long audiofile_header_extractor(FILE *inputfile, float *SR, unsigned int *nbchan, unsigned int *depth, unsigned char *isfloat, unsigned char *isbigendian, unsigned int *frames)
{
unsigned char FileHead[12], WavTemp[8], *aChunk, AIFCflag;
unsigned int n;
long index = -1;
// checks the file is a legit AIFF or WAV by importing the header
fread(FileHead, 1, 12, inputfile);
//selects aiff or aifc
if (strncmp((char *)FileHead, "FORM", 4) == 0)
{
//check if 'only' an AIFF
if (strncmp((char *)FileHead+8, "AIFF", 4) == 0)
AIFCflag = 0;
else if (strncmp((char *)FileHead+8, "AIFC", 4) == 0)
AIFCflag = 1;
else
{
// printf("this is an unknown AIFx\r");
return -1;
}
//check for the different headers and size
while(fread(WavTemp, 1, 8, inputfile))
{
n = (unsigned int)WavTemp[4]<<24 | (unsigned int)WavTemp[5]<<16 | (unsigned int)WavTemp[6]<<8 | (unsigned int)WavTemp[7];
//the version header
if (strncmp((char *)WavTemp, "FVER", 4) == 0)
{
aChunk = malloc(n);
fread(aChunk, 1, n, inputfile);
n = (unsigned int)aChunk[0]<<24 | (unsigned int)aChunk[1]<<16 | (unsigned int)aChunk[2]<<8 | (unsigned int)aChunk[3];
if (n != 0xA2805140)
{
// printf("wrong version of AIFC\r");
free(aChunk);
return -2;
}
free(aChunk);
}
// the common header
else if (strncmp((char *)WavTemp, "COMM", 4) == 0)
{
aChunk = malloc(n);
fread(aChunk, 1, n, inputfile);
*nbchan = (unsigned int)aChunk[0]<<8 | (unsigned int)aChunk[1];
*depth = ((unsigned int)aChunk[6]<<8 | (unsigned int)aChunk[7]) / 8;
*isfloat = 0; // in case of AIFF
*isbigendian = 1; // in case of AIFF
*frames = (unsigned int)aChunk[2]<<24 | (unsigned int)aChunk[3]<<16 | (unsigned int)aChunk[4]<<8 | (unsigned int)aChunk[5];
//type of compression accepted (none or float32)
// if aifc it can be float
if (AIFCflag)
{
if (strncmp((char *)aChunk+18, "NONE", 4) == 0)
*isfloat = 0;//could do nothing here but gotta keep the place neet.
else if (strncmp((char *)aChunk+18, "sowt", 4) == 0)
*isbigendian = 0;//the few little endian cases
else if (strncmp((char *)aChunk+18, "fl32", 4) == 0 || strncmp((char *)aChunk+18, "FL32", 4) == 0)
*isfloat = 1;
else
{
// printf("neither PCM-int or FL32 AIFC\r");
free(aChunk);
return -3;
}
}
// converts the sampling rate 80bit to double
// tried with http://blogs.perl.org/users/rurban/2012/09/reading-binary-floating-point-numbers-numbers-part2.html but was not working. Found the old apple conversion routine
*SR = _af_convert_from_ieee_extended((unsigned char *)aChunk+8);
free(aChunk);
}
else if (strncmp((char *)WavTemp, "SSND", 4) == 0)
{
index = ftell(inputfile) + 8;// pass the index where the audio frames start (offset of 8 because of unused (unsigned long)offset + blockSize)
fseek(inputfile, n, SEEK_CUR);
}
else
// jumps the chunk
fseek(inputfile, n, SEEK_CUR);
}
if (!frames)
{
// printf("no data\r");
return -4;
}
}
// OR checks the file is a legit WAV and process
else if (strncmp((char *)FileHead, "RIF", 3) == 0)
{
if (FileHead[3] == 'F')
*isbigendian = 0;
else if (FileHead[3] == 'X')
*isbigendian = 1;//the very rare RIFX files
else
{
// printf("NoWAVE-at-all\r");
return -5;
}
if (strncmp((char *)FileHead+8, "WAVE", 4))
{
// printf("NoWAVE\r");
return -6;
}
// check the different parameters
// imports the first chunk + the header of the 2nd
fread(WavTemp, 1, 8, inputfile);
//check proper header
if (strncmp((char *)WavTemp, "fmt ", 4))
{
// printf("NoFMT\r");
return -7;
}
n = (unsigned int)WavTemp[7]<<24 | (unsigned int)WavTemp[6]<<16 | (unsigned int)WavTemp[5]<<8 | (unsigned int)WavTemp[4];
// import the rest of the format chunk
aChunk= malloc(n);
fread(aChunk, 1, n, inputfile);
//check if PCM or float
if (aChunk[1]== 0)
{
//safety check the datachunk
//transfer useful data from the chunk
*nbchan = (unsigned int)aChunk[3]<<8 | (unsigned int)aChunk[2];
*SR = (double)((unsigned int)aChunk[7]<<24 | (unsigned int)aChunk[6]<<16 | (unsigned int)aChunk[5]<<8 | (unsigned int)aChunk[4]);
*depth = ((unsigned int)aChunk[15]<<8 | (unsigned int)aChunk[14]) / 8;
free(aChunk);
// IF PCM or FLOAT
if (aChunk[0] == 1)
*isfloat = 0;
// IF FLOAT
else if (aChunk[0] == 3)
*isfloat = 1;
else
{
// printf("NoINTofFLOAT\r");
return -8;
}
while(fread(WavTemp, 1, 8, inputfile))
{
n = (unsigned int)WavTemp[7]<<24 | (unsigned int)WavTemp[6]<<16 | (unsigned int)WavTemp[5]<<8 | (unsigned int)WavTemp[4];
//looking for the data header
if (strncmp((char *)WavTemp, "data", 4) == 0)
{
*frames = ((unsigned int)WavTemp[7]<<24 | (unsigned int)WavTemp[6]<<16 | (unsigned int)WavTemp[5]<<8 | (unsigned int)WavTemp[4]) / *depth / *nbchan;
index = ftell(inputfile);// sets the index where the sound frames start
fseek(inputfile, n, SEEK_CUR);
}
else
fseek(inputfile, n, SEEK_CUR);
}
if (!frames)
{
// printf("no data\r");
return -9;
}
}
else
{
// printf("NoPCM\r");
free(aChunk);
return -8;
}
}
else
{
// OR discarts
// printf("Not a supported filetype\r");
return -10;
}
return index;
}
/*
Parse common data chunks, which contain information regarding the
sampling rate, the number of sample frames, and the number of
sound channels.
