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.

      L_tmp = L_mac(L_tmp, hp_filt[2], pt_exc[2]);
      L_tmp = L_mac(L_tmp, hp_filt[3], pt_exc[3]);
      L_tmp = L_mac(L_tmp, hp_filt[4], pt_exc[4]);
      pt_exc++;
      exc[i] = add(exc[i], round(L_tmp));
      move16();
#if(WMOPS)
      move16();
#endif
    }
  }
  ELSE
  {
    G729EV_G729_Copy(exc2 + G729EV_FEC_L_FIR_FER / 2, exc, G729EV_MAIN_L_FRAME2); /* For purely G729EV_FEC_UNVOICED, just G729EV_G729_copy the random part */
    G729EV_G729_Copy(&exc[G729EV_MAIN_L_FRAME2 - G729EV_FEC_L_EXC_MEM], exc_mem, G729EV_FEC_L_EXC_MEM); /* Update old_exc                                 */
  }

  G729EV_G729_Copy(exc, exc2, G729EV_MAIN_L_FRAME2);  /* Update exc2       */


   /*------------------------------------------------------------*
     Speech synthesis 
    *------------------------------------------------------------*/
  p_Az = Aq;
  FOR(i_subfr = 0; i_subfr < G729EV_MAIN_L_FRAME2; i_subfr += G729EV_G729_L_SUBFR)
  {
    G729EV_G729_Syn_filt2(p_Az, &exc2[i_subfr], &synth[i_subfr], G729EV_G729_L_SUBFR, mem_syn2, 1);
    p_Az += (G729EV_G729_M + 1);
  }

   /*------------------------------------------------------------------*
    * estimate the pitch-synchronous speech energy per sample          *
    * to be used when normal operation recovers                        *
    *------------------------------------------------------------------*/

  tmp16 = G729EV_FEC_energy(last_good, synth, shr(add(tmp_Tc, G729EV_FEC_QPIT2), G729EV_FEC_SQPIT), Lenr_old, 1);
  IF(sub(last_good, G729EV_FEC_VOICED) < 0)
  {
    /* Convert energy to Q0 */
    *Lenr_old = L_mls(*Lenr_old, 26214);
    tmp16 = add(tmp16, 6 + 1);
    *Lenr_old = L_shr_r(*Lenr_old, tmp16);
#if(WMOPS)
    move32();
    move32();
#endif
  }
  return;
}

/*************************************************************************************/
/* G729EV_FEC_scale_syn : Smooth energy transition between lost frame and good frame */
/* - Find energy at frame end                                                        */
/* - Find energy at frame beginning                                                  */
/* - smooth excitation energy over all the frame                                     */
/* - redo synthesis (if needed)                                                      */
/*************************************************************************************/
void G729EV_FEC_scale_syn(Word16 extrate,          /* i: indicate decoded bit rate                 */
                          Word16 clas,             /* i/o: frame classification                    */
                          const Word16 last_good,  /* i:   last good frame classification          */
                          Word16 * synth,          /* i/o: synthesized speech                      */
                          const Word16 * pitch,    /* i:   pitch values for each subframe          */
                          Word32 Lenr_q,           /* i:   transmitted energy for current frame    */
                          const Word16 prev_bfi,   /* i:   previous frame BFI                      */
                          Word16 Aq[],             /* i/o: LP filter coefs (can be modified if BR) */
                          Word16 * old_enr_LP,     /* i/o: LP filter E of last good G729EV_FEC_VOICED frame   Q4 */
                          Word16 * mem_tmp,        /* i/o: temporary synthesis memory              */
                          Word16 * exc_tmp,        /* i/o: temporary excitation                    */
                          Word32 Lenr_old,         /* i  : energy at the end of the last frame     */
                          Word16 * old_exc,        /* i/o: excitation buffer                       */
                          Word16 * mem_syn,        /* i/o: synthesis memory                        */
                          Word16 bfi_cnt           /* i  : Number of bad frame                     */
    )
{
  Word16    i, scale_flag;
  Word16    gain1, gain2, tmp, exp_enr, exp2, tmp2;
  Word32    Lenr1, Lenr2, L_tmp;
  Word16    enr_LP /*Q4 */ ;
  Word16    i_subfr, *p_Az;


  scale_flag = (Word16) 0;
  enr_LP = (Word16) 0;
  gain2 = (Word16) 0;
  gain1 = (Word16) 0;

#if(WMOPS)
  move16();
  move16();
  move16();
  move16();
  move32();
#endif
  if (Lenr_old == 0)
  {
    Lenr_old = (Word16) 1;
  }
   /*-----------------------------------------------------------------*
    * Find the synthesis filter impulse response on G729EV_FEC_VOICED     
    *-----------------------------------------------------------------*/

