path: root/libtoolame-dab/psycho_2.c

#include <stdio.h>
#include <stdlib.h>
#include <math.h>
#include <string.h>
#include "common.h"
#include "encoder.h"
#include "mem.h"
#include "fft.h"
#include "psycho_2.h"

/* 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 int new = 0, old = 1, oldest = 0;
static int init = 0, flush, sync_flush, syncsize, sfreq_idx;

/* 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
};

static FLOAT *grouped_c, *grouped_e, *nb, *cb, *ecb, *bc;
static FLOAT *wsamp_r, *phi, *energy;
static FLOAT *c, *fthr;
static 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;

void psycho_2_init (double sfreq);

void psycho_2 (short int *buffer, short int savebuf[1056], int chn,
		double *smr, double sfreq, options *glopts)
/* to match prototype : FLOAT args are always double */
{
  unsigned int i, j, k;
  FLOAT r_prime, phi_prime;
  FLOAT minthres, sum_energy;
  double tb, temp1, temp2, temp3;

  if (init == 0) {
    psycho_2_init (sfreq);
    init++;
  }

  for (i = 0; i < 2; 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.                                *
       
           flush = 384*3.0/2.0;  = 576
           syncsize = 1056;
           sync_flush = syncsize - flush;   480
           BLKSIZE = 1024
       *****************************************************************************/

    for (j = 0; j < 480; j++) {
      savebuf[j] = savebuf[j + flush];
      wsamp_r[j] = window[j] * ((FLOAT) savebuf[j]);
    }
    for (; j < 1024; j++) {
      savebuf[j] = *buffer++;
      wsamp_r[j] = window[j] * ((FLOAT) savebuf[j]);
    }
    for (; j < 1056; j++)
      savebuf[j] = *buffer++;

      /**Compute FFT****************************************************************/
    psycho_2_fft (wsamp_r, energy, phi);
      /*****************************************************************************
       * calculate the unpredictability measure, given energy[f] and phi[f]        *
       *****************************************************************************/
    /*only update data "age" pointers after you are done with both channels      */
    /*for layer 1 computations, for the layer 2 double computations, the pointers */
    /*are reset automatically on the second pass                                 */
    {
      if (new == 0) {
	new = 1;
	oldest = 1;
      } else {
	new = 0;
	oldest = 0;
      }
      if (old == 0)
	old = 1;
      else
	old = 0;
    }
    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];
#ifdef SINCOS
      {
	// 12% faster
	//#warning "Use __sincos"
	double sphi, cphi, sprime, cprime;
	__sincos ((double) phi[j], &sphi, &cphi);
	__sincos ((double) phi_prime, &sprime, &cprime);
	temp1 = r[chn][new][j] * cphi - r_prime * cprime;
	temp2 = r[chn][new][j] * sphi - r_prime * sprime;
      }
#else
      temp1 =
	r[chn][new][j] * cos ((double) phi[j]) -
	r_prime * cos ((double) phi_prime);
      temp2 =
	r[chn][new][j] * sin ((double) phi[j]) -
	r_prime * sin ((double) phi_prime);
#endif

      temp3 = r[chn][new][j] + fabs ((double) r_prime);
      if (temp3 != 0)
	c[j] = sqrt (temp1 * temp1 + temp2 * temp2) / temp3;
      else
	c[j] = 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++) {
      ecb[j] = 0;
      cb[j] = 0;
      for (k = 0; k < CBANDS; k++) {
	if (s[j][k] != 0.0) {
	  ecb[j] += s[j][k] * grouped_e[k];
	  cb[j] += s[j][k] * grouped_c[k];
	}
      }
      if (ecb[j] != 0)
	cb[j] = cb[j] / ecb[j];
      else
	cb[j] = 0;
    }

      /*****************************************************************************
       * Calculate the required SNR for each of the frequency partitions           *
       *         this whole section can be accomplished by a table lookup          *
       *****************************************************************************/
    for (j = 0; j < CBANDS; j++) {
      if (cb[j] < .05)
	cb[j] = 0.05;
      else if (cb[j] > .5)
	cb[j] = 0.5;
      tb = -0.434294482 * log ((double) cb[j]) - 0.301029996;
      cb[j] = tb;
      bc[j] = tmn[j] * tb + nmt * (1.0 - tb);
      k = cbval[j] + 0.5;
      bc[j] = (bc[j] > bmax[k]) ? bc[j] : bmax[k];
      bc[j] = exp ((double) -bc[j] * LN_TO_LOG10);
    }