*/
static status ParseCOMM (AFfilehandle file, AFvirtualfile *fh, u_int32_t type,
size_t size)
{
_Track *track;
u_int16_t numChannels;
u_int32_t numSampleFrames;
u_int16_t sampleSize;
unsigned char sampleRate[10];
assert(!memcmp(&type, "COMM", 4));
track = _af_filehandle_get_track(file, AF_DEFAULT_TRACK);
af_fread(&numChannels, sizeof (u_int16_t), 1, fh);
track->f.channelCount = BENDIAN_TO_HOST_INT16(numChannels);
af_fread(&numSampleFrames, sizeof (u_int32_t), 1, fh);
track->totalfframes = BENDIAN_TO_HOST_INT32(numSampleFrames);
af_fread(&sampleSize, sizeof (u_int16_t), 1, fh);
track->f.sampleWidth = BENDIAN_TO_HOST_INT16(sampleSize);
af_fread(sampleRate, 10, 1, fh);
track->f.sampleRate = _af_convert_from_ieee_extended(sampleRate);
track->f.compressionType = AF_COMPRESSION_NONE;
track->f.sampleFormat = AF_SAMPFMT_TWOSCOMP;
track->f.byteOrder = AF_BYTEORDER_BIGENDIAN;
if (file->fileFormat == AF_FILE_AIFFC)
{
u_int8_t compressionID[4];
/* Pascal strings are at most 255 bytes long. */
unsigned char compressionName[256];
unsigned char compressionNameLength;
af_fread(compressionID, 4, 1, fh);
/* Read the Pascal-style string containing the name. */
af_fread(&compressionNameLength, 1, 1, fh);
af_fread(compressionName, compressionNameLength, 1, fh);
compressionName[compressionNameLength] = '\0';
if (!memcmp(compressionID, "NONE", 4))
track->f.compressionType = AF_COMPRESSION_NONE;
else if (!memcmp(compressionID, "ACE2", 4) ||
!memcmp(compressionID, "ACE8", 4) ||
!memcmp(compressionID, "MAC3", 4) ||
!memcmp(compressionID, "MAC6", 4))
{
_af_error(AF_BAD_NOT_IMPLEMENTED, "AIFF-C format does not support Apple's proprietary %s compression format", compressionName);
return AF_FAIL;
}
else if (!memcmp(compressionID, "ulaw", 4) ||
!memcmp(compressionID, "ULAW", 4))
{
track->f.compressionType = AF_COMPRESSION_G711_ULAW;
}
else if (!memcmp(compressionID, "alaw", 4) ||
!memcmp(compressionID, "ALAW", 4))
{
track->f.compressionType = AF_COMPRESSION_G711_ALAW;
}
else if (!memcmp(compressionID, "fl32", 4) ||
!memcmp(compressionID, "FL32", 4))
{
track->f.sampleFormat = AF_SAMPFMT_FLOAT;
track->f.sampleWidth = 32;
track->f.compressionType = AF_COMPRESSION_NONE;
}
else if (!memcmp(compressionID, "fl64", 4) ||
!memcmp(compressionID, "FL64", 4))
{
track->f.sampleFormat = AF_SAMPFMT_DOUBLE;
track->f.sampleWidth = 64;
track->f.compressionType = AF_COMPRESSION_NONE;
}
else if (!memcmp(compressionID, "sowt", 4))
{
track->f.compressionType = AF_COMPRESSION_NONE;
track->f.byteOrder = AF_BYTEORDER_LITTLEENDIAN;
}
else
{
_af_error(AF_BAD_NOT_IMPLEMENTED, "AIFF-C compression type '%c%c%c%c' not currently supported",
compressionID[0],
compressionID[1],
compressionID[2],
compressionID[3]);
return AF_FAIL;
}
}
_af_set_sample_format(&track->f, track->f.sampleFormat, track->f.sampleWidth);
return AF_SUCCEED;
}
