l3psy.c

ISO mp3 sources (distribution 10) Layer 1/2/3, C Source, 512 k Sources of the Mpeg 1,2 layer 1,2

/**********************************************************************
 * ISO MPEG Audio Subgroup Software Simulation Group (1996)
 * ISO 13818-3 MPEG-2 Audio Encoder - Lower Sampling Frequency Extension
 *
 * $Id: l3psy.c,v 1.2 1997/01/19 22:28:29 rowlands Exp $
 *
 * $Log: l3psy.c,v $
 * Revision 1.2  1997/01/19 22:28:29  rowlands
 * Layer 3 bug fixes from Seymour Shlien
 *
 * Revision 1.1  1996/02/14 04:04:23  rowlands
 * Initial revision
 *
 * Received from Mike Coleman
 **********************************************************************/
/**********************************************************************
 *   date   programmers         comment                               *
 * 2/25/91  Davis Pan           start of version 1.0 records          *
 * 5/10/91  W. Joseph Carter    Ported to Macintosh and Unix.         *
 * 7/10/91  Earle Jennings      Ported to MsDos.                      *
 *                              replace of floats with FLOAT          *
 * 2/11/92  W. Joseph Carter    Fixed mem_alloc() arg for "absthr".   *
 * 3/16/92  Masahiro Iwadare	Modification for Layer III            *
 * 17/4/93  Masahiro Iwadare    Updated for IS Modification           *
 **********************************************************************/

#include "common.h"
#include "encoder.h"
#include "l3psy.h"
#include "l3side.h"
#include <assert.h>

#define maximum(x,y) ( (x>y) ? x : y )
#define minimum(x,y) ( (x<y) ? x : y )

void L3para_read( double sfreq, int numlines[CBANDS], int partition_l[HBLKSIZE],
		  double minval[CBANDS], double qthr_l[CBANDS], double norm_l[CBANDS],
		  double s3_l[CBANDS][CBANDS], int partition_s[HBLKSIZE_s], double qthr_s[CBANDS_s],
		  double norm_s[CBANDS_s], double SNR_s[CBANDS_s],
		  int cbw_l[SBMAX_l], int bu_l[SBMAX_l], int bo_l[SBMAX_l],
		  double w1_l[SBMAX_l], double w2_l[SBMAX_l],
		  int cbw_s[SBMAX_s], int bu_s[SBMAX_s], int bo_s[SBMAX_s],
		  double w1_s[SBMAX_s], double w2_s[SBMAX_s] );
									
void L3psycho_anal( short int *buffer, short int savebuf[1344], int chn, int lay, FLOAT snr32[32],
		    double sfreq, double ratio_d[21], double ratio_ds[12][3],
		    double *pe, gr_info *cod_info )
{
    static double ratio[2][21];
    static double ratio_s[2][12][3];
    int blocktype;
    unsigned int   b, i, j, k;
    double         r_prime, phi_prime; /* not FLOAT */
    FLOAT          freq_mult, bval_lo, min_thres, sum_energy;
    double         tb, temp1,temp2,temp3;

    /*         nint(); Layer III */
    double   thr[CBANDS];

/* The static variables "r", "phi_sav", "new", "old" and "oldest" have    */
/* to be remembered for the unpredictability measure.  For "r" and        */
/* "phi_sav", the first index from the left is the channel select and     */
/* the second index is the "age" of the data.                             */


   static FLOAT window_s[BLKSIZE_s] ;
 static int     new = 0, old = 1, oldest = 0;
 static int     init = 0, flush, sync_flush, syncsize, sfreq_idx;
 static double 	cw[HBLKSIZE], eb[CBANDS];
 static double 	ctb[CBANDS];
 static double	SNR_l[CBANDS], SNR_s[CBANDS_s];
 static int	init_L3;
 static double	minval[CBANDS],qthr_l[CBANDS],norm_l[CBANDS];
 static double	qthr_s[CBANDS_s],norm_s[CBANDS_s];
 static double	nb_1[2][CBANDS], nb_2[2][CBANDS];
 static double	s3_l[CBANDS][CBANDS]; /* s3_s[CBANDS_s][CBANDS_s]; */