  IF(sub(clas, G729EV_FEC_V_TRANSITION) >= 0)
  {
    enr_LP = G729EV_FEC_enr_1_Az(Aq + 3 * (G729EV_G729_M + 1), G729EV_G729_L_SUBFR);  /*Q4 */
  }
#if (WMOPS)
  test();
  test();
#endif
  IF(sub(prev_bfi, G729EV_FEC_GOOD_FRAME) != 0  /* previous frame erased */
     && (sub(last_good, G729EV_FEC_SIN_ONSET) < 0 || sub(extrate, 40) > 0)  /* Do not scale if onset and energy doesnt sent by the encoder */
      )
  {
       /*-----------------------------------------------------------------*
        * Find the energy at the end of the frame 
        *-----------------------------------------------------------------*/
#if(WMOPS)
    move32();
#endif
    tmp = G729EV_FEC_energy(clas, synth, shr(add(pitch[3], G729EV_FEC_QPIT2), G729EV_FEC_SQPIT), &Lenr2, 1);
    IF(sub(clas, G729EV_FEC_VOICED) < 0)
    {
      /* Convert energy to Q0 */
      Lenr2 = L_mls(Lenr2, 26214);
      tmp = add(tmp, 6 + 1);
      Lenr2 = L_shr_r(Lenr2, tmp);
    }

    IF(sub(extrate, 40) <= 0)   /* < 16 kbps  use the nergy estimation from the decoder */
    {
      Lenr_q = Lenr2;
#if(WMOPS)
      move32();
      test();
#endif
      IF((sub(last_good, G729EV_FEC_V_TRANSITION) >= 0) && (sub(clas, G729EV_FEC_V_TRANSITION) >= 0)) /* G729EV_FEC_VOICED-G729EV_FEC_VOICED recovery */
      {
        IF(sub(enr_LP, *old_enr_LP) > 0)
        {

          /*enr_q /= enr_LP; */
          /*enr_q *= *old_enr_LP; */

          exp_enr = norm_l(Lenr_q);
          tmp = extract_h(L_shl(Lenr_q, exp_enr));

          exp2 = norm_s(enr_LP);
          tmp2 = shl(enr_LP, exp2);

          exp_enr = sub(exp2, exp_enr);

          IF(sub(tmp, tmp2) > 0)
          {
            tmp = shr(tmp, 1);
            exp_enr = add(exp_enr, 1);
          }

          tmp = div_s(tmp, tmp2);

          /* L_enr_q *= *old_enr_LP; */
          Lenr_q = L_shl(L_mult(tmp, *old_enr_LP), exp_enr);

          if (sub(bfi_cnt, 1) <= 0)
          {
            Lenr_q = L_shl(Lenr_q, 2);
          }

        }

        IF(sub(enr_LP, *old_enr_LP) < 0)
        {
          IF(L_sub(Lenr_q, L_shl(Lenr_old, 2)) > 0) /* Prevent energy to increase on G729EV_FEC_VOICED */
          {
            /*enr_q = 4*enr_old; */
            Lenr_q = L_shl(Lenr_old, 2);
          }
        }
        ELSE if   (L_sub(Lenr_q, Lenr_old) > 0)
        {
          /*enr_q = enr_old; */
          Lenr_q = Lenr_old;
#if(WMOPS)
          move32();
#endif
        }
      }
    }

    if (Lenr_q == 0)
    {
      Lenr_q = (Word32) 1;
#if(WMOPS)
      move32();
#endif
    }
    exp_enr = norm_l(Lenr_q);
    tmp = extract_h(L_shl(Lenr_q, exp_enr));

    exp2 = norm_l(Lenr2);
    tmp2 = extract_h(L_shl(Lenr2, exp2));

    exp2 = sub(exp_enr, exp2);  /* Denormalize and substract */


    IF(sub(tmp2, tmp) > 0)
    {
      tmp2 = shr(tmp2, 1);
      exp2 = add(exp2, 1);
    }

    tmp = div_s(tmp2, tmp);

    L_tmp = L_deposit_h(tmp);
    Isqrt_n(&L_tmp, &exp2);
    gain2 = round(L_shl(L_tmp, sub(exp2, 1)));  /* in Q14 */

    /*gain2 = (float)sqrt( enr_q / enr2 ); */


       /*-----------------------------------------------------------------*
        * Clipping of the smoothing gain at the frame end
        *-----------------------------------------------------------------*/

    IF((L_sub(Lenr_q, 1) <= 0)) /* Do not allow E increase if enr_q index==0 (lower end Q clipping) */
    {
      if (sub(gain2, 16384) > 0)
      {
        gain2 = (Word16) 16384; /* Gain modification clipping */
#if(WMOPS)
        move16();
#endif
      }
    }
    ELSE
    {
      if (sub(gain2, 19661) > 0)
      {
        gain2 = (Word16) 19661; /* Gain modification clipping */
#if(WMOPS)
        move16();
#endif
      }
    }

