g729ev_celp2s_decod.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.

#if (WMOPS)
        move16();
#endif
      }
      *ptr_t2++ = t0;
#if (WMOPS)
      move16();
#endif
      pitch_buf[pDecStat->i_subfr_cnt] = shl(t0, G729EV_FEC_SQPIT);
#if (WMOPS)
      move16();
#endif
      IF(sub(clas, G729EV_FEC_UV_TRANSITION) >= 0)
      {
        pDecStat->fpitch[0] = pDecStat->fpitch[1];
        pDecStat->fpitch[1] = add(shl(t0, G729EV_FEC_SQPIT), mult_r(shl(t0_frac, G729EV_FEC_SQPIT), 10922));
#if (WMOPS)
        move16();
        move16();
#endif
      }
    /*-------------------------------------------------*
    * - Find the adaptive codebook vector.            *
    *-------------------------------------------------*/

      G729EV_G729_Pred_lt_3(&exc[i_subfr], t0, t0_frac, G729EV_G729_L_SUBFR);

    /*-------------------------------------------------------*
    * - Decode innovative codebook.                         *
    *-------------------------------------------------------*/

      G729EV_G729_Decod_ACELP(prm[1], prm[0], code);
      prm += 2;


      j = shl(pDecStat->sharp, 1);  /* From Q14 to Q15 */
      IF(sub(t0, G729EV_G729_L_SUBFR) < 0)
      {
        ptr = code + t0;
        FOR(i = t0; i < G729EV_G729_L_SUBFR; i++)
        {
          *ptr++ = add(code[i], mult(code[sub(i, t0)], j));
#if (WMOPS)
          move16();
#endif
        }
      }

  /*-------------------------------------------------*
    * - Decode pitch and codebook gains.              *
    *-------------------------------------------------*/

      index = *prm++;           /* index of energy VQ */

#if (WMOPS)
      move16();
#endif



      G729EV_G729_Dec_gain(index, code, G729EV_G729_L_SUBFR, 0, &pDecStat->gain_pitch, &pDecStat->gain_code,
                           pDecStat->past_qua_en);

      voice_fac = G729EV_FEC_voice_factor(exc + i_subfr, pDecStat->gain_pitch, code, pDecStat->gain_code);

      sp = extract_l(L_shr(L_add(voice_fac, 32767), 1));
      sp = mult_r(sp, G729EV_CELP2S_SP);

  /*-------------------------------------------------------*
  * - Decode Second innovative codebook.                  *
  *-------------------------------------------------------*/
      IF(sub(pDecStat->rate, 12000) >= 0)
      {
        G729EV_CELP2S_Decod_ACELP(prm2[1], prm2[0], sp, code_enha);
        prm2 += 2;
      }

  /*-------------------------------------------------------------*
    * - Update pitch sharpening "sharp" with quantized gain_pitch *
    *-------------------------------------------------------------*/

      pDecStat->sharp = pDecStat->gain_pitch;
#if (WMOPS)
      move16();
#endif

      if (sub(pDecStat->sharp, G729EV_G729_SHARPMAX) > 0)
      {
        pDecStat->sharp = G729EV_G729_SHARPMAX;
#if (WMOPS)
        move16();
#endif
      }
      if (sub(pDecStat->sharp, G729EV_G729_SHARPMIN) < 0)
      {
        pDecStat->sharp = G729EV_G729_SHARPMIN;
#if (WMOPS)
        move16();
#endif
      }

   /*-------------------------------------------------------*
    * - Find the total excitation.                          *
    * - Find synthesis speech corresponding to exc[].       *
    *-------------------------------------------------------*/
      g_p = G729EV_G729_TamFer(pDecStat, pDecStat->gain_pitch,  /*gain */
                               t0); /*integer part of the pitch */
      g_c = pDecStat->gain_code;
#if (WMOPS)
      move16();
#endif

