g729ev_g729_pst.c

最新的ITU-T的宽带语音编解码标准G.729.1,是对原先的G.729的最好的调整.码流输出速率可以进行自适应调整.满足未来通信要求.希望对大家有所帮助.

/* ITU-T G.729EV Optimization/Characterization Candidate                         */
/* Version:       1.0.a                                                          */
/* Revision Date: June 28, 2006                                                  */

/*
   ITU-T G.729EV Optimization/Characterization Candidate    ANSI-C Source Code
   Copyright (c) 2006 
   France Telecom, Matsushita Electric, Mindspeed, Siemens AG, ETRI, VoiceAge Corp.
   All rights reserved
*/

/************************************************************************/
/*      Post - filtering : short term + long term                       */
/************************************************************************/

#include "stl.h"
#include "G729EV_G729_ld8k.h"
#include "G729EV_MAIN_OPER_32B.h"


/*----------------------------------------------------------------------------
 *  G729EV_G729_pst_ltp - harmonic postfilter
 *----------------------------------------------------------------------------
 */
void G729EV_G729_pst_ltp(Word16 t0,             /* input : pitch delay given by coder */
                         Word16 * ptr_sig_in,   /* input : postfilter input filter (residu2) */
                         Word16 * ptr_sig_pst0  /* output: harmonic postfilter output */
    )
{

/**** Declare variables                                 */
  Word32    L_temp;

  Word16    y_up[G729EV_G729_SIZ_Y_UP];
  Word16    sig_cadr[G729EV_G729_SIZ_RES2];

  Word16   *ptr_y_up;
  Word16   *ptr_sig;
  Word16   *ptr_sig_cadr;

  Word16    i;
  Word16    temp;
  Word16    ltpdel, phase;
  Word16    num_gltp, den_gltp;
  Word16    num2_gltp, den2_gltp;
  Word16    sh_num, sh_den;
  Word16    sh_num2, sh_den2;
  Word16    gain_plt;
  Word16    off_yup;
  Word16    nb_sh_sig;


  /* input signal justified on 13 bits */
#if (WMOPS)
  move16();
#endif
  ptr_sig = ptr_sig_in - G729EV_G729_MEM_RES2;

  temp = 0;
  FOR(i = 0; i < G729EV_G729_SIZ_RES2; i++)
  {
    temp = s_or(temp, abs_s(ptr_sig[i]));
  }
  nb_sh_sig = sub(3, norm_s(temp));

  FOR(i = 0; i < G729EV_G729_SIZ_RES2; i++)
  {                             /* nb_sh_sig may be >0, <0 or =0 */
#if (WMOPS)
    move16();
#endif
    sig_cadr[i] = shr(ptr_sig[i], nb_sh_sig);
  }
  ptr_sig_cadr = sig_cadr + G729EV_G729_MEM_RES2;

  /* Sub optimal delay search */
  G729EV_G729_search_del(t0, ptr_sig_cadr, &ltpdel, &phase, &num_gltp, &den_gltp, &sh_num, &sh_den, y_up, &off_yup);

  IF(num_gltp == 0)
  {
    G729EV_G729_Copy(ptr_sig_in, ptr_sig_pst0, G729EV_G729_L_SUBFR);
  }

  ELSE
  {
    IF(phase == 0)
    {
      ptr_y_up = ptr_sig_in - ltpdel;
    }

    ELSE
    {

      /* Filtering with long filter */
      G729EV_G729_compute_ltp_l(ptr_sig_cadr, ltpdel, phase, ptr_sig_pst0, &num2_gltp, &den2_gltp, &sh_num2, &sh_den2);

      IF(sub(G729EV_G729_select_ltp(num_gltp, den_gltp, sh_num, sh_den, num2_gltp, den2_gltp, sh_num2, sh_den2), 1) ==
         0)
      {

        /* select short filter */
        temp = sub(phase, 1);
        L_temp = L_mult(temp, G729EV_G729_L_SUBFRP1);
        L_temp = L_shr(L_temp, 1);
        temp = extract_l(L_temp);
        temp = add(temp, off_yup);

        /* ptr_y_up = y_up + (phase-1) * G729EV_G729_L_SUBFRP1 + off_yup */
        ptr_y_up = y_up + temp;
      }
      ELSE
      {
#if (WMOPS)
        move16();
        move16();
        move16();
        move16();
#endif
        /* select long filter */
        num_gltp = num2_gltp;
        den_gltp = den2_gltp;
        sh_num = sh_num2;
        sh_den = sh_den2;
        ptr_y_up = ptr_sig_pst0;
      }