/* Scale Factor Bands */
 static int	cbw_l[SBMAX_l],bu_l[SBMAX_l],bo_l[SBMAX_l] ;
 static int	cbw_s[SBMAX_s],bu_s[SBMAX_s],bo_s[SBMAX_s] ;
 static double	w1_l[SBMAX_l], w2_l[SBMAX_l];
 static double	w1_s[SBMAX_s], w2_s[SBMAX_s];
 static double	en[SBMAX_l],   thm[SBMAX_l] ;
 static int	blocktype_old[2] ;
 int	sb,sblock;
 static int	partition_l[HBLKSIZE],partition_s[HBLKSIZE_s];


/* The following static variables are constants.                           */

 static double  nmt = 5.5;

 static FLOAT   crit_band[27] = {0,  100,  200, 300, 400, 510, 630,  770,
                               920, 1080, 1270,1480,1720,2000,2320, 2700,
                              3150, 3700, 4400,5300,6400,7700,9500,12000,
                             15500,25000,30000};

 static FLOAT   bmax[27] = {20.0, 20.0, 20.0, 20.0, 20.0, 17.0, 15.0,
                            10.0,  7.0,  4.4,  4.5,  4.5,  4.5,  4.5,
                             4.5,  4.5,  4.5,  4.5,  4.5,  4.5,  4.5,
                             4.5,  4.5,  4.5,  3.5,  3.5,  3.5};

/* The following pointer variables point to large areas of memory         */
/* dynamically allocated by the mem_alloc() function.  Dynamic memory     */
/* allocation is used in order to avoid stack frame or data area          */
/* overflow errors that otherwise would have occurred at compile time     */
/* on the Macintosh computer.                                             */

 FLOAT          *grouped_c, *grouped_e, *nb, *cb, *ecb, *bc;
 FLOAT          *wsamp_r, *wsamp_i, *phi, *energy;
 static FLOAT	energy_s[3][256];
 static FLOAT phi_s[3][256] ; /* 256 samples not 129 */
 FLOAT          *c, *fthr;
 F32            *snrtmp;

 static	int	*numlines ;
 static int     *partition;
 static FLOAT   *cbval, *rnorm;
 static FLOAT   *window;
 static FLOAT   *absthr;
 static double  *tmn;
 static FCB     *s;
 static FHBLK   *lthr;
 static F2HBLK  *r, *phi_sav;

/* These dynamic memory allocations simulate "automatic" variables        */
/* placed on the stack.  For each mem_alloc() call here, there must be    */
/* a corresponding mem_free() call at the end of this function.           */

 grouped_c = (FLOAT *) mem_alloc(sizeof(FCB), "grouped_c");
 grouped_e = (FLOAT *) mem_alloc(sizeof(FCB), "grouped_e");
 nb = (FLOAT *) mem_alloc(sizeof(FCB), "nb");
 cb = (FLOAT *) mem_alloc(sizeof(FCB), "cb");
 ecb = (FLOAT *) mem_alloc(sizeof(FCB), "ecb");
 bc = (FLOAT *) mem_alloc(sizeof(FCB), "bc");
 wsamp_r = (FLOAT *) mem_alloc(sizeof(FBLK), "wsamp_r");
 wsamp_i = (FLOAT *) mem_alloc(sizeof(FBLK), "wsamp_i");
 phi = (FLOAT *) mem_alloc(sizeof(FBLK), "phi");
 energy = (FLOAT *) mem_alloc(sizeof(FBLK), "energy");
 c = (FLOAT *) mem_alloc(sizeof(FHBLK), "c");
 fthr = (FLOAT *) mem_alloc(sizeof(FHBLK), "fthr");
 snrtmp = (F32 *) mem_alloc(sizeof(F2_32), "snrtmp");

    assert( lay == 3 );
 if(init==0){

/* These dynamic memory allocations simulate "static" variables placed    */
/* in the data space.  Each mem_alloc() call here occurs only once at     */
/* initialization time.  The mem_free() function must not be called.      */
     numlines = (int *) mem_alloc(sizeof(ICB), "numlines");
     partition = (int *) mem_alloc(sizeof(IHBLK), "partition");
     cbval = (FLOAT *) mem_alloc(sizeof(FCB), "cbval");
     rnorm = (FLOAT *) mem_alloc(sizeof(FCB), "rnorm");
     window = (FLOAT *) mem_alloc(sizeof(FBLK), "window");
     absthr = (FLOAT *) mem_alloc(sizeof(FHBLK), "absthr"); 
     tmn = (double *) mem_alloc(sizeof(DCB), "tmn");
     s = (FCB *) mem_alloc(sizeof(FCBCB), "s");
     lthr = (FHBLK *) mem_alloc(sizeof(F2HBLK), "lthr");
     r = (F2HBLK *) mem_alloc(sizeof(F22HBLK), "r");
     phi_sav = (F2HBLK *) mem_alloc(sizeof(F22HBLK), "phi_sav");