        /*-----------------------------------------------------------------*
        * Find the energy at the beginning of the frame to ensure smooth 
        * transition after erasure     
        *-----------------------------------------------------------------*/

    IF(sub(clas, G729EV_FEC_SIN_ONSET) == 0)  /* slow increase */
    {
      gain1 = mult_r(gain2, 16384);
      scale_flag = (Word16) 1;
#if(WMOPS)
      move16();
      move16();
#endif
    }
    ELSE if   (((sub(last_good, G729EV_FEC_V_TRANSITION) >= 0) && (sub(clas, G729EV_FEC_UNVOICED) == 0)))
    {
      gain1 = gain2;
      scale_flag = (Word16) 0;
#if(WMOPS)
      move16();
      move16();
#endif
    }
    ELSE
    {
#if(WMOPS)
      move32();
#endif
      /* Find the energy at the end of the frame */
      tmp = G729EV_FEC_energy(clas, synth, shr(add(pitch[0], G729EV_FEC_QPIT2), G729EV_FEC_SQPIT), &Lenr1, 0);
      IF(sub(clas, G729EV_FEC_VOICED) < 0)
      {
        /* Convert energy to Q0 */
        Lenr1 = L_mls(Lenr1, 26214);
        tmp = add(tmp, 6 + 1);
        Lenr1 = L_shr_r(Lenr1, tmp);
      }

      /* gain1 = (float)sqrt( *L_enr_old / L_enr1 ); */
      exp_enr = norm_l(Lenr_old);
      tmp = extract_h(L_shl(Lenr_old, exp_enr));
      exp2 = norm_l(Lenr1);
      tmp2 = extract_h(L_shl(Lenr1, exp2));

      exp2 = sub(exp_enr, exp2);  /* Denormalize and substract */
      IF(sub(tmp2, tmp) > 0)
      {
        tmp2 = shr(tmp2, 1);
        exp2 = add(exp2, 1);
      }

      tmp = div_s(tmp2, tmp);

      /* exp_enr = sub(exp2, exp_enr); */
      L_tmp = L_deposit_h(tmp);
      Isqrt_n(&L_tmp, &exp2);
      gain1 = round(L_shl(L_tmp, sub(exp2, 1)));  /* in Q14 */
#if(WMOPS)
      move32();
      move16();
      move16();
#endif
      if (sub(gain1, 19661) > 0)
      {
        /*gain1 = 1.2f; */
        gain1 = (Word16) 19661; /* Gain modification clipping   */
#if(WMOPS)
        move16();
        test();
#endif
      }
      IF((sub(clas, G729EV_FEC_ONSET) == 0) && (sub(gain1, gain2) > 0)) /* Prevent a catastrophy in case of offset followed by G729EV_FEC_ONSET */
      {
#if(WMOPS)
        move16();
#endif
        gain1 = gain2;
      }
      scale_flag = (Word16) 1;
    }

  }

   /*-----------------------------------------------------------------*
    * Smooth the energy evolution by exponentially evolving from 
    * gain1 to gain2        
    *-----------------------------------------------------------------*/

  IF(scale_flag != 0)
  {
    /*gain2 *= ( 1.0f - G729EV_FEC_AGC ); */
    gain2 = mult_r(gain2, (Word16) (32768 - G729EV_FEC_AGC));

    FOR(i = 0; i < G729EV_MAIN_L_FRAME2; i++)
    {
      /*gain1 = gain1 * G729EV_FEC_AGC + gain2; */
      gain1 = mac_r(L_shl(gain2, 16), gain1, G729EV_FEC_AGC); /* in Q14 */

      /*exc_tmp[i] *= gain1; */
      exc_tmp[i] = round(L_shl(L_mult(exc_tmp[i], gain1), 1));
#if(WMOPS)
      move16();
#endif
    }

    /* Update excitation memory with new excitation */
    G729EV_G729_Copy(&exc_tmp[G729EV_MAIN_L_FRAME2 - (G729EV_G729_PIT_MAX + G729EV_G729_L_INTERPOL)], old_exc,
                     G729EV_G729_PIT_MAX + G729EV_G729_L_INTERPOL);
  }
    /*-----------------------------------------------------------------*
    * Update the LP filter energy for G729EV_FEC_VOICED frames
    *-----------------------------------------------------------------*/
  if (sub(clas, G729EV_FEC_V_TRANSITION) >= 0)
  {
    *old_enr_LP = enr_LP;       /* Update */
#if(WMOPS)
    move16();
#endif
  }
    /*-----------------------------------------------------------------*
    * smoothing is done in excitation domain, so redo synthesis
    *-----------------------------------------------------------------*/