      /* rescale y_up */
      FOR(i = 0; i < G729EV_G729_L_SUBFR; i++)
      {                         /* nb_sh_sig may be >0, <0 or =0 */
#if (WMOPS)
        move16();
#endif
        ptr_y_up[i] = shl(ptr_y_up[i], nb_sh_sig);
      }
    }

    temp = sub(sh_num, sh_den);
    IF(temp >= 0)
    {
      den_gltp = shr(den_gltp, temp);
    }
    ELSE
    {
      num_gltp = shl(num_gltp, temp); /*  >> (-temp) */
    }
    IF(sub(num_gltp, den_gltp) >= 0)
    {
#if (WMOPS)
      move16();
#endif
      /* beta bounded to 1 */
      gain_plt = G729EV_G729_MIN_GPLT;
    }
    ELSE
    {

      /* GAMMA_G = 0.5                                            */
      /* gain_plt = den_gltp x 2**15 / (den_gltp + 0.5 num_gltp)  */
      /* shift 1 bit to avoid overflows in add                    */
      num_gltp = shr(num_gltp, 2);
      den_gltp = shr(den_gltp, 1);
      temp = add(den_gltp, num_gltp);
      gain_plt = div_s(den_gltp, temp); /* Q15 */
    }

        /** filtering by H0(z) = harmonic filter **/
    G729EV_G729_filt_plt(ptr_sig_in, ptr_y_up, ptr_sig_pst0, gain_plt);

  }

  return;
}

/*----------------------------------------------------------------------------
 *  search_del: computes best (shortest) integer LTP delay + fine search
 *----------------------------------------------------------------------------
 */
void G729EV_G729_search_del(Word16 t0,            /* input : pitch delay given by coder */
                            Word16 * ptr_sig_in,  /* input : input signal (with delay line) */
                            Word16 * ltpdel,      /* output: delay = *ltpdel - *phase / f_up */
                            Word16 * phase,       /* output: phase */
                            Word16 * num_gltp,    /* output: 16 bits numerator of LTP gain */
                            Word16 * den_gltp,    /* output: 16 bits denominator of LTP gain */
                            Word16 * sh_num_gltp, /* output: justification for num_gltp */
                            Word16 * sh_den_gltp, /* output: justification for den_gltp */
                            Word16 * y_up,        /* output: LT delayed signal if fract. delay */
                            Word16 * off_yup      /* output: offset in y_up */
    )
{



  Word32    L_den0[G729EV_G729_F_UP_PST - 1];
  Word32    L_den1[G729EV_G729_F_UP_PST - 1];

  Word32   *ptr_L_den0, *ptr_L_den1;

  Word32    L_num_int, L_den_int, L_den_max;
  Word32    L_temp0, L_temp1;
  Word32    L_acc;
  Word32    L_temp;

  extern Word16 tab_hup_s[G729EV_G729_SIZ_TAB_HUP_S];

  Word16   *ptr_h;
  Word16   *ptr_sig_past, *ptr_sig_past0;
  Word16   *ptr1, *ptr_y_up;

  Word16    i, n;
  Word16    num, den0, den1;
  Word16    den_max, num_max;
  Word16    hi_numsq, hi_numsq_max;
  Word16    lo_numsq, lo_numsq_max;
  Word16    ener;
  Word16    sh_num, sh_den, sh_ener;
  Word16    i_max, lambda, phi, phi_max, ioff;
  Word16    temp;


  /*************************************/
  /* Computes energy of current signal */
    /*************************************/

#if (WMOPS)
  move32();
#endif
  L_acc = 0L;

  FOR(i = 0; i < G729EV_G729_L_SUBFR; i++)
  {
    L_acc = L_mac(L_acc, ptr_sig_in[i], ptr_sig_in[i]);
  }
  if (L_acc == 0)
  {
#if (WMOPS)
    move16();
    move16();
    move16();
    move16();
#endif
    *num_gltp = 0;
    *den_gltp = 1;
    *ltpdel = 0;
    *phase = 0;
    return;
  }
  sh_ener = sub(16, norm_l(L_acc));
  /* save energy for final decision */
  IF(sh_ener > 0)
  {
    ener = extract_l(L_shr(L_acc, sh_ener));
  }
  ELSE
  {
#if (WMOPS)
    move16();
#endif
    sh_ener = 0;
    ener = extract_l(L_acc);
  }

    /*************************************/
  /* Selects best of 3 integer delays  */
  /* Maximum of 3 numerators around t0 */
    /*************************************/
#if (WMOPS)
  move16();
  move32();
#endif
  lambda = sub(t0, 1);
  ptr_sig_past = ptr_sig_in - lambda;
  L_num_int = -1L;

