stk/MatWvOut.cpp

/*******************************************/
/*  Matlab MAT File Output Class,          */
/*  by Gary P. Scavone, 1998.              */
/*  This object creates a Matlab MAT-file  */
/*  structure and fills it with buffers of */
/*  samples (doubles).                     */
/*                                         */
/*  The Matlab MAT-file format is not      */
/*  available to the general public.  I    */
/*  spent several days reverse-engineering */
/*  the file format to create this class.  */
/*  I couldn't figure out what a few of    */
/*  the header fields correspond to, but   */
/*  for the purposes of STK, this          */
/*  shouldn't create any problems.         */
/*******************************************/

#include "MatWvOut.h"

/********  Matlab Matfile Header Struct   *******/
struct matheaderform {
  char heading[124];
  short a[2];
  long b[10];
  /* There's more, but it's of variable length */
};

FILE *openMatFile(int chans,char *fileName)	{
  struct matheaderform hdr;
  FILE *fd;
  char tempName[128];
  int i, namelen;
  long longtmp, headsize;

  strcpy(hdr.heading,"MATLAB 5.0 MAT-file, Generated by STK98. This file format was hacked by Gary P. Scavone, CCRMA, Stanford University, 1998.");

  for (i=strlen(hdr.heading);i<124;i++) hdr.heading[i] = ' ';

  hdr.a[0] = (short) 256;
  hdr.a[1] = (short) 'M';
  hdr.a[1] <<= 8;
  hdr.a[1] += 'I';
  hdr.b[0] = (long) 14;
  hdr.b[1] = (long) 0; /* Size of file after this point to end (in bytes) */
  hdr.b[2] = (long) 6;
  hdr.b[3] = (long) 8;
  hdr.b[4] = (long) 6;
  hdr.b[5] = (long) 0;
  hdr.b[6] = (long) 5;
  hdr.b[7] = (long) 8;
  hdr.b[8] = (long) chans; /* This is the number of rows */
  hdr.b[9] = (long) 0; /* This is the number of columns */

  strcpy(tempName,fileName);
  strcat(tempName,".mat");

  fd = fopen(tempName,"w+b");
  if (!fd)   {
    printf("Couldn't create matfile %s  !!!!!!!!\n",fileName);
    exit(0);
  }

  printf("Creating matfile %s.\n", tempName);
  fwrite(&hdr,sizeof(char),168,fd); /* Write the fixed portion of the header */

  /* The next 4 bytes can be viewed as two shorts, but they are byteswapped
     as a long.  The first short value seems to always be one; the second
     short will be the length of the variable name IF IT IS <= 4; if the
     variable name length is >4, this short is zero and the length is put
     in the next 4 bytes.  The variable name length is limited to 31
     characters (32 with a '\n'). The actual variable name then follows.
     The variable name is "zero-padded" out to the following minimum
     lengths (in bits): 4, 8, 16, 24, 32.
  */
  namelen = strlen(fileName);
  if (namelen > 31) { /* Check length of variable name (file name) */
    fprintf(stderr, "File name too long ... should be 31 characters or less.\n");
    fclose(fd);
    exit(0);
  }

  if (namelen > 4) {
    longtmp = 1;
    fwrite(&longtmp,sizeof(long),1,fd);
    fwrite(&namelen,sizeof(long),1,fd);
    headsize = 44 + namelen;
  } else {
    longtmp = namelen;
    longtmp <<= 16;
    longtmp += 1;
    fwrite(&longtmp,sizeof(long),1,fd);
    headsize = 40 + namelen;
  }

  fwrite(fileName,sizeof(char),namelen,fd); /* Write the variable (file) name */
  if (namelen < 5)
    longtmp = 4 - namelen;
  else if (namelen < 9)
    longtmp = 8 - namelen;
  else if (namelen < 17)
    longtmp = 16 - namelen;
  else if (namelen < 25)
    longtmp = 24 - namelen;
  else longtmp = 32 - namelen;

  headsize += longtmp + 8; /* Add length (8) of following bytes */
  fseek(fd,longtmp,SEEK_CUR);

  longtmp = 9;
  fwrite(&longtmp,sizeof(long),1,fd);
  longtmp = 0; /* Size of data in bytes (8 per sample) */
  fwrite(&longtmp,sizeof(long),1,fd);

  fseek(fd,132,SEEK_SET);
  fwrite(&headsize,sizeof(long),1,fd); /* Write header size ... will update at end */
  fseek(fd,0,SEEK_END);

  return fd;
}

MatWvOut :: MatWvOut(char *fileName)
{
  chans = 1;
  pan = 0.5;
  fd = openMatFile(chans,fileName);
  counter = 0;
  totalCount = 0;
}

MatWvOut :: MatWvOut(int channels, char *fileName)
{
  chans = channels;
  pan = 0.5;
  fd = openMatFile(chans,fileName);
  counter = 0;
  totalCount = 0;
}

MatWvOut :: ~MatWvOut()
{
  double temp;
  long headsize, temp1;

  fwrite(data,sizeof(double),counter,fd);
  temp = (double) totalCount * ONE_OVER_SRATE;
  printf("%f Seconds Computed\n",temp);
  fseek(fd,164,SEEK_SET);
  fwrite(&totalCount,sizeof(long),1,fd); /* Write number of columns */
  fseek(fd,132,SEEK_SET);
  fread(&headsize,sizeof(long),1,fd);
  temp1 = headsize;
  headsize += (long) (totalCount * 8 * 2);
  fseek(fd,132,SEEK_SET);
  fwrite(&headsize,sizeof(long),1,fd); /* Write file size (minus some header info) */
  fseek(fd,temp1+128,SEEK_SET);
  temp1 = totalCount * 8 * 2;
  fwrite(&temp1,sizeof(long),1,fd); /* Write data size (in bytes) */
  fclose(fd);
}

long MatWvOut :: getCounter()
{
  return totalCount;
}

MY_FLOAT MatWvOut :: getTime()
{
  return (MY_FLOAT) totalCount * ONE_OVER_SRATE;
}

void MatWvOut :: tick(MY_FLOAT sample)
{
  if (chans==1)	{
    data[counter++] = (double) (sample);
  }
  else 	{
    data[counter++] = (double) (sample * (1.0 - pan));
    data[counter++] = (double) (sample * pan);
  }
  totalCount += 1;
  if (counter == MAT_BUFFER_SIZE) {
    fwrite(data,sizeof(double),MAT_BUFFER_SIZE,fd);
    counter = 0;
  }
}

void MatWvOut :: tick(MY_FLOAT lsamp, MY_FLOAT rsamp)
{
  if (chans==1)	{
    data[counter++] = (double) (lsamp + rsamp);
  }
  else 	{
    data[counter++] = (double) (lsamp);
    data[counter++] = (double) (rsamp);
  }
  totalCount += 1;
  if (counter == MAT_BUFFER_SIZE) {
    fwrite(data,sizeof(double),MAT_BUFFER_SIZE,fd);
    counter = 0;
  }
}

void MatWvOut :: setMonoPan(MY_FLOAT aPan)
{
  pan = aPan;
  if (aPan < 0.0) {
    pan = 0.0;
    printf("Pan < 0.0, correcting to 0.0\n");
  }
  if (aPan > 1.0) {
    pan = 1.0;
    printf("Pan > 1.0, correcting to 1.0\n");
  }
}