/*#if 0 */
     i = sfreq + 0.5;
     switch(i){
        case 32000: sfreq_idx = 0; break;
        case 44100: sfreq_idx = 1; break;
        case 48000: sfreq_idx = 2; break;
        default:    printf("error, invalid sampling frequency: %d Hz\n",i);
        exit(-1);
     }
     printf("absthr[][] sampling frequency index: %d\n",sfreq_idx);
     read_absthr(absthr, sfreq_idx);
     switch(lay){
	case 1: sync_flush=576; flush=384; syncsize=1024; break;
	case 2: sync_flush=480; flush=576; syncsize=1056; break;
	case 3: sync_flush=768; flush=576; syncsize=1344; break;
       default: printf("Bad lay value:(%d)",lay); exit(-1); break;
     }
/* #endif */

/* calculate HANN window coefficients */
/*   for(i=0;i<BLKSIZE;i++)  window[i]  =0.5*(1-cos(2.0*PI*i/(BLKSIZE-1.0)));*/
     for(i=0;i<BLKSIZE;i++)  window[i]  =0.5*(1-cos(2.0*PI*(i-0.5)/BLKSIZE));
     for(i=0;i<BLKSIZE_s;i++)window_s[i]=0.5*(1-cos(2.0*PI*(i-0.5)/BLKSIZE_s));
/* reset states used in unpredictability measure */
     for(i=0;i<HBLKSIZE;i++){
        r[0][0][i]=r[1][0][i]=r[0][1][i]=r[1][1][i]=0;
        phi_sav[0][0][i]=phi_sav[1][0][i]=0;
        phi_sav[0][1][i]=phi_sav[1][1][i]=0;
        lthr[0][i] = 60802371420160.0;
        lthr[1][i] = 60802371420160.0;
     }
/*****************************************************************************
 * Initialization: Compute the following constants for use later             *
 *    partition[HBLKSIZE] = the partition number associated with each        *
 *                          frequency line                                   *
 *    cbval[CBANDS]       = the center (average) bark value of each          *
 *                          partition                                        *
 *    numlines[CBANDS]    = the number of frequency lines in each partition  *
 *    tmn[CBANDS]         = tone masking noise                               *
 *****************************************************************************/
/* compute fft frequency multiplicand */
     freq_mult = sfreq/BLKSIZE;
 
/* calculate fft frequency, then bval of each line (use fthr[] as tmp storage)*/
     for(i=0;i<HBLKSIZE;i++){
        temp1 = i*freq_mult;
        j = 1;
        while(temp1>crit_band[j])j++;
        fthr[i]=j-1+(temp1-crit_band[j-1])/(crit_band[j]-crit_band[j-1]);
     }
     partition[0] = 0;
/* temp2 is the counter of the number of frequency lines in each partition */
     temp2 = 1;
     cbval[0]=fthr[0];
     bval_lo=fthr[0];
     for(i=1;i<HBLKSIZE;i++){
        if((fthr[i]-bval_lo)>0.33){
           partition[i]=partition[i-1]+1;
           cbval[partition[i-1]] = cbval[partition[i-1]]/temp2;
           cbval[partition[i]] = fthr[i];
           bval_lo = fthr[i];
           numlines[partition[i-1]] = temp2;
           temp2 = 1;
        }
        else {
           partition[i]=partition[i-1];
           cbval[partition[i]] += fthr[i];
           temp2++;
        }
     }
     numlines[partition[i-1]] = temp2;
     cbval[partition[i-1]] = cbval[partition[i-1]]/temp2;
 