      /*****************************************************************************
       * Calculate the permissible noise energy level in each of the frequency     *
       * partitions. Include absolute threshold and pre-echo controls              *
       *         this whole section can be accomplished by a table lookup          *
       *****************************************************************************/
    for (j = 0; j < CBANDS; j++)
      if (rnorm[j] && numlines[j])
	nb[j] = ecb[j] * bc[j] / (rnorm[j] * numlines[j]);
      else
	nb[j] = 0;
    for (j = 0; j < HBLKSIZE; j++) {
      /*temp1 is the preliminary threshold */
      temp1 = nb[partition[j]];
      temp1 = (temp1 > absthr[j]) ? temp1 : absthr[j];
#ifdef LAYERI
      /*do not use pre-echo control for layer 2 because it may do bad things to the */
      /*  MUSICAM bit allocation algorithm                                         */
      if (lay == 1) {
	fthr[j] = (temp1 < lthr[chn][j]) ? temp1 : lthr[chn][j];
	temp2 = temp1 * 0.00316;
	fthr[j] = (temp2 > fthr[j]) ? temp2 : fthr[j];
      } else
	fthr[j] = temp1;
      lthr[chn][j] = LXMIN * temp1;
#else
      fthr[j] = temp1;
      lthr[chn][j] = LXMIN * temp1;
#endif
    }

      /*****************************************************************************
       * Translate the 512 threshold values to the 32 filter bands of the coder    *
       *****************************************************************************/
    for (j = 0; j < 193; j += 16) {
      minthres = 60802371420160.0;
      sum_energy = 0.0;
      for (k = 0; k < 17; k++) {
	if (minthres > fthr[j + k])
	  minthres = fthr[j + k];
	sum_energy += energy[j + k];
      }
      snrtmp[i][j / 16] = sum_energy / (minthres * 17.0);
      snrtmp[i][j / 16] = 4.342944819 * log ((double) snrtmp[i][j / 16]);
    }
    for (j = 208; j < (HBLKSIZE - 1); j += 16) {
      minthres = 0.0;
      sum_energy = 0.0;
      for (k = 0; k < 17; k++) {
	minthres += fthr[j + k];
	sum_energy += energy[j + k];
      }
      snrtmp[i][j / 16] = sum_energy / minthres;
      snrtmp[i][j / 16] = 4.342944819 * log ((double) snrtmp[i][j / 16]);
    }
      /*****************************************************************************
       * End of Psychoacuostic calculation loop                                    *
       *****************************************************************************/
  }
  for (i = 0; i < 32; i++) {
    smr[i] = (snrtmp[0][i] > snrtmp[1][i]) ? snrtmp[0][i] : snrtmp[1][i];
  }
}

/********************************
 * init psycho model 2
 ********************************/
void psycho_2_init (double sfreq)
{
  int i, j;
  FLOAT freq_mult;
  double temp1, temp2, temp3;
  FLOAT bval_lo;

  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");
  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");

  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");

  i = sfreq + 0.5;
  switch (i) {
  case 32000:
  case 16000:
    sfreq_idx = 0;
    break;
  case 44100:
  case 22050:
    sfreq_idx = 1;
    break;
  case 48000:
  case 24000:
    sfreq_idx = 2;
    break;
  default:
    fprintf (stderr, "error, invalid sampling frequency: %d Hz\n", i);
    exit (-1);
  }
  fprintf (stderr, "absthr[][] sampling frequency index: %d\n", sfreq_idx);
  psycho_2_read_absthr (absthr, sfreq_idx);

  flush = 384 * 3.0 / 2.0;
  syncsize = 1056;
  sync_flush = syncsize - flush;

  /* 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));
  /* 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];
    }
  }

  if (glopts.verbosity > 10){
    /* Dump All the Values to STDOUT and exit */
    int wlow, whigh=0;
    fprintf(stdout,"psy model 2 init\n");
    fprintf(stdout,"index \tnlines \twlow \twhigh \tbval \tminval \ttmn\n");
    for (i=0;i<CBANDS;i++) {
      wlow = whigh+1;
      whigh = wlow + numlines[i] - 1;
      fprintf(stdout,"%i \t%i \t%i \t%i \t%5.2f \t%4.2f \t%4.2f\n",i+1, numlines[i],wlow, whigh, cbval[i],bmax[(int)(cbval[i]+0.5)],tmn[i]);
    }
    exit(0);
  }

}

void psycho_2_read_absthr (absthr, table)
     FLOAT *absthr;
     int table;
{
  int j;
#include "absthr.h"

  if ((table < 0) || (table > 3)) {
    printf ("internal error: wrong table number");
    return;
  }

  for (j = 0; j < HBLKSIZE; j++) {
    absthr[j] = absthr_table[table][j];
  }
  return;
}