      /* i0_2sub = 2*SubFrNum + i0 */

      nb_celp_param->t0[i0_2sub] = t0;
      nb_celp_param->t0_frac[i0_2sub] = t0_frac;
#if (WMOPS)
      move16();
      move16();
#endif


      nb_celp_param->power_ltp[i0_2sub] = 0;
#if (WMOPS)
      move16();
#endif

      ptr = exc + i_subfr;
      L_temp2 = nb_celp_param->power_ltp[i0_2sub];
#if (WMOPS)
      move16();
      move32();
#endif
      FOR(i = 0; i < G729EV_G729_L_SUBFR; i++)
      {
        temp = mult(g_p, exc[i + i_subfr]);
        L_temp2 = L_mac0(L_temp2, temp, temp);

        /* exc[i] = g_p*exc[i] + g_c*code[i]; */
        /* exc[i]  in Q1   g_p in Q14         */
        /* code[i] in Q13  g_code in Q1       */


        L_temp = L_mult(code[i], g_c);  /* Q13 * Q1 -> Q15 */
        L_temp = L_shl(L_temp, 1);  /* Q15 -> Q_N+15  */
        L_temp = L_mac(L_temp, exc[i + i_subfr], g_p);  /* Q_N * Q14 -> Q_N+15 */
        L_temp = L_shl(L_temp, 1);  /* Q_N+15 -> Q_N+16  */
        *ptr++ = round(L_temp);
#if (WMOPS)
        move16();
#endif

      }

      nb_celp_param->power_ltp[i0_2sub] = L_temp2;
#if (WMOPS)
      move32();
#endif



      IF(sub(pDecStat->rate, 12000) >= 0)
      {
#if (WMOPS)
        move16();
#endif
        index = *prm2++;


        nb_celp_param->power_fix[i0_2sub] = 0;
#if (WMOPS)
        move16();
#endif


        /* decode gain (optimized version: table lookup) */
        g_c_enha = G729EV_CELP2S_dec_gain_Stage2(g_c, index, i0_2sub);

        /* Compute excitation for with two inovative codebook         */
        /* exc2[i+i_subfr] = g_c_enha * code_enha[i] + exc[i+i_subfr] */
        /* exc[i]  in Q1                                              */
        /* code_enha[i] in Q13  gain_code_enha in Q1                  */

        ptr = exc2 + i_subfr;
        L_temp2 = nb_celp_param->power_fix[i0_2sub];
#if (WMOPS)
        move32();
#endif
        FOR(i = 0; i < G729EV_G729_L_SUBFR; i++)
        {

          temp = add(mult(g_c, code[i]), mult(g_c_enha, code_enha[i]));
          L_temp2 = L_mac0(L_temp2, temp, temp);

          L_temp = L_mult(code_enha[i], g_c_enha);  /* Q13 * Q1 -> Q15 */
          L_temp = L_shl(L_temp, 1);  /* Q15 -> Q_N+15   */
          L_temp = L_mac(L_temp, exc[i + i_subfr], 16384);  /* Q_N * Q_14 -> Q_N+15 */
          L_temp = L_shl(L_temp, 1);  /* Q_N+15 -> Q_N+16 */
          *ptr++ = round(L_temp);
#if (WMOPS)
          move16();
#endif
        }

        nb_celp_param->power_fix[i0_2sub] = L_temp2;
#if (WMOPS)
        move32();
#endif

      }

      tmp16 = add(pDecStat->i_subfr_cnt, 1);
      tmp16 = i_mult(tmp16, 3277);
      pDecStat->lp_gainp = add(pDecStat->lp_gainp, mult_r(tmp16, g_p));
      pDecStat->lp_gainc = add(pDecStat->lp_gainc, mult_r(tmp16, shl(g_c, 2)));
      pDecStat->tilt_code = extract_l(L_shr(L_add(voice_fac, 32767), 2));
      pDecStat->i_subfr_cnt = add(pDecStat->i_subfr_cnt, 1);

      pA_t += G729EV_G729_MP1;  /* interpolated LPC parameters for next subframe */

      i0_2sub = add(i0_2sub, 1);  /* i0++ */
    }
  }

  /*------------*
   *  For G729b
   *-----------*/
  IF(bfi == 0)
  {
    L_temp = 0L;
    FOR(i = 0; i < G729EV_G729_L_FRAME; i++)
    {
      L_temp = L_mac(L_temp, exc[i], exc[i]);
    }                           /* may overflow => last level of SID quantizer */
    pDecStat->sh_sid_sav = norm_l(L_temp);
    pDecStat->sid_sav = round(L_shl(L_temp, pDecStat->sh_sid_sav));
    pDecStat->sh_sid_sav = sub(16, pDecStat->sh_sid_sav);
  }


