unsigned long val = 0;   unsigned char byte;   unsigned char bytes[2048];	/* bytes of an MPEG-2 extention frame */   long sync = EXT_SYNCWORD;		/* sync word maximum 32 bits */   int N = SYNC_WORD_LNGTH;	/* sync word length */   int i, sync_bytes = N / 8;   int nbytes, lcrc, la_bytes, la_bits;   if (fread (bytes, 1, 5, bs->pt) != 5)   {      printf ("next ext header not found\n");      return (0);   }   for (i = 0; i < sync_bytes; i++)   {      val <<= 8;      val |= bytes[i];   }   if ((N % 8) != 0)   {      val <<= N % 8;      byte = bytes[sync_bytes] >> (8 - (N % 8));      val |= byte;   }     if (val != sync)   {      printf ("no ext sync found: %4x\n", val);      return (0);   }   nbytes = (((int) (bytes[3] & 0x0f) * 256) + bytes[4]) / 2;   if (fread (&bytes[5], 1, nbytes-5, bs->pt) != nbytes-5)      return (0);   bytes_to_bits (bs->bits, bytes, nbytes);   bs->totbits = nbytes * 8;   bs->curpos = 12;   bs->eobs = 0;   info->ext_crc_check = getbits (bs, 16);   info->ext_length = getbits (bs, 11);   info->reserved_bit = get1bit (bs);#ifdef EXTENSION_CRC_CHECK   lcrc = info->ext_length * 8 - 28;   if (lcrc > 128) lcrc = 128;   la_bytes = (lcrc - 12) / 8;   la_bits = (lcrc - 12) % 8;   for (i = 0; i < la_bytes; i++)      info->ext_crc_bits[i] = getbits (bs, 8);   info->ext_crc_bits[la_bytes] = getbits (bs, la_bits);   bs->curpos = 40;   if (mc_ext_error_check (fr_ps, la_bytes, la_bits) == 0)      return (0);#endif   return (1);}/*******************************************************************************  End of bit_stream.c package******************************************************************************//*******************************************************************************  CRC error protection package******************************************************************************/void update_CRC(unsigned int data,		unsigned int length,		unsigned int *crc){	unsigned int  masking, carry;	masking = 1 << length;	while((masking >>= 1)){			carry = *crc & 0x8000;			*crc <<= 1;			if (!carry ^ !(data & masking))					*crc ^= CRC16_POLYNOMIAL;	}	*crc &= 0xffff;#ifdef	PrintCRCDebug	printf ("crc_len: %2d code: %4x crc: %4x\n", length, data, *crc);	fflush (stdout);#endif}void I_CRC_calc (frame_params *fr_ps,		 unsigned int bit_alloc[7][SBLIMIT], 		 unsigned int *crc){   int i, k;   layer *info = fr_ps->header;   int stereo  = fr_ps->stereo;   int jsbound = fr_ps->jsbound;   *crc = 0xffff; /* changed from '0' 92-08-11 shn */   update_CRC (info->bitrate_index, 4, crc);   update_CRC (info->sampling_frequency, 2, crc);   update_CRC (info->padding, 1, crc);   update_CRC (info->extension, 1, crc);   update_CRC (info->mode, 2, crc);   update_CRC (info->mode_ext, 2, crc);   update_CRC (info->copyright, 1, crc);   update_CRC (info->original, 1, crc);   update_CRC (info->emphasis, 2, crc);   for (i=0; i<SBLIMIT; i++)      for (k=0; k<((i<jsbound)?stereo:1); k++)	 update_CRC (bit_alloc[k][i], 4, crc);}void II_CRC_calc(frame_params *fr_ps,		 unsigned int bit_alloc[7][SBLIMIT], 		 unsigned int scfsi[7][SBLIMIT],		 unsigned int *crc){   int i, k;   layer *info = fr_ps->header;   int stereo  = fr_ps->stereo;   int sblimit = fr_ps->sblimit;   int jsbound = fr_ps->jsbound;   al_table *alloc = fr_ps->alloc;   *crc = 0xffff; /* changed from '0' 92-08-11 shn */   update_CRC (info->bitrate_index, 4, crc);   update_CRC (info->sampling_frequency, 2, crc);   update_CRC (info->padding, 1, crc);   update_CRC (info->extension, 1, crc);   update_CRC (info->mode, 2, crc);   update_CRC (info->mode_ext, 2, crc);   update_CRC (info->copyright, 1, crc);   update_CRC (info->original, 1, crc);   update_CRC (info->emphasis, 2, crc);   for (i=0; i<sblimit; i++)      for (k=0; k<((i<jsbound)?stereo:1); k++)	 update_CRC (bit_alloc[k][i], (*alloc)[i][0].bits, crc);   for (i=0; i<sblimit; i++)      for (k=0; k<stereo; k++)	 if (bit_alloc[k][i])	    update_CRC (scfsi[k][i], 2, crc);}void mc_error_check(frame_params *fr_ps,		    unsigned int bit_alloc[7][SBLIMIT], 		    unsigned int scfsi[7][SBLIMIT],		    unsigned int *crc,			     int ch_start,			     int channels){	 int i, m, l, pci,c,sbgr;	 layer *info = fr_ps->header;	 int sblimit = fr_ps->sblimit_mc;	 al_table *alloc = fr_ps->alloc_mc;	 *crc = 0xffff; /* changed from '0' 92-08-11 shn */	 update_CRC(info->ext_bit_stream_present, 1, crc);	 if ( info->ext_bit_stream_present == 1)		update_CRC(info->n_ad_bytes, 8, crc);	 update_CRC(info->center, 2, crc);	 update_CRC(info->surround, 2, crc);	 update_CRC(info->lfe, 1, crc);	 update_CRC(info->audio_mix, 1,crc);	 update_CRC(info->dematrix_procedure, 2, crc);	 update_CRC(info->no_of_multi_lingual_ch, 3, crc);	 update_CRC(info->multi_lingual_fs, 1, crc);	 update_CRC(info->multi_lingual_layer, 1, crc);	 update_CRC(info->copyright_ident_bit, 1, crc);	 update_CRC(info->copyright_ident_start, 1, crc);	 	 update_CRC(info->tc_sbgr_select, 1, crc);	 update_CRC(info->dyn_cross_on, 1, crc);	 update_CRC(info->mc_prediction_on, 1, crc);	 if (info->tc_sbgr_select == 1)	    update_CRC (info->tc_allocation, fr_ps->alloc_bits, crc);	 else	    for (i = 0; i < 12; i++)	       update_CRC (info->tc_alloc[i], fr_ps->alloc_bits, crc);	   	 if (info->dyn_cross_on == 1)	 {		update_CRC(info->dyn_cross_LR, 1, crc);		for(i = 0; i < 12; i++)		{			update_CRC(info->dyn_cross_mode[i], fr_ps->dyn_cross_bits, crc);			if (info->surround == 3)				update_CRC(info->dyn_second_stereo[i], 1, crc);		}	 }	 if (info->mc_prediction_on == 1)	 {		for(i = 0; i < 8; i++)		{ 	/* new sbgr < 8 */			update_CRC(info->mc_prediction[i], 1, crc);			if( info->mc_prediction[i] == 1 )			{			   for(pci=0; pci< pred_coef_table[fr_ps->pred_mode][info->dyn_cross_mode[i]]; pci++)				update_CRC(info->mc_predsi[i][pci], 2, crc);			}		}	 }	 if( info->lfe )		update_CRC(info->lfe_alloc, (*alloc)[0][0].bits, crc);	 for (i=0;i<sblimit;i++)		   if( info->dyn_cross_on == 0)			for(m = ch_start; m < channels; ++m)			{				if((i < 12) || (m != 2) || (fr_ps->header->center != 3))					update_CRC(bit_alloc[m][i], (*alloc)[i][0].bits, crc);					/* to limit the CRC calc., if the phant. center valid */			}		   else		   {			if(i == 0) sbgr = 0;			else	   		   for(c = 1; c < 12; c++)	   		   {	      			if((sb_groups[c-1] < i) && (i <= sb_groups[c]))	      			{			  	   sbgr = c;  /* search the valid subband group */			  	   break;	         		}			   }			/* 960816 FdB new setup for dyn. crosstalk modes */			if (info->dyn_cross_mode[sbgr] == 0)			{			   for (m = ch_start; m < channels; m++)			      if ((info->center != 3) || (i < 12) || (m !=2))				 if (info->surround == 3 && info->dyn_second_stereo[sbgr] == 1)				 {				    if ((info->center == 0 || m != 4) && (info->center != 0 || m != (ch_start+1)))				       update_CRC (bit_alloc[m][i], (*alloc)[i][0].bits, crc);				 }				 else				    update_CRC (bit_alloc[m][i], (*alloc)[i][0].bits, crc);			}			else if (fr_ps->dyn_cross_bits == 1)   /* for channel mode 3/0 and 2/1 */			{			   if (info->surround == 3)		/* 3/0 + 2/0 */			   {			      update_CRC (bit_alloc[3][i], (*alloc)[i][0].bits, crc);			      if (info->dyn_second_stereo[sbgr] == 0)			         update_CRC (bit_alloc[4][i], (*alloc)[i][0].bits, crc);			   }			}			else if (fr_ps->dyn_cross_bits == 3)   /* for channel mode 3/1 and 2/2 */			{			   if ((info->center != 3) || (i < 12))    /* 3/2 + no phantom center */			      if ((info->dyn_cross_mode[sbgr] == 1) || (info->dyn_cross_mode[sbgr] == 4))			         update_CRC (bit_alloc[2][i], (*alloc)[i][0].bits, crc);			   if (info->dyn_cross_mode[sbgr] == 2)			      update_CRC (bit_alloc[3][i], (*alloc)[i][0].bits, crc);			} 			else if (fr_ps->dyn_cross_bits == 4)   /* for channel mode 3/2 */			{			   /* T2 */			   if ((info->center != 3) || (i < 12))    /* 3/2 + no phantom center */			      switch (info->dyn_cross_mode[sbgr])			   {			   case 1 :   /* T2 contains bitalloc info */			   case 2 :			   case 4 :			   case 8 :			   case 9 :			   case 10: 			   case 11: 			   case 12: 			   case 14: 				      update_CRC (bit_alloc[2][i], (*alloc)[i][0].bits, crc);				      break;			   }			   /* T3 */			   switch (info->dyn_cross_mode[sbgr])			   {			   case 1 :   /* T3 contains bitalloc info */			   case 3 :			   case 5 :			   case 8 :			   case 10: 			   case 13: 				      update_CRC (bit_alloc[3][i], (*alloc)[i][0].bits, crc);				      break;			   }			   /* T4 */			   switch (info->dyn_cross_mode[sbgr])			   {			   case 2 :   /* T4 contains bitalloc info */			   case 3 :			   case 6 :			   case 9 : 				      update_CRC (bit_alloc[4][i], (*alloc)[i][0].bits, crc);				      break;			   }			}		   }	     for (i = 0; i < sblimit; i++)		for (m = ch_start; m < channels; m++)			if (bit_alloc[m][i])				update_CRC (scfsi[m][i], 2, crc); }#ifdef Augmentation_7chvoid mc_aug_error_check(frame_params *fr_ps,		    unsigned int bit_alloc[7][SBLIMIT], 		    unsigned int scfsi[7][SBLIMIT],		    unsigned int *crc){   int i, m, l, pci,c,sbgr;   layer *info = fr_ps->header;   int sblimit = fr_ps->sblimit_mc;   al_table *alloc = fr_ps->alloc_mc;   *crc = 0xffff; /* changed from '0' 92-08-11 shn */   update_CRC(info->aug_mtx_proc, 2, crc);   update_CRC(info->aug_dyn_cross_on, 1, crc);   update_CRC(info->aug_future_ext, 1, crc);   if(info->aug_mtx_proc == 0)      for(i = 0; i < 12; i++)	 update_CRC(info->tc_aug_alloc[i], 3, crc);   else if(info->aug_mtx_proc == 1)      for(i = 0; i < 12; i++)	 update_CRC(info->tc_aug_alloc[i], 2, crc);        if(info->aug_dyn_cross_on == 1)      for(i = 0; i < 12; i++)	 update_CRC(info->dyn_cross_aug_mode[i], 5, crc);   for (i=0;i<sblimit;i++)   {      if(i == 0) sbgr = 0;      else	 for(c = 1; c < 12; c++)	 {	    if((sb_groups[c-1] < i) && (i <= sb_groups[c]))	    {	      sbgr = c;  /* search the valid subband group */	      break;	    }	 }       /* check bitalloc info */      switch (info->dyn_cross_aug_mode[sbgr])      {      case  0: /* T5 and T6 contains bitalloc info */	       update_CRC(bit_alloc[5][i], (*alloc)[i][0].bits, crc);	       update_CRC(bit_alloc[6][i], (*alloc)[i][0].bits, crc);	       break;      case  1: /* T5 contains bitalloc info */      case  2:      case  3:      case  4:	       update_CRC(bit_alloc[5][i], (*alloc)[i][0].bits, crc);	       break;      case  5:   /* T6 contains bitalloc info */      case 10:      case 14:	       update_CRC(bit_alloc[6][i], (*alloc)[i][0].bits, crc);	       break;      }   }   for (i = 0; i < sblimit; i++)      for (m = 5; m < 7; m++)	 if (bit_alloc[m][i])		 update_CRC (scfsi[m][i], 2, crc); }#endifint mc_ext_error_check (frame_params *fr_ps, int bytes, int bits){	layer *info = fr_ps->header;	int i;	unsigned int crc;	crc = 0xffff;	update_CRC(info->ext_length, 11, &crc);	update_CRC(info->reserved_bit, 1, &crc);	for( i = 0; i < bytes; i++)		update_CRC(info->ext_crc_bits[i], 8, &crc);	update_CRC(info->ext_crc_bits[bytes], bits, &crc);	if (crc != info->ext_crc_check)	{		printf ("\nERROR in EXT.-CRC \n");		return (0);	}	else		return(1);}/*******************************************************************************  End of CRC error protection package******************************************************************************/#ifdef  MACINTOSH/*******************************************************************************  Set Macintosh file attributes.******************************************************************************/void    set_mac_file_attr(char fileName[MAX_NAME_SIZE],			  short vRefNum,			  OsType creator,			  OsType fileType){short   theFile;char    pascal_fileName[MAX_NAME_SIZE];FInfo   fndrInfo;		CtoPstr(strcpy(pascal_fileName, fileName));        FSOpen(pascal_fileName, vRefNum, &theFile);        GetFInfo(pascal_fileName, vRefNum, &fndrInfo);		fndrInfo.fdCreator = creator;        fndrInfo.fdType = fileType;        SetFInfo(pascal_fileName, vRefNum, &fndrInfo);        FSClose(theFile);}#endif