g729ev_fec_decbfi.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
*/

#include <stdlib.h>
#include <stdio.h>

#include "G729EV_MAIN_defines.h"
#include "G729EV_G729_defines.h"
#include "G729EV_FEC_fer.h"
#include "G729EV_FEC_tools.h"
#include "G729EV_G729_ld8k.h"
#include "stl.h"
#include "G729EV_MAIN_OPER_32B.h"
#include "G729EV_MAIN_DSPFUNC.h"

static void G729EV_FEC_synchro_exc(Word16 * exc, Word16 true_puls_pos, Word16 desire_puls_pos, Word16 Old_pitch);
static Word16 G729EV_FEC_enr_1_Az(  /* o:   impulse response energy */
                                   Word16 Aq[], /* i:   LP filter coefs         */
                                   Word16 len   /* i:   impulse response length */
    );
static void G729EV_FEC_syn_bfi(Word16 last_good, Word16 bfi_cnt, const Word16 stab_fac, Word16 * lp_gainp,
                               Word16 * lp_gainc, Word16 * exc_mem, Word16 * exc2, const Word16 T3,
                               const Word16 tilt_code, const Word16 Ts, Word16 * pitch_buf, const Word16 Tcnt,
                               Word16 * Aq, Word16 * synth, Word16 * mem_syn2, Word32 * Lenr_old, Word16 * seed,
                               Word16 * exc, Word16 puls_pos, Word16 new_pit);

/******************************************************************************/
/* G729EV_FEC_dec_bf : Frame erasure concealment                              */
/* Find LPC coefficient, pitch and reconstruct lost synthesis                 */
/******************************************************************************/
void G729EV_FEC_dec_bf(Word16 parm[],        /* (i)   : vector of synthesis parameters       */
                       Word16 synth[],       /* (i/o) : synthesis speech                     */
                       Word16 Az_dec[],      /* (o)   : decoded LP filter in 2 subframes     */
                       Word16 bfi,           /* (i)   : Bad Frame Indicator                  */
                       Word16 * last_good,   /* (i)   : last good frame classification       */
                       Word16 * pitch_buf,   /* (i/o) : Pitch memory                         */
                       Word16 old_enr,       /* (i)   : Energy at the end of the last frame  */
                       Word16 * old_exc,     /* (i/o) : excitiation memory                   */
                       G729EV_G729_DECSTAT * st,  /* (i)   : Decoder structure                    */
                       Word16 new_clas,      /* (i)   : present frame classification         */
                       Word16 puls_pos       /* (i)   : Position of the last pulse           */
    )
{

  Word16    A[G729EV_MAIN_NB_SUBFR * G729EV_G729_MP1];
  Word16    lsp_new[G729EV_G729_M];
  Word16   *exc, T3;
  Word16    exc2[G729EV_MAIN_L_FRAME2 + G729EV_FEC_L_FIR_FER - 1];
  Word16    exc_buf[G729EV_MAIN_L_FRAME2 + G729EV_G729_PIT_MAX + G729EV_G729_L_INTERPOL + G729EV_G729_L_SUBFR];
  Word16    T0, T0_frac;
  Word16    t0, t0_frac;
  Word16    index;

  T0 = (Word16) 0;
  T0_frac = (Word16) 0;
#if(WMOPS)
  move16();
  move16();
#endif
  exc = exc_buf + G729EV_G729_PIT_MAX + G729EV_G729_L_INTERPOL;

  G729EV_G729_Copy(old_exc, exc_buf, G729EV_G729_PIT_MAX + G729EV_G729_L_INTERPOL);

  /* Decode the LSPs */
  G729EV_G729_D_lsp(st->freq_prev, st->prev_lsp, &(st->prev_ma), parm, lsp_new, bfi);
  parm += 2;


  IF(sub(bfi, G729EV_FEC_SINGLE_FRAME) == 0)
  {
    index = *parm++;            /* pitch index */
#if(WMOPS)
    move16();
    move16();
#endif
    /* decode future pitch */
    G729EV_G729_Dec_lag3(index, G729EV_G729_PIT_MIN, G729EV_G729_PIT_MAX, 0, &t0, &t0_frac);

