common.c

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/**********************************************************************
 * ISO MPEG Audio Subgroup Software Simulation Group (1996)
 * ISO 13818-3 MPEG-2 Audio Multichannel Decoder
 *
 * $Id: common.c 1.12 1997/01/17 04:25:12 rowlands Exp $
 *
 * $Log: common.c $
 * Revision 1.12  1997/01/17 04:25:12  rowlands
 * Fixed base bitstream joint stereo bugs.
 *
 * Removed incorrect dependence on jsbound in the calculation of the
 * mc crc.
 *
 * Revision 1.11  1996/06/18 22:47:29  rowlands
 * Added extra debug output
 *
 * Revision 1.10  1996/04/18 05:37:23  rowlands
 * Release following Florence meeting
 *
 * Revision 1.9  1996/02/12 07:13:06  rowlands
 * Release following Munich meeting
 *
 * Revision 1.8.1.1  1996/01/20  17:28:45  rowlands
 * Received from Ralf Schwalbe (Telekom FTZ) - includes prediction
 *
 * Revision 1.6.1.3  1995/08/14  08:10:19  tenkate
 * ML-LSF added Warner ten Kate 7/8/95 (Philips)
 * "alloc_4" table copied from LSF-directory.
 * SmpFrqIndex() extended.
 *
 * Revision 1.6.1.1  1995/07/14  06:12:46  rowlands
 * Updated dynamic crosstalk from FTZ: revision FTZ_03
 *
 * Revision 1.6  1995/06/22  01:23:00  rowlands
 * Merged FTZ dynamic crosstalk
 *
 * Revision 1.3.3.1  1995/06/16  08:40:12  rowlands
 * Input from Sang Wook Kim (Samsung AIT)
 *
 **********************************************************************/

