// for now assume 16-bit LE PCM, reinterleavein towav output
public static void InterleaveRiffToWavOutputFiles(string[] inputFiles, string outputFile,
InterleaveRiffFilesOptionsStruct interleaveOptions)
{
// verify that two or more files have been input
if (inputFiles.Length < 2)
{
throw new Exception("More than one file must be input for interleaving.");
}
// verify features match
if (!inputFilesHaveEqualFeatures(inputFiles))
{
throw new Exception("Input files must have same channel count and frequency.");
}
// interleave data
interleaveDataChunks(inputFiles, outputFile, interleaveOptions);
// update RIFF header
}
private static string interleaveDataChunks(string[] inputFiles, string outputFile,
InterleaveRiffFilesOptionsStruct interleaveOptions)
{
Dictionary <int, FileStream> inputFileHash = new Dictionary <int, FileStream>();
FileStream outputStream = null;
string interleavedFilePath = String.Format("{0}.interleaved.data{1}",
Path.GetFileNameWithoutExtension(outputFile),
Path.GetExtension(outputFile));
uint maxDataSize = 0;
uint bytesProcessed = 0;
byte[] bytes = new byte[2];
int bytesRead;
uint[] dataSizes = new uint[inputFiles.Length];
long[] dataStartOffset = new long[inputFiles.Length];
long[] fileSizes = new long[inputFiles.Length];
try
{
// open file streams and get data location info
for (int i = 0; i < inputFiles.Length; i++)
{
using (FileStream fs = File.OpenRead(inputFiles[i]))
{
inputFileHash.Add(i, fs);
dataSizes[i] = GetDataSizeFromRiffHeader(inputFileHash[i]);
dataStartOffset[i] = GetDataStartOffsetFromRiffHeader(inputFileHash[i]);
fileSizes[i] = inputFileHash[i].Length;
if (dataSizes[i] > maxDataSize)
{
maxDataSize = dataSizes[i];
}
}
}
// write output file (16-bit LE PCM assumed)
using (outputStream = File.OpenWrite(interleavedFilePath))
{
// move to data section
for (int i = 0; i < inputFiles.Length; i++)
{
inputFileHash[i].Position = dataStartOffset[i];
}
// write to file
while (bytesProcessed <= maxDataSize)
{
for (int i = 0; i < inputFiles.Length; i++)
{
// read bytes
bytesRead = inputFileHash[i].Read(bytes, 0, 2);
// insert filler bytes
for (int j = bytesRead; j < 2; j++)
{
bytes[j] = interleaveOptions.FillerByte;
}
// write bytes to output file
outputStream.Write(bytes, 0, 2);
}
bytesProcessed += 2;
}
}
}
finally
{
// close all streams
foreach (int k in inputFileHash.Keys)
{
if ((inputFileHash[k] != null) &&
(inputFileHash[k].CanRead))
{
inputFileHash[k].Close();
inputFileHash[k].Dispose();
}
}
if ((outputStream != null) &&
(outputStream.CanWrite))
{
outputStream.Close();
outputStream.Dispose();
}
}
return(interleavedFilePath);
}