  /* initialization used only to suppress Microsoft Visual C++ warnings */
#if (WMOPS)
  move16();
#endif
  i_max = (Word16) 0;

  FOR(i = 0; i < 3; i++)
  {
#if (WMOPS)
    move32();
#endif
    L_acc = 0L;
    FOR(n = 0; n < G729EV_G729_L_SUBFR; n++)
    {
      L_acc = L_mac(L_acc, ptr_sig_in[n], ptr_sig_past[n]);
    }
    if (L_acc < 0)
    {
#if (WMOPS)
      move32();
#endif
      L_acc = 0L;
    }
    L_temp = L_sub(L_acc, L_num_int);
    if (L_temp > 0L)
    {
#if (WMOPS)
      move16();
      move32();
#endif
      L_num_int = L_acc;
      i_max = (Word16) i;
    }
    ptr_sig_past--;
  }

  if (L_num_int == 0)
  {
#if (WMOPS)
    move16();
    move16();
    move16();
    move16();
#endif
    *num_gltp = 0;
    *den_gltp = 1;
    *ltpdel = 0;
    *phase = 0;
    return;
  }

  /* Compute den for i_max */
  lambda = add(lambda, (Word16) i_max);
#if (WMOPS)
  move32();
#endif
  ptr_sig_past = ptr_sig_in - lambda;
  L_acc = 0L;
  FOR(i = 0; i < G729EV_G729_L_SUBFR; i++)
  {
#if (WMOPS)
    move16();
#endif
    temp = *ptr_sig_past++;
    L_acc = L_mac(L_acc, temp, temp);
  }
  if (L_acc == 0L)
  {
#if (WMOPS)
    move16();
    move16();
    move16();
    move16();
#endif
    *num_gltp = 0;
    *den_gltp = 1;
    *ltpdel = 0;
    *phase = 0;
    return;
  }
#if (WMOPS)
  move32();
#endif
  L_den_int = L_acc;


    /***********************************/
  /* Select best phase around lambda */
    /***********************************/

  /* Compute y_up & denominators */
    /*******************************/

#if (WMOPS)
  move32();
#endif
  ptr_y_up = y_up;
  L_den_max = L_den_int;
  ptr_L_den0 = L_den0;
  ptr_L_den1 = L_den1;
  ptr_h = tab_hup_s;
  temp = sub(lambda, G729EV_G729_LH_UP_SM1);
  ptr_sig_past0 = ptr_sig_in - temp;

  /* Loop on phase */
  FOR(phi = 1; phi < G729EV_G729_F_UP_PST; phi++)
  {

    /* Compute y_up for lambda+1 - phi/F_UP_PST */
    /* and lambda - phi/F_UP_PST                */

    ptr_sig_past = ptr_sig_past0;
    FOR(n = 0; n <= G729EV_G729_L_SUBFR; n++)
    {
#if (WMOPS)
      move16();
      move32();
#endif
      ptr1 = ptr_sig_past++;
      L_acc = 0L;

      FOR(i = 0; i < G729EV_G729_LH2_S; i++)
      {
        L_acc = L_mac(L_acc, ptr_h[i], ptr1[-i]);
      }
#if (WMOPS)
      move16();
#endif
      ptr_y_up[n] = round(L_acc);
    }

    /* compute den0 (lambda+1) and den1 (lambda) */

    /* part common to den0 and den1 */
#if (WMOPS)
    move32();
#endif
    L_acc = 0L;
    FOR(n = 1; n < G729EV_G729_L_SUBFR; n++)
    {
      L_acc = L_mac(L_acc, ptr_y_up[n], ptr_y_up[n]);
    }
#if (WMOPS)
    move32();
#endif
    L_temp0 = L_acc;            /* saved for den1 */

    /* den0 */
    L_acc = L_mac(L_acc, ptr_y_up[0], ptr_y_up[0]);
#if (WMOPS)
    move32();
#endif
    *ptr_L_den0 = L_acc;

    /* den1 */
    L_acc = L_mac(L_temp0, ptr_y_up[G729EV_G729_L_SUBFR], ptr_y_up[G729EV_G729_L_SUBFR]);
#if (WMOPS)
    move32();
#endif
    *ptr_L_den1 = L_acc;

    IF(sub(abs_s(ptr_y_up[0]), abs_s(ptr_y_up[G729EV_G729_L_SUBFR])) > 0)
    {
      L_temp = L_sub(*ptr_L_den0, L_den_max);
      if (L_temp > 0L)
      {
#if (WMOPS)
        move32();
#endif
        L_den_max = *ptr_L_den0;