 /*--------------------------------------------------*
  * Update signal for next frame.                    *
  * -> shift to the left by L_FRAME  exc[]           *
  *--------------------------------------------------*/

  G729EV_G729_Copy(&old_exc[G729EV_G729_L_FRAME], &pDecStat->old_exc[0], G729EV_G729_PIT_MAX + G729EV_G729_L_INTERPOL);


  G729EV_G729_Copy(exc, coreExc, G729EV_G729_L_FRAME);
  G729EV_G729_Copy(exc2, extExc, G729EV_G729_L_FRAME);
  G729EV_G729_Copy(A_t_fwd, BfAq, 2 * G729EV_G729_MP1);

  /* for G729b */
  pDecStat->past_ftyp = ftyp;
#if (WMOPS)
  move16();
#endif

  return;
}





/*-----------------------------------------------------------*
 *  Function  G729EV_CELP2S_Decod_pos_sig()                   *
 *  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~                    *
 *   Decode positions and signs of the 4 tri-pulse patterns  *
 *-----------------------------------------------------------*/
void G729EV_CELP2S_Decod_pos_sig(Word16 index,  /* (i) : Positions of the 4 pattern */
                                 Word16 sign,   /* (i) : Signs of the 4 pattern */
                                 Word16 pos[],  /* (o) : Decoded positions */
                                 Word16 si[]    /* (o) : Decoded signs */
    )
{
  Word16    i, j;

  /* Decode the positions */

#ifdef WMOPS
  logic16();
  move16();
#endif
  i = index & (Word16) 7;
  pos[0] = add(i, shl(i, 2));   /* pos0 =i*5 */
  index = shr(index, 3);

#ifdef WMOPS
  logic16();
  move16();
#endif
  i = index & (Word16) 7;
  i = add(i, shl(i, 2));        /* pos1 =i*5+1 */
  pos[1] = add(i, 1);
  index = shr(index, 3);

#ifdef WMOPS
  logic16();
  move16();
#endif
  i = index & (Word16) 7;
  i = add(i, shl(i, 2));        /* pos2 =i*5+1 */
  pos[2] = add(i, 2);
  index = shr(index, 3);

#ifdef WMOPS
  logic16();
  logic16();
  move16();
#endif
  j = index & (Word16) 1;
  index = shr(index, 1);
  i = index & (Word16) 7;
  i = add(i, shl(i, 2));        /* pos3 =i*5+3+j */
  i = add(i, 3);
  pos[3] = add(i, j);


  /* Decode the signs */

  FOR(j = 0; j < 4; j++)
  {
#ifdef WMOPS
    logic16();
    move16();
#endif
    i = sign & (Word16) 1;
    si[j] = i;
    sign = shr(sign, 1);
  }

  return;
}



/*-----------------------------------------------------------*
 *  Function  G729EV_CELP2S_Decod_ACELP()                    *
 *  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~                    *
 *   Algebraic codebook decoder.                             *
 *-----------------------------------------------------------*/

void G729EV_CELP2S_Decod_ACELP(Word16 sign,   /* (i)     : Signs of 4 patterns                       */
                               Word16 index,  /* (i)     : Positions of the 4 pattern centres        */
                               Word16 sp,     /* (i)     : Amplitude of the side pulses.             */
                               Word16 cod[]   /* (o) Q13 : algebraic (fixed) codebook excitation     */
    )
{
  Word16    pos[4];
  Word16    si[4];

  /* Decode the positions and signs */
  G729EV_CELP2S_Decod_pos_sig(index, sign, pos, si);

  /* Put the tri-pulse patterns */
  G729EV_CELP2S_Put4Patterns(pos, si, sp, cod);

  return;
}