.dwMinLength = (data.dwChunkSize / format.dwAvgBytesPerSec) / 60;
data.dSecLength = ((double)data.dwChunkSize / (double)format.dwAvgBytesPerSec) - (double)data.dwMinLength * 60;
return(data);
}
public WaveFile(string filename)
{
reader = new WaveFileReader(filename);
maindata = reader.ReadMainFileHeader();
maindata.FileName = filename;
long chunkSize = 0;
string chunkName = null;
while (chunkName != "data" && reader.GetPosition() < (long)maindata.dwFileLength && reader.GetPosition() + chunkSize < maindata.dwFileLength)
{
chunkName = reader.GetChunkName();
switch (chunkName)
{
case "fmt ":
format = reader.ReadFormatHeader();
chunkSize = format.dwChunkSize;
break;
case "fact":
fact = reader.ReadFactHeader();
chunkSize = fact.dwChunkSize;
break;
case "data":
data = reader.ReadDataHeader();
chunkSize = data.dwChunkSize;
break;
default:
//This provides the required skipping of unsupported chunks.
// reader.AdvanceToNext();
chunkSize = 0;
break;
}
}
}