    G729EV_G729_Int_qlpc_bfi(st->lsp_old, lsp_new, A, interpol_frac2);
    G729EV_G729_Copy(A, Az_dec, G729EV_MAIN_NB_SUBFR * G729EV_G729_MP1);

    /* update the LSFs for the next frame */
    G729EV_G729_Copy(lsp_new, st->lsp_old, G729EV_G729_M);
    G729EV_FEC_pitch_pred(1, &T0, &T0_frac, st->pit_mem, &(st->bfi_mem));
    T3 = st->pit_mem[3];
    /*t0 = true future pitch */
  }
  ELSE
  {
    /* Interpolation of LPC for the 4 subframes */
    G729EV_G729_Int_qlpc_bfi(st->lsp_old, lsp_new, A, interpol_frac2);
    G729EV_G729_Copy(A, Az_dec, G729EV_MAIN_NB_SUBFR * G729EV_G729_MP1);

    /* update the LSFs for the next frame */
    G729EV_G729_Copy(lsp_new, st->lsp_old, G729EV_G729_M);
    G729EV_FEC_pitch_pred(1, &T0, &T0_frac, st->pit_mem, &(st->bfi_mem));
    T3 = st->pit_mem[3];
    t0 = T0;                    /* t0 = predicted pitch */
#if(WMOPS)
    move16();
    move16();
#endif
  }


   /*-------------------------------------------------*
    * Find the excitation and synthesize speech
    *-------------------------------------------------*/
  G729EV_FEC_syn_bfi(*last_good, st->bfi_cnt, st->stab_fac, &st->lp_gainp, &st->lp_gainc, st->old_exc, exc2,
                     T3, st->tilt_code, st->old_fpitch, pitch_buf, st->upd_cnt,
                     A, synth, st->mem_syn, &(st->Lenr_old), &(st->seed_fer), exc, puls_pos, t0);



   /*------------------------------------------------*
    Others updates
    --------------------------------------------------*/

  G729EV_G729_Copy(&exc[G729EV_MAIN_L_FRAME2 - G729EV_G729_PIT_MAX - G729EV_G729_L_INTERPOL], st->old_exc,
                   G729EV_G729_PIT_MAX + G729EV_G729_L_INTERPOL);
  st->upd_cnt = add(st->upd_cnt, 1);  /* counter of the age of the last update */
  if (sub(st->upd_cnt, G729EV_FEC_MAX_UPD_CNT) > 0)
  {
    st->upd_cnt = G729EV_FEC_MAX_UPD_CNT;
#if(WMOPS)
    move16();
#endif
  }
   /*----------------------------------------------------------------------*
    * Update for next frame.                           
    *----------------------------------------------------------------------*/
}

/******************************************************************************/
/* G729EV_FEC_syn_bfi : Reconstruction of erased frame                        */
/* - Find pitch                                                               */
/* - Estimate damping factor                                                  */
/* - Construct and synchronize periodic part of excitation                    */
/* - Construct random part of excitation                                      */
/* - Apply gain to excitation                                                 */
/* - Do synthesis filtering to recover lost synthesis                         */
/******************************************************************************/
static void G729EV_FEC_syn_bfi(Word16 last_good,       /* i:   last good frame clas                    */
                               Word16 bfi_cnt,         /* i:   counter of consecutive bfi frames       */
                               const Word16 stab_fac,  /* i:   ISF stability measure                   */
                               Word16 * lp_gainp,      /* i/o: damped pitch gain                       */
                               Word16 * lp_gainc,      /* i/o: damped code gain                        */
                               Word16 * exc_mem,       /* o:   excitation memory (st->old_exc)         */
                               Word16 * exc2,          /* o:   excitation buffer (for synthesis)       */
                               const Word16 T3,        /* i:   floating pitch                          */
                               const Word16 tilt_code, /* i:   spectral tilt                           */
                               const Word16 Ts,        /* i:   previous pitch for hr G729EV_FEC_VOICED */
                               Word16 * pitch_buf,     /* o:   floating pitch for every subfr          */
                               const Word16 Tcnt,      /* i:   counter of the last bfi pitch updt.     */
                               Word16 * Aq,            /* i    LP filter coefs                         */
                               Word16 * synth,         /* o    synthesized speech at Fs = 16kHz        */
                               Word16 * mem_syn2,      /* i/o  initial synthesis filter states         */
                               Word32 * Lenr_old,      /* o    energy update at the end for next frame */
                               Word16 * seed,          /* i/o: random generator seed                   */
                               Word16 * exc,           /* i/o: pointer to present exc                  */
                               Word16 puls_pos,        /* i  : Pulse position                          */
                               Word16 new_pit          /* i  : Pitch of the first future frame         */
    )
{
  Word16    i, i_subfr;
  Word16    pit_subfr;
  Word16    nb_pusles, pulse_chosen, Terr;
  Word16    P0 = 0, pit_search, diff_pit, sign;
  Word32    L_tmp, L_tmp2, L_step;
  Word16    hp_filt[5], tmp2, *p_Az, exp_alpha, exp_gain, j;
  Word16    delta, fT0, pos, total_pit_lag = 0;
  Word16   *pt_exc, *pt1_exc, alpha, step, gain_inov, gain, tmp16, tmp_Tc, Tc;
  Word16    dist_Plast, Plast, Tlist[10];