/**********************************************************************
 *   date   programmers                comment                        *
 * 2/25/91  Douglas Wong        start of version 1.0 records          *
 * 3/06/91  Douglas Wong        rename setup.h to dedef.h             *
 *                              removed extraneous variables          *
 *                              removed window_samples (now part of   *
 *                              filter_samples)                       *
 * 3/07/91  Davis Pan           changed output file to "codmusic"     *
 * 5/10/91  Vish (PRISM)        Ported to Macintosh and Unix.         *
 *                              Incorporated new "out_fifo()" which   *
 *                              writes out last incomplete buffer.    *
 *                              Incorporated all AIFF routines which  *
 *                              are also compatible with SUN.         *
 *                              Incorporated user interface for       *
 *                              specifying sound file names.          *
 *                              Also incorporated user interface for  *
 *                              writing AIFF compatible sound files.  *
 * 27jun91  dpwe (Aware)        Added musicout and &sample_frames as  *
 *                              args to out_fifo (were glob refs).    *
 *                              Used new 'frame_params' struct.       *
 *                              Clean,simplify, track clipped output  *
 *                              and total bits/frame received.        *
 * 7/10/91  Earle Jennings      changed to floats to FLOAT            *
 *10/ 1/91  S.I. Sudharsanan,   Ported to IBM AIX platform.           *
 *          Don H. Lee,                                               *
 *          Peter W. Farrett                                          *
 *10/ 3/91  Don H. Lee          implemented CRC-16 error protection   *
 *                              newly introduced functions are        *
 *                              buffer_CRC and recover_CRC_error      *
 *                              Additions and revisions are marked    *
 *                              with "dhl" for clarity                *
 * 2/11/92  W. Joseph Carter    Ported new code to Macintosh.  Most   *
 *                              important fixes involved changing     *
 *                              16-bit ints to long or unsigned in    *
 *                              bit alloc routines for quant of 65535 *
 *                              and passing proper function args.     *
 *                              Removed "Other Joint Stereo" option   *
 *                              and made bitrate be total channel     *
 *                              bitrate, irrespective of the mode.    *
 *                              Fixed many small bugs & reorganized.  *
 **********************************************************************
 *                                                                    *
 *                                                                    *
 *  MPEG/audio Phase 2 coding/decoding multichannel                   *
 *                                                                    *
 *  Version 1.0                                                       *
 *                                                                    *
 *  7/27/93        Susanne Ritscher,  IRT Munich                      *
 *                                                                    *
 *                  thanks to                                         *
 *                  Ralf Schwalbe,    Telekom FTZ Berlin              *
 *                  Heiko Purnhagen,  Uni Hannover                    *
 *                                                                    *
 *  Version 2.0                                                       *
 *                                                                    *
 *  8/27/93        Susanne Ritscher, IRT Munich                       *
 *                 Channel-Switching is working                       *
 *                                                                    *
 *  Version 2.1                                                       *
 *                                                                    *
 *  9/1/93         Susanne Ritscher,  IRT Munich                      *
 *                 all channels normalized                            *
 *                                                                    *
 *  Version 3.0                                                       *
 *                                                                    *
 *  06/16/94       Ralf Schwalbe, Telekom FTZ Berlin                  *
 *                 all sources and variables adapted due to MPEG-2 -  *
 *                 DIS from March 1994                                *
 *                  - dematrix and denormalize procedure              *
 *                  - new tc - allocation (0-7)                       *
 *                  - some new structures and variables as a basis    *
 *                    for further decoding modes                      *
 **********************************************************************
 *								      *
 *  Version 1.0                                                       *
 *                                                                    *
 *  11/04/94       Ralf Schwalbe,  Telekom FTZ Berlin                 *
 *                  - decoding tc-allocation                          *
 *                  - some new subroutines, globale variables and     *
 *                    structures (important to handle the ext. bitst.)*
 *                  - changed all functions to ANSI-C funktion header *
 *		    - corrected some bugs to decode bitstreams > 512kB*
 *								      *
 *  Version 1.1                                                       *
 *                                                                    *
 *  12/07/94       Ralf Schwalbe,  Telekom FTZ Berlin                 *
 *                  - decoding extension bitstream                    *
 *                                                                    *
 *  Version 1.1.1                                                     *
 *                 Ralf Schwalbe, Telekom FTZ Berlin                  *
 *                  - fixed some bugs                                 *
 *                                                                    *
 *  Version 1.2                                                       *
 *                                                                    *
 *  6/21/95       Ralf Schwalbe, Deutsche Telekom FTZ Berlin          *
 *            	    - decoding dynamic crosstalk                      *
 *                  - decoding phantom center                         * 
 *                  - decoding MPEG1 compatible part only (stereo)    *
 *                  - corrected some settings and bugs                *
 *                                                                    *  
 *  7/12/95	  Ralf Schwalbe, Deutsche Telekom FTZ Berlin          *
 *		    - corrected dynamic crosstalk 		      *
 *		    - 3/2,3/1,3/0,2/1, channel configurations         *
 *                    are working                                     *
 *		  						      *
 * 10/31/95	  Ralf Schwalbe, Deutsche Telekom FTZ Berlin	      *
 *		    - decoding of LFE-channel is working  	      *
 *		    - corrected any settings and bugs		      *
 *		    - corrected table-switch for channel mode < 3/2   *
 *		      and tc-allocation / dyn-crosstalk		      *
 *		    - still a problem with compl. bitstream 18/19     *
 *								      *	
 * 01/12/96	  Ralf Schwalbe, Deutsche Telekom TZ Darmstadt	      *
 *		    - decoder prediction installed		      *
 *		    - problem with compl. bitstream 19 solved,        *
 *								      *  
 *  Version 2.0                                                       *
 *                                                                    *
 * 01/28/97       Frans de Bont, Philips Sound & Vision, Eindhoven    *
 *		    - simultaneous use of tc allocation and dynamic   *
 *		      crosstalk working for all configurations	      *
 *		    - prediction working for all configurations	      *
 *		    - layer 1 MC working			      *
 *		    - variable bit rate and extension bitstreams      *
 *		    - fully compliant to 13818-3.2                    *
 *                                                                    *				      *		    
 **********************************************************************/

/**********************************************************************
 *                                                                    *
 *  06/06/95       Sang Wook Kim,  Samsung AIT                        *
 *                 Bug corrected in pick_table                        *
 *								      *
 **********************************************************************/

/***********************************************************************
*
*  Global Include Files
*
***********************************************************************/

#include        "common.h"
#include        "decoder.h" /* 23/03/1995 JMZ Test_bit_stream */

#ifdef  MACINTOSH

#include        <SANE.h>
#include        <pascal.h>

#endif

#include <string.h>
#include <ctype.h>

/***********************************************************************
*
*  Global Variable Definitions
*
***********************************************************************/
char *mode_names[4] = { "stereo", "j-stereo", "dual-ch", "single-ch" };
char *layer_names[3] = { "I", "II", "III" };

double  s_freq[4] = {44.1, 48, 32, 0};

int	  bitrate[3][15] = {
			 {1000,32,64,96,128,160,192,224,256,288,320,352,384,416,448},
			 {1000,32,48,56,64,80,96,112,128,160,192,224,256,320,384},
			 {1000,32,40,48,56,64,80,96,112,128,160,192,224,256,320}
        };

