fileread.cpp

Mobile STK for Symbian OS V0.1

bool FileRead :: getAifInfo( const char *fileName )
{
  bool aifc = false;
  char id[4];

  // Determine whether this is AIFF or AIFC.
  if ( fseek(fd_, 8, SEEK_SET) == -1 ) goto error;
  if ( fread(&id, 4, 1, fd_) != 1 ) goto error;
  if ( !strncmp(id, "AIFC", 4) ) aifc = true;

  // Find "common" chunk
  SINT32 chunkSize;
  if ( fread(&id, 4, 1, fd_) != 1) goto error;
  while ( strncmp(id, "COMM", 4) ) {
    if ( fread(&chunkSize, 4, 1, fd_) != 1 ) goto error;
#ifdef __LITTLE_ENDIAN__
    swap32((unsigned char *)&chunkSize);
#endif
    chunkSize += chunkSize % 2; // chunk sizes must be even
    if ( fseek(fd_, chunkSize, SEEK_CUR) == -1 ) goto error;
    if ( fread(&id, 4, 1, fd_) != 1 ) goto error;
  }

  // Get number of channels from the header.
  SINT16 temp;
  if ( fseek(fd_, 4, SEEK_CUR) == -1 ) goto error; // Jump over chunk size
  if ( fread(&temp, 2, 1, fd_) != 1 ) goto error;
#ifdef __LITTLE_ENDIAN__
  swap16((unsigned char *)&temp);
#endif
  channels_ = temp;

  // Get length of data from the header.
  SINT32 frames;
  if ( fread(&frames, 4, 1, fd_) != 1 ) goto error;
#ifdef __LITTLE_ENDIAN__
  swap32((unsigned char *)&frames);
#endif
  fileSize_ = frames; // sample frames

  // Read the number of bits per sample.
  if ( fread(&temp, 2, 1, fd_) != 1 ) goto error;
#ifdef __LITTLE_ENDIAN__
  swap16((unsigned char *)&temp);
#endif

  // Get file sample rate from the header.  For AIFF files, this value
  // is stored in a 10-byte, IEEE Standard 754 floating point number,
  // so we need to convert it first.
  unsigned char srate[10];
  unsigned char exp;
  unsigned long mantissa;
  unsigned long last;
  if ( fread(&srate, 10, 1, fd_) != 1 ) goto error;
  mantissa = (unsigned long) *(unsigned long *)(srate+2);
#ifdef __LITTLE_ENDIAN__
  swap32((unsigned char *)&mantissa);
#endif
  exp = 30 - *(srate+1);
  last = 0;
  while (exp--) {
    last = mantissa;
    mantissa >>= 1;
  }
  if (last & 0x00000001) mantissa++;
  fileRate_ = (StkFloat) mantissa;

  // Determine the data format.
  dataType_ = 0;
  if ( aifc == false ) {
    if ( temp <= 8 ) dataType_ = STK_SINT8;
    else if ( temp <= 16 ) dataType_ = STK_SINT16;
    else if ( temp <= 24 ) dataType_ = STK_SINT24;
    else if ( temp <= 32 ) dataType_ = STK_SINT32;
  }
  else {
    if ( fread(&id, 4, 1, fd_) != 1 ) goto error;
    if ( !strncmp(id, "NONE", 4) ) {
      if ( temp <= 8 ) dataType_ = STK_SINT8;
      else if ( temp <= 16 ) dataType_ = STK_SINT16;
      else if ( temp <= 24 ) dataType_ = STK_SINT24;
      else if ( temp <= 32 ) dataType_ = STK_SINT32;
    }
    else if ( (!strncmp(id, "fl32", 4) || !strncmp(id, "FL32", 4)) && temp == 32 ) dataType_ = STK_FLOAT32;
    else if ( (!strncmp(id, "fl64", 4) || !strncmp(id, "FL64", 4)) && temp == 64 ) dataType_ = STK_FLOAT64;
  }
  if ( dataType_ == 0 ) {
#if !defined(SYMBIAN)
    errorString_ << "FileRead: AIFF/AIFC file (" << fileName << ") has unsupported data type (" << id << ").";
#endif
    return false;
  }

  // Start at top to find data (SSND) chunk ... chunk order is undefined.
  if ( fseek(fd_, 12, SEEK_SET) == -1 ) goto error;