   /*------------------------------------------------------------------------------------------*
    * Find secure pitch estimation for FERs
    * The new_pit is always known 
    * in single FER, new_pit is the futur pitch else new_pit is predict from past pitch
    *------------------------------------------------------------------------------------------*/
  sign = 0;
#if(WMOPS)
  move16();
  move16();
  test();
  test();
#endif

  IF(((sub(Ts, shl(mult(29491, T3), 1)) < 0) && (sub(Ts, mult(19661, T3)) > 0)) ||  /* last pitch coherent with the past  */
     (sub(Tcnt, G729EV_FEC_MAX_UPD_CNT) >= 0))  /* or last update too far in the past */
  {
    tmp_Tc = T3;                /*pitch period of the 4th subframe of the last good frame */
  }
  ELSE
  {
    tmp_Tc = Ts;                /* pitch period of the 4th subframe of the last good STABLE VOICED */
  }

  IF(new_pit > 0)
  {
#if(WMOPS)
    move16();
#endif
    fT0 = tmp_Tc;
    delta = shr(sub(shl(new_pit, G729EV_FEC_SQPIT), fT0), 2); /* 4 sub-frames */
    FOR(i = 0; i < 4; i++)     /* subframe pitch values */
    {
      fT0 = add(fT0, delta);
      pitch_buf[i] = shl(shr(add(fT0, G729EV_FEC_QPIT2), G729EV_FEC_SQPIT), G729EV_FEC_SQPIT);
#if(WMOPS)
      move16();
#endif
    }
  }
  ELSE                          /* Should never happen in normal processing condition */
  {
    FOR(i = 0; i < 4; i++)
    {
      pitch_buf[i] = tmp_Tc;
#if(WMOPS)
      move16();
#endif
    }
  }

   /*-------------------------------------------------*
    * hp filter random part and add to excitation   
    *-------------------------------------------------*/
  tmp2 = sub(32767, tilt_code);
  FOR(i = 0; i < G729EV_FEC_L_FIR_FER; i++)
  {
    /*hp_filt[i] = (1.0f - tilt_code) * G729EV_FEC_h_high[i]; */
    hp_filt[i] = mult_r(tmp2, G729EV_FEC_h_high[i]);
#if(WMOPS)
    move16();
#endif
  }