double multiple[64] = {
2.00000000000000, 1.58740105196820, 1.25992104989487,
1.00000000000000, 0.79370052598410, 0.62996052494744, 0.50000000000000,
0.39685026299205, 0.31498026247372, 0.25000000000000, 0.19842513149602,
0.15749013123686, 0.12500000000000, 0.09921256574801, 0.07874506561843,
0.06250000000000, 0.04960628287401, 0.03937253280921, 0.03125000000000,
0.02480314143700, 0.01968626640461, 0.01562500000000, 0.01240157071850,
0.00984313320230, 0.00781250000000, 0.00620078535925, 0.00492156660115,
0.00390625000000, 0.00310039267963, 0.00246078330058, 0.00195312500000,
0.00155019633981, 0.00123039165029, 0.00097656250000, 0.00077509816991,
0.00061519582514, 0.00048828125000, 0.00038754908495, 0.00030759791257,
0.00024414062500, 0.00019377454248, 0.00015379895629, 0.00012207031250,
0.00009688727124, 0.00007689947814, 0.00006103515625, 0.00004844363562,
0.00003844973907, 0.00003051757813, 0.00002422181781, 0.00001922486954,
0.00001525878906, 0.00001211090890, 0.00000961243477, 0.00000762939453,
0.00000605545445, 0.00000480621738, 0.00000381469727, 0.00000302772723,
0.00000240310869, 0.00000190734863, 0.00000151386361, 0.00000120155435,
1E-20
};

int sb_groups[12] = { 0, 1, 2, 3, 4, 5, 6, 7, 9, 11, 15, 26};

/*int transmission_channel[8][5] = {{0, 1, 2, 3, 4},
				    {0, 1, 5, 3, 4},
				    {0, 1, 6, 3, 4},
				    {0, 1, 2, 5, 4},
				    {0, 1, 2, 3, 6},
				    {0, 1, 2, 5, 6},
				    {0, 1, 6, 5, 4},
				    {0, 1, 5, 3, 6}};
*/


/***********************************************************************
*
*  Global Function Definitions
*
***********************************************************************/

/* The system uses a variety of data files.  By opening them via this
   function, we can accommodate various locations. */

FILE *OpenTableFile(char *name)
{
char fulname[80];
char *envdir;
FILE *f;

	 fulname[0] = '\0';

#ifdef TABLES_PATH
	   strcpy(fulname, TABLES_PATH);   /* default relative path for tables */
#endif /* TABLES_PATH */          /* (includes terminal path seperator */

#ifdef UNIX                       /* envir. variables for UNIX only */
	   {
		char *getenv(const char *);

        envdir = getenv(MPEGTABENV);   /* check for environment */
        if(envdir != NULL)
            strcpy(fulname, envdir);
        strcat(fulname, PATH_SEPARATOR);  /* add a "/" on the end */
      }
#endif /* UNIX */

	strcat(fulname, name);
    if( (f=fopen(fulname,"r"))==NULL ) {
        fprintf(stderr,"OpenTable: could not find %s\n", fulname);

#ifdef UNIX
          if(envdir != NULL)
			fprintf(stderr,"Check %s directory '%s'\n",MPEGTABENV, envdir);
          else
            fprintf(stderr,"Check local directory './%s' or setenv %s\n",
                    TABLES_PATH, MPEGTABENV);
#else /* not unix : no environment variables */

#ifdef TABLES_PATH
            fprintf(stderr,"Check local directory './%s'\n",TABLES_PATH);
#endif /* TABLES_PATH */

#endif /* UNIX */

    }
    return f;
}

/***********************************************************************
/*
/* Read one of the data files ("alloc_*") specifying the bit allocation/
/* quatization parameters for each subband in layer II encoding
/*
/**********************************************************************/
/* read in table, return # subbands */
int read_bit_alloc(int table, al_table *alloc)  

{
        long a, b, c, d, i, j;
		FILE *fp;
        char name[16], t[80];
        int sblim;

        strcpy(name, "alloc_0");

		switch (table) {
                case 0 : name[6] = '0';         break;
                case 1 : name[6] = '1';         break;
                case 2 : name[6] = '2';         break;
                case 3 : name[6] = '3';         break;
                case 4 : name[6] = '4';         break; /* for MultiLingual-LSF , WtK 7/8/95 */
                default : name[6] = '0';
		}

        if (!(fp = OpenTableFile(name))) {
                fprintf (stderr, "Please check bit allocation table %s\n", name);
                exit (1);
        }

#ifdef	PrintBitDebug
	printf("using bit allocation table %s\n", name);
#endif

        fgets(t, 80, fp);
        sscanf(t, "%d\n", &sblim);
        while (!feof(fp)) {
				fgets(t, 80, fp);
                sscanf(t, "%ld %ld %ld %ld %ld %ld\n", &i, &j, &a, &b, &c, &d);
						(*alloc)[i][j].steps = a;
                        (*alloc)[i][j].bits  = b;
                        (*alloc)[i][j].group = c;
                        (*alloc)[i][j].quant = d;
        }
        fclose(fp);
		return sblim;
}