  // Find data (SSND) chunk
  if ( fread(&id, 4, 1, fd_) != 1 ) goto error;
  while ( strncmp(id, "SSND", 4) ) {
    if ( fread(&chunkSize, 4, 1, fd_) != 1 ) goto error;
#ifdef __LITTLE_ENDIAN__
    swap32((unsigned char *)&chunkSize);
#endif
    chunkSize += chunkSize % 2; // chunk sizes must be even
    if ( fseek(fd_, chunkSize, SEEK_CUR) == -1 ) goto error;
    if ( fread(&id, 4, 1, fd_) != 1 ) goto error;
  }

  // Skip over chunk size, offset, and blocksize fields
  if ( fseek(fd_, 12, SEEK_CUR) == -1 ) goto error;

  dataOffset_ = ftell(fd_);
  byteswap_ = false;
#ifdef __LITTLE_ENDIAN__
  byteswap_ = true;
#endif

  return true;

 error:
#if !defined(SYMBIAN)
  errorString_ << "FileRead: Error reading AIFF file (" << fileName << ").";
#endif
  return false;
}

bool FileRead :: getMatInfo( const char *fileName )
{
  // MAT-file formatting information is available at:
  // http://www.mathworks.com/access/helpdesk/help/pdf_doc/matlab/matfile_format.pdf

  // Verify this is a version 5 MAT-file format.
  char head[4];
  if ( fseek(fd_, 0, SEEK_SET) == -1 ) goto error;
  if ( fread(&head, 4, 1, fd_) != 1 ) goto error;
  // If any of the first 4 characters of the header = 0, then this is
  // a Version 4 MAT-file.
  if ( strstr(head, "0") ) {
#if !defined(SYMBIAN)
    errorString_ << "FileRead: " << fileName << " appears to be a Version 4 MAT-file, which is not currently supported.";
#endif
    return false;
  }

  // Determine the endian-ness of the file.
  char mi[2];
  byteswap_ = false;
  // Locate "M" and "I" characters in header.
  if ( fseek(fd_, 126, SEEK_SET) == -1 ) goto error;
  if ( fread(&mi, 2, 1, fd_) != 1) goto error;
#ifdef __LITTLE_ENDIAN__
  if ( !strncmp(mi, "MI", 2) )
    byteswap_ = true;
  else if ( strncmp(mi, "IM", 2) ) goto error;
#else
  if ( !strncmp(mi, "IM", 2))
    byteswap_ = true;
  else if ( strncmp(mi, "MI", 2) ) goto error;
#endif

  // Check the data element type
  SINT32 datatype;
  if ( fread(&datatype, 4, 1, fd_) != 1 ) goto error;
  if ( byteswap_ ) swap32((unsigned char *)&datatype);
  if (datatype != 14) {
#if !defined(SYMBIAN)
    errorString_ << "FileRead: The file does not contain a single Matlab array (or matrix) data element.";
#endif
    return false;
  }

  // Determine the array data type.
  SINT32 tmp;
  SINT32 size;
  if ( fseek(fd_, 168, SEEK_SET) == -1 ) goto error;
  if ( fread(&tmp, 4, 1, fd_) != 1 ) goto error;
  if (byteswap_) swap32((unsigned char *)&tmp);
  if (tmp == 1) {  // array name > 4 characters
    if ( fread(&tmp, 4, 1, fd_) != 1 ) goto error;  // get array name length
    if (byteswap_) swap32((unsigned char *)&tmp);
    size = (SINT32) ceil((float)tmp / 8);
    if ( fseek(fd_, size*8, SEEK_CUR) == -1 ) goto error;  // jump over array name
  }
  else { // array name <= 4 characters, compressed data element
    if ( fseek(fd_, 4, SEEK_CUR) == -1 ) goto error;
  }
  if ( fread(&tmp, 4, 1, fd_) != 1 ) goto error;
  if (byteswap_) swap32((unsigned char *)&tmp);
  if ( tmp == 1 ) dataType_ = STK_SINT8;
  else if ( tmp == 3 ) dataType_ = STK_SINT16;
  else if ( tmp == 5 ) dataType_ = STK_SINT32;
  else if ( tmp == 7 ) dataType_ = STK_FLOAT32;
  else if ( tmp == 9 ) dataType_ = STK_FLOAT64;
  else {
#if !defined(SYMBIAN)
    errorString_ << "FileRead: The MAT-file array data format (" << tmp << ") is not supported.";
#endif
    return false;
  }