/************************************************************************
 * Now compute the spreading function, s[j][i], the value of the spread-*
 * ing function, centered at band j, for band i, store for later use    *
 ************************************************************************/
     for(j=0;j<CBANDS;j++){
        for(i=0;i<CBANDS;i++){
           temp1 = (cbval[i] - cbval[j])*1.05;
           if(temp1>=0.5 && temp1<=2.5){
              temp2 = temp1 - 0.5;
              temp2 = 8.0 * (temp2*temp2 - 2.0 * temp2);
           }
           else temp2 = 0;
           temp1 += 0.474;
           temp3 = 15.811389+7.5*temp1-17.5*sqrt((double) (1.0+temp1*temp1));
           if(temp3 <= -100) s[i][j] = 0;
           else {
              temp3 = (temp2 + temp3)*LN_TO_LOG10;
              s[i][j] = exp(temp3);
           }
        }
     }

  /* Calculate Tone Masking Noise values */
     for(j=0;j<CBANDS;j++){
        temp1 = 15.5 + cbval[j];
        tmn[j] = (temp1>24.5) ? temp1 : 24.5;
  /* Calculate normalization factors for the net spreading functions */
        rnorm[j] = 0;
        for(i=0;i<CBANDS;i++){
           rnorm[j] += s[j][i];
        }
     }
     init++;
 }
 
/************************* End of Initialization *****************************/
 switch(lay) {
  case 1:
  case 2:
	for ( i=0; i<lay; i++)
  {
/*****************************************************************************
 * Net offset is 480 samples (1056-576) for layer 2; this is because one must*
 * stagger input data by 256 samples to synchronize psychoacoustic model with*
 * filter bank outputs, then stagger so that center of 1024 FFT window lines *
 * up with center of 576 "new" audio samples.                                *
 *                                                                           *
 * For layer 1, the input data still needs to be staggered by 256 samples,   *
 * then it must be staggered again so that the 384 "new" samples are centered*
 * in the 1024 FFT window.  The net offset is then 576 and you need 448 "new"*
 * samples for each iteration to keep the 384 samples of interest centered   *
 *****************************************************************************/
  for (j=0; j<syncsize; j++)
  {
    if (j < (sync_flush) )
      savebuf[j] = savebuf[j+flush];
    else
      savebuf[j] = *buffer++;

/**window data with HANN window***********************************************/
    if (j<BLKSIZE)
    {
      wsamp_r[j] = window[j]*((FLOAT) savebuf[j]); 
      wsamp_i[j] = 0;
    }
  }
/**Compute FFT****************************************************************/
        fft(wsamp_r,wsamp_i,energy,phi,1024);
/*****************************************************************************
 * calculate the unpredictability measure, given energy[f] and phi[f]        *
 *****************************************************************************/
        for(j=0; j<HBLKSIZE; j++){
           r_prime = 2.0 * r[chn][old][j] - r[chn][oldest][j];
           phi_prime = 2.0 * phi_sav[chn][old][j] - phi_sav[chn][oldest][j];
           r[chn][new][j] = sqrt((double) energy[j]);
           phi_sav[chn][new][j] = phi[j];
	   temp1 = r[chn][new][j] * cos((double) phi[j])
		   - r_prime * cos(phi_prime);
	   temp2=r[chn][new][j] * sin((double) phi[j])
		   - r_prime * sin(phi_prime);
           temp3=r[chn][new][j] + fabs(r_prime);
           if(temp3 != 0)c[j]=sqrt(temp1*temp1+temp2*temp2)/temp3;
           else c[j] = 0;
        }
/*only update data "age" pointers after you are done with the second channel */
/*for layer 1 computations, for the layer 2 double computations, the pointers*/
/*are reset automatically on the second pass                                 */
        if(lay==2 || chn==1){
           if(new==0){new = 1; oldest = 1;}
           else {new = 0; oldest = 0;}
           if(old==0)old = 1; else old = 0;
        }
/*****************************************************************************
 * Calculate the grouped, energy-weighted, unpredictability measure,         *
 * grouped_c[], and the grouped energy. grouped_e[]                          *
 *****************************************************************************/
        for(j=1;j<CBANDS;j++){
           grouped_e[j] = 0;
           grouped_c[j] = 0;
        }
        grouped_e[0] = energy[0];
        grouped_c[0] = energy[0]*c[0];
        for(j=1;j<HBLKSIZE;j++){
           grouped_e[partition[j]] += energy[j];
           grouped_c[partition[j]] += energy[j]*c[j];
        }
/*****************************************************************************
 * convolve the grouped energy-weighted unpredictability measure             *
 * and the grouped energy with the spreading function, s[j][k]               *
 *****************************************************************************/
        for(j=0;j<CBANDS;j++){