/***********************************************************************
/*
/* Using the decoded info the appropriate possible quantization per
/* subband table is loaded
/*
/**********************************************************************/
/* choose table, load if necess, return # sb's */
int pick_table (frame_params *fr_ps)   
{
   int table, tableml, lay, ws, bsp, br_per_ch, sfrq;
   int sblim = fr_ps->sblimit;     /* return current value if no load */

   lay = fr_ps->header->lay - 1;
   bsp = fr_ps->header->bitrate_index;

   /* BUG corrected SWKim060695 */
   br_per_ch = bitrate[lay][bsp] / (fr_ps->stereo /* + fr_ps->mc_channel*/);
   ws = fr_ps->header->sampling_frequency;
   sfrq = s_freq[ws];

   /* decision rules refer to per-channel bitrates (kbits/sec/chan) */
   if ((sfrq == 48 && br_per_ch >= 56) ||
       (br_per_ch >= 56 && br_per_ch <= 80)) table = 0;
   else if (sfrq != 48 && br_per_ch >= 96) table = 1;
   else if (sfrq != 32 && br_per_ch <= 48) table = 2;
   else table = 3;
   if (fr_ps->tab_num != table)
   {
      if (fr_ps->tab_num >= 0)
        mem_free ((void **) &(fr_ps->alloc));
      fr_ps->alloc = (al_table *) mem_alloc (sizeof(al_table), "alloc");
      sblim = read_bit_alloc (fr_ps->tab_num = table, fr_ps->alloc);
   }
   return sblim;
}


/* choose MC and ML tables, load if necess, return # sb's */
void mc_pick_table (frame_params *fr_ps)   
{
   int tablemc, tableml, ws, sfrq;

   /* BUG corrected SWKim060695 */
   ws = fr_ps->header->sampling_frequency;
   sfrq = s_freq[ws];

   /* decision rules refer to sampling frequency */
   if (sfrq == 48)
      tablemc = 0;
   else
      tablemc = 1;

   if (fr_ps->tab_num_mc != tablemc)
   {
      if (fr_ps->tab_num >= 0)
	 mem_free ((void **)& (fr_ps->alloc_mc));
      fr_ps->alloc_mc = (al_table *) mem_alloc (sizeof(al_table), "alloc_mc");
      fr_ps->sblimit_mc = read_bit_alloc (fr_ps->tab_num_mc = tablemc, fr_ps->alloc_mc);
   }

   if (fr_ps->header->no_of_multi_lingual_ch > 0)
   {
      /* LSF MultiLingual 7/8/95 WtK */
      if (fr_ps->header->multi_lingual_fs == 0)
      {
	 fr_ps->tab_num_ml = fr_ps->tab_num_mc;
	 fr_ps->alloc_ml   = fr_ps->alloc_mc;
	 fr_ps->sblimit_ml = fr_ps->sblimit_mc;
      }
      else
      {
	 tableml = 4;
	 if (fr_ps->tab_num_ml != tableml)
	 {
	    if (fr_ps->tab_num_ml >= 0)
	       mem_free ((void **)&(fr_ps->alloc_ml));
	    fr_ps->alloc_ml = (al_table *) mem_alloc (sizeof(al_table), "alloc_ml");
	    fr_ps->sblimit_ml = read_bit_alloc (fr_ps->tab_num_ml = tableml, fr_ps->alloc_ml);
	 }
      } /* ml_fs==0 */
   } /* ml_ch>0 */
}


int js_bound(int lay, int m_ext)
{
static int jsb_table[3][4] =  { { 4, 8, 12, 16 }, { 4, 8, 12, 16},
								{ 0, 4, 8, 16} };  /* lay+m_e -> jsbound */

    if(lay<1 || lay >3 || m_ext<0 || m_ext>3) {
        fprintf (stderr, "js_bound bad layer/modext (%d/%d)\n", lay, m_ext);
        exit (1);
    }
    return(jsb_table[lay-1][m_ext]);
}

/* interpret data in hdr str to fields in fr_ps */
void hdr_to_frps (frame_params *fr_ps)
{
	layer *hdr = fr_ps->header;     /* (or pass in as arg?) */

	fr_ps->actual_mode = hdr->mode;
	if (hdr->mode != MPG_MD_NONE)
		fr_ps->stereo = (hdr->mode == MPG_MD_MONO) ? 1 : 2;
	else
		fr_ps->stereo = 0;

	Bitrate = bitrate[hdr->lay-1][hdr->bitrate_index];
	S_freq = s_freq[hdr->sampling_frequency];
	
	if (hdr->lay == 2)