  // Get number of rows from the header.
  SINT32 rows;
  if ( fseek(fd_, 160, SEEK_SET) == -1 ) goto error;
  if ( fread(&rows, 4, 1, fd_) != 1 ) goto error;
  if (byteswap_) swap32((unsigned char *)&rows);

  // Get number of columns from the header.
  SINT32 columns;
  if ( fread(&columns, 4, 1, fd_) != 1 ) goto error;
  if (byteswap_) swap32((unsigned char *)&columns);

  // Assume channels = smaller of rows or columns.
  if (rows < columns) {
    channels_ = rows;
    fileSize_ = columns;
  }
  else {
#if !defined(SYMBIAN)
    errorString_ << "FileRead: Transpose the MAT-file array so that audio channels fill matrix rows (not columns).";
#endif
    return false;
  }

  // Move read pointer to the data in the file.
  SINT32 headsize;
  if ( fseek(fd_, 132, SEEK_SET) == -1 ) goto error;
  if ( fread(&headsize, 4, 1, fd_) != 1 ) goto error; // file size from 132nd byte
  if (byteswap_) swap32((unsigned char *)&headsize);
  headsize -= fileSize_ * 8 * channels_;
  if ( fseek(fd_, headsize, SEEK_CUR) == -1 ) goto error;
  dataOffset_ = ftell(fd_);

  // Assume MAT-files have 44100 Hz sample rate.
  fileRate_ = 44100.0;

  return true;

 error:
#if !defined(SYMBIAN)
  errorString_ << "FileRead: Error reading MAT-file (" << fileName << ").";
#endif
  return false;
}

void FileRead :: read( StkFrames& buffer, unsigned long startFrame, bool doNormalize )
{
  // Make sure we have an open file.
  if ( fd_ == 0 ) {
#if !defined(SYMBIAN)
    errorString_ << "FileRead::read: a file is not open!";
    Stk::handleError( StkError::WARNING );
#endif
    return;
  }

  // Check the buffer size.
  unsigned int nFrames = buffer.frames();
  if ( nFrames == 0 ) {
#if !defined(SYMBIAN)
    errorString_ << "FileRead::read: StkFrames buffer size is zero ... no data read!";
    Stk::handleError( StkError::WARNING );
#endif
    return;
  }

  if ( buffer.channels() != channels_ ) {
#if !defined(SYMBIAN)
    errorString_ << "FileRead::read: StkFrames argument has incompatible number of channels!";
    Stk::handleError( StkError::FUNCTION_ARGUMENT );
#endif
  }

  // Check for file end.
  if ( startFrame + nFrames >= fileSize_ )
    nFrames = fileSize_ - startFrame;

  long i, nSamples = (long) ( nFrames * channels_ );
  unsigned long offset = startFrame * channels_;