   /*-------------------------------------------------*
    * Estimate damping factor                         *
    *-------------------------------------------------*/
#if(WMOPS)
  move16();
#endif
  IF(sub(last_good, G729EV_FEC_UNVOICED) == 0)
  {
    IF(sub(bfi_cnt, 3) > 0)
    {                           /* If stable, do not decrease the energy */
      /*alpha = (stab_fac * (0.9f - G729EV_FEC_ALPHA_U) + G729EV_FEC_ALPHA_U); */
      alpha = G729EV_FEC_ALPHA_VT;
    }
    ELSE      IF(sub(bfi_cnt, 1) > 0)
    {                           /* If stable, do not decrease the energy */
      /*alpha = (stab_fac * (0.9f - G729EV_FEC_ALPHA_U) + G729EV_FEC_ALPHA_U); */
      alpha = add(mult_r(stab_fac, (32767 - G729EV_FEC_ALPHA_U)), G729EV_FEC_ALPHA_U);
    }
    ELSE
    {
      alpha = G729EV_FEC_ALPHA_U2;
    }
  }
  ELSE if   (sub(last_good, G729EV_FEC_UV_TRANSITION) == 0)
  {
    alpha = G729EV_FEC_ALPHA_UT;
  }
  ELSE if   ((sub(last_good, G729EV_FEC_ONSET) == 0))
  {
    alpha = 26214;              /* mild convergence to 0 for the first 3 erased frames */
  }
  ELSE if   (((sub(last_good, G729EV_FEC_VOICED) == 0) || (sub(last_good, G729EV_FEC_ONSET) == 0)))
  {
    alpha = G729EV_FEC_ALPHA_V; /* constant for the first 3 erased frames */
  }
  ELSE if   (sub(last_good, G729EV_FEC_SIN_ONSET) == 0)
  {
    alpha = G729EV_FEC_ALPHA_S;
  }
  ELSE                          /* G729EV_FEC_V_TRANSITION */
  {
    IF((sub(bfi_cnt, 2) <= 0))
    {
      alpha = 2 * G729EV_FEC_ALPHA_VT;  /* medium convergence to 0  */
    }
    ELSE
    {
      alpha = (Word16) 6654;    /* very fast convergence to 0  */
    }
  }

  IF(sub(last_good, G729EV_FEC_VOICED) >= 0)
  {
    IF(sub(bfi_cnt, 1) == 0)    /* if first erased frame in a block, reset harmonic gain */
    {
      /*gain = (float)sqrt( *lp_gainp ); *//* move pitch gain towards 1 for G729EV_FEC_VOICED to remove energy fluctuations */
      if(*lp_gainp == 0)
      {
        *lp_gainp = 1;
      }
      exp_alpha = norm_s(*lp_gainp);
      tmp2 = shl(*lp_gainp, exp_alpha);
      tmp2 = div_s(16384, tmp2);
      L_tmp = L_deposit_h(tmp2);
      Isqrt_n(&L_tmp, &exp_alpha);

      gain = extract_h(L_shl(L_tmp, exp_alpha));
#if(WMOPS)
      move16();
      move32();
#endif
      IF(sub(gain, 32113) > 0)  /*.98 */
      {
        gain = (Word16) 32113;
#if(WMOPS)
        move16();
#endif
      }
      ELSE if   (sub(gain, 27853) < 0)  /*0.85 */
      {
        gain = (Word16) 27853;
#if(WMOPS)
        move16();
#endif
      }
      alpha = mult_r(alpha, gain);
    }
    ELSE      IF(bfi_cnt <= 3)
    {
      /* in Q15 */
      alpha = shl(*lp_gainp, 1);
    }
    ELSE
    {
      alpha = G729EV_FEC_ALPHA_VT;
    }
  }
  IF(sub(last_good, G729EV_FEC_UV_TRANSITION) >= 0)
  {
    /* Tc = (short)(bfi_pitch + 0.5f); */
    Tc = shr(add(tmp_Tc, G729EV_FEC_QPIT2), G729EV_FEC_SQPIT);
#if(WMOPS)
    move16();
#endif
       /*-------------------------------------------------*
        * Construct the periodic part of excitation       *
        *-------------------------------------------------*/
    pt_exc = exc;
    pt1_exc = exc - Tc;
    pos = (Word16) 0;
    IF(sub(bfi_cnt, 1) == 0)    /* if 1st erased frame after a good frame */
    {
      FOR(i = 0; i < Tc; i++)  /* pitch cycle is first low-pass filtered */
      {
        /* *pt_exc++ = ( 0.18f * pt1_exc[-1] + 0.64f * pt1_exc[0] + 0.18f * pt1_exc[1] ); */
        L_tmp = L_mult(5898, pt1_exc[-1]);
        L_tmp = L_mac(L_tmp, 20972, pt1_exc[0]);
        L_tmp = L_mac(L_tmp, 5898, pt1_exc[1]);
        *pt_exc = round(L_tmp);
        pt_exc++;
        pt1_exc++;
#if(WMOPS)