public WaveReader(string file_name)
{
int i;
BinaryReader fw;
WaveHeader wav;
ChunkHeader chk;
int sflag;
int rmore;
char[] wbuff;
int wbuff_len;
// set defaults
g_wdata_in = null;
g_num_isamp = 0;
g_max_isamp = 0;
// allocate wav header
wav = new WaveHeader();
chk = new ChunkHeader();
// # open wav file
fw = new BinaryReader(File.OpenRead(file_name));
// # read riff/wav header
wav.ReadFromStream(fw);
// # check format of header
//if (strcmp(obuff, "RIFF") != 0) exit_msg(-587, "bad RIFF format");
if (!wav.rID.Equals("RIFF"))
{
throw new Exception("bad RIFF format");
}
//if (strcmp(obuff, "WAVE") != 0) exit_msg(-587, "bad WAVE format");
if (!wav.wID.Equals("WAVE"))
{
throw new Exception("bad WAVE format");
}
//if (strcmp(obuff, "fmt") != 0) exit_msg(-587, "bad fmt format");
if (!wav.fId.Equals("fmt "))
{
throw new Exception("bad fmt format");
}
//if (wav->wFormatTag != 1) exit_msg(-587, "bad wav wFormatTag");
if (wav.wFormatTag != 1)
{
throw new Exception("bad wav wFormatTag");
}
//if ((wav->nBitsPerSample != 16) && (wav->nBitsPerSample != 8)) exit_msg(-587, "bad wav stuff");
if (wav.nBitsPerSample != 16 && wav.nBitsPerSample != 8)
{
throw new Exception("bad wav nBitsPerSample");
}
// skip over any remaining portion of wav header
rmore = wav.pcm_header_len - (Marshal.SizeOf(typeof(WaveHeader)) - 20);
fw.ReadBytes(rmore);
// read chunks until a 'data' chunk is found
sflag = 1;
while (sflag != 0)
{
// check attempts
if (sflag > 10)
{
throw new Exception("too many chunks");
}
// read chunk header
chk.ReadFromStream(fw);
// check chunk type
if (chk.dId.Equals("data"))
{
break;
}
// skip over chunk
fw.ReadBytes(chk.dLen);
// increment the size flag
sflag++;
}
/* find length of remaining data */
wbuff_len = chk.dLen;
// find number of samples
g_max_isamp = chk.dLen;
g_max_isamp /= wav.nBitsPerSample / 8;
/* allocate new buffers */
wbuff = new char[wbuff_len];
// if(g_wdata_in!=NULL) delete g_wdata_in;
g_wdata_in = new double[g_max_isamp];
/* read signal data */
wbuff = fw.ReadChars(wbuff_len);
// convert data
if (wav.nBitsPerSample == 16)
{
for (i = 0; i < g_max_isamp; i++)
{
g_wdata_in[i] = (double)((ushort)(wbuff[i]));
}
}
else
{
for (i = 0; i < g_max_isamp; i++)
{
g_wdata_in[i] = (double)((byte)(wbuff[i]));
}
}
// save demographics
fs_hz = (double)(wav.nSamplesPerSec);
bits_per_sample = wav.nBitsPerSample;
num_ch = wav.nChannels;
// reset buffer stream index
g_num_isamp = 0;
// be polite - clean up
fw.Close();
}