  // Read samples into StkFrames data buffer.
  if ( dataType_ == STK_SINT16 ) {
    SINT16 *buf = (SINT16 *) &buffer[0];
    if ( fseek( fd_, dataOffset_+(offset*2), SEEK_SET ) == -1 ) goto error;
    if ( fread( buf, nSamples * 2, 1, fd_ ) != 1 ) goto error;
    if ( byteswap_ ) {
      SINT16 *ptr = buf;
      for ( i=nSamples-1; i>=0; i-- )
        swap16( (unsigned char *) ptr++ );
    }
    if ( doNormalize ) {
      StkFloat gain = 1.0 / 32768.0;
      for ( i=nSamples-1; i>=0; i-- )
        buffer[i] = buf[i] * gain;
    }
    else {
      for ( i=nSamples-1; i>=0; i-- )
        buffer[i] = buf[i];
    }
  }
  else if ( dataType_ == STK_SINT32 ) {
    SINT32 *buf = (SINT32 *) &buffer[0];
    if ( fseek( fd_, dataOffset_+(offset*4 ), SEEK_SET ) == -1 ) goto error;
    if ( fread( buf, nSamples * 4, 1, fd_ ) != 1 ) goto error;
    if ( byteswap_ ) {
      SINT32 *ptr = buf;
      for ( i=nSamples-1; i>=0; i-- )
        swap32( (unsigned char *) ptr++ );
    }
    if ( doNormalize ) {
      StkFloat gain = 1.0 / 2147483648.0;
      for ( i=nSamples-1; i>=0; i-- )
        buffer[i] = buf[i] * gain;
    }
    else {
      for ( i=nSamples-1; i>=0; i-- )
        buffer[i] = buf[i];
    }
  }
  else if ( dataType_ == STK_FLOAT32 ) {
    FLOAT32 *buf = (FLOAT32 *) &buffer[0];
    if ( fseek( fd_, dataOffset_+(offset*4), SEEK_SET ) == -1 ) goto error;
    if ( fread( buf, nSamples * 4, 1, fd_ ) != 1 ) goto error;
    if ( byteswap_ ) {
      FLOAT32 *ptr = buf;
      for ( i=nSamples-1; i>=0; i-- )
        swap32( (unsigned char *) ptr++ );
    }
    for ( i=nSamples-1; i>=0; i-- )
      buffer[i] = buf[i];
  }
  else if ( dataType_ == STK_FLOAT64 ) {
    FLOAT64 *buf = (FLOAT64 *) &buffer[0];
    if ( fseek( fd_, dataOffset_+(offset*8), SEEK_SET ) == -1 ) goto error;
    if ( fread( buf, nSamples * 8, 1, fd_ ) != 1 ) goto error;
    if ( byteswap_ ) {
      FLOAT64 *ptr = buf;
      for ( i=nSamples-1; i>=0; i-- )
        swap64( (unsigned char *) ptr++ );
    }
    for ( i=nSamples-1; i>=0; i-- )
      buffer[i] = buf[i];
  }
  else if ( dataType_ == STK_SINT8 && wavFile_ ) { // 8-bit WAV data is unsigned!
    unsigned char *buf = (unsigned char *) &buffer[0];
    if ( fseek( fd_, dataOffset_+offset, SEEK_SET ) == -1 ) goto error;
    if ( fread( buf, nSamples, 1, fd_) != 1 ) goto error;
    if ( doNormalize ) {
      StkFloat gain = 1.0 / 128.0;
      for ( i=nSamples-1; i>=0; i-- )
        buffer[i] = ( buf[i] - 128 ) * gain;
    }
    else {
      for ( i=nSamples-1; i>=0; i-- )
        buffer[i] = buf[i] - 128.0;
    }
  }
  else if ( dataType_ == STK_SINT8 ) { // signed 8-bit data
    char *buf = (char *) &buffer[0];
    if ( fseek( fd_, dataOffset_+offset, SEEK_SET ) == -1 ) goto error;
    if ( fread( buf, nSamples, 1, fd_ ) != 1 ) goto error;
    if ( doNormalize ) {
      StkFloat gain = 1.0 / 128.0;
      for ( i=nSamples-1; i>=0; i-- )
        buffer[i] = buf[i] * gain;
    }
    else {
      for ( i=nSamples-1; i>=0; i-- )
        buffer[i] = buf[i];
    }
  }
  else if ( dataType_ == STK_SINT24 ) {
    // 24-bit values are harder to import efficiently since there is
    // no native 24-bit type.  The following routine works but is much
    // less efficient that that used for the other data types.
    SINT32 buf;
    StkFloat gain = 1.0 / 8388608.0;
    if ( fseek(fd_, dataOffset_+(offset*3), SEEK_SET ) == -1 ) goto error;
    for ( i=0; i<nSamples; i++ ) {
      if ( fread( &buf, 3, 1, fd_ ) != 1 ) goto error;
      buf >>= 8;
      if ( byteswap_ )
        swap32( (unsigned char *) &buf );
      if ( doNormalize )
        buffer[i] = buf * gain;
      else
        buffer[i] = buf;
    }
  }

  buffer.setDataRate( fileRate_ );

  return;

 error:
#if !defined(SYMBIAN)
  errorString_ << "FileRead: Error reading file data.";
  handleError( StkError::FILE_ERROR);
#else
  {}
#endif
}

// #endif // SYMBIAN