g729ev_main_envadaption.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 "G729EV_MAIN_defines.h"
#include "G729EV_MAIN_EnvAdaption.h"
#include "G729EV_MAIN_DSPFUNC.h"
#include "G729EV_MAIN_OPER_32B.h"

/*--------------------------------------------------------------------------*
 *  Function  get_Energy()                                                  *
 *  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~                                   *
 *  Compute subframe energy                                                 *
 *--------------------------------------------------------------------------*/
void G729EV_MAIN_get_Energy(Word16 * pSample, /* (i)   input samples */
                            Word32 * pELow,   /* (o)   energy (LSB) */
                            Word16 * pEHigh   /* (o)   energy (MSB) */
    )
{
  Word16    i;

  Overflow = 0;
#ifdef WMOPS
  move16();
#endif
  FOR(i = 0; i < G729EV_MAIN_PRE_SUBFRAME; i++)
  {
    *pELow = L_macNs(*pELow, pSample[i], pSample[i]);
    if (Overflow != 0)
      *pEHigh = add(*pEHigh, 1);
    if (Overflow != 0)
      *pELow = L_and(*pELow, 0x7fffffff);
    if (Overflow != 0)
    {
      Overflow = 0;
#ifdef WMOPS
      move16();
#endif
    }
  }
}

/*--------------------------------------------------------------------------*
 *  Function  G729EV_MAIN_getV()                                            *
 *  ~~~~~~~~~~~~~~~~~~~~~~~~~~                 ~                            *
 *  Compute attenuation factor e_num/e_den                                  *
 *--------------------------------------------------------------------------*/
Word16 G729EV_MAIN_getV(Word32 e_num, /* (i)   numerator */
                        Word32 e_den  /* (i)   denominator */
    )
{
  Word16    v;
  Word16    n1, n2, d, n;
  Word32    v32, e_den32;
  Word16    e_num16;

  n1 = norm_l(e_num);
  n2 = norm_l(e_den);
  e_den32 = L_shl(e_den, sub(n2, 1));
  e_num16 = extract_l(L_shl(e_num, sub(n1, 16)));
  d = div_l(e_den32, e_num16);
  v32 = Inv_sqrt(d);
  n = add(sub(n2, n1), 14);
  v = extract_l(L_shr(v32, sub(23, shr(n, 1))));  /* Q30->Q7 */
  IF(L_and(n, 1) != 0)          /* (n%2 !=0) */
  {
    v32 = L_mult(v, 0x5a82);    /* (REAL)v32*1.41; */
    v = shl(extract_h(v32), 1); /* extract_h(v32*4); */
  }
  v = i_mult(v, 0x100);
  return (v);
}

/*--------------------------------------------------------------------------*
 *  Function  G729EV_MAIN_smooth()                                          *
 *  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~                                            *
 *  Smooth gain                                                             *
 *--------------------------------------------------------------------------*/
Word16 G729EV_MAIN_smooth(Word16 lastVal, /* (i)   smoothing filter memory */
                          Word16 newVal   /* (i)   input gain */
    )
{
  Word32    acc;

  /* return lastVal*0.85 + newVal*0.15 */
  acc = L_mult(lastVal, 0x6ccd);
  acc = L_mac(acc, newVal, 0x1333);
  return round(acc);
}

/*--------------------------------------------------------------------------*
 *  Function  G729EV_MAIN_envAdapt()                                        *
 *  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~                                          *
 *  Reduce pre/postecho in lower and higher band                            *
 *  Add CELP and TDAC synthesis in lower-band                               *
 *--------------------------------------------------------------------------*/
void G729EV_MAIN_envAdapt(Word16 * sOut_low,      /* (o)   output samples lowband */
                          Word16 * sBasic_low,    /* (i)   12k layer contribution (lowband)  */
                          Word16 * sTdacAdd_low,  /* (i)   TDAC layer add-on for lowand  */
                          Word16 * vmlold,        /* (i)   needed for lowband gain smoothing  */
                          Word16 * sOut_hi,       /* (o)   output samples highband */
                          Word16 * sBasic_hi,     /* (i)   14k layer contribution (highband) */
                          Word16 * sTdacInc_hi,   /* (i)   highband signal TDBWE combinded with TDAC */
                          Word16 * vmhold,        /* (i)   needed for highband gain smoothing */
                          Word16 work,            /* (i)   if zero ->do not cancel echo (rate<=14000) */
                          Word16 begin_index_low, /* (i)   start index for false alarm zone in lower-band  */
                          Word16 end_index_low,   /* (i)   stop index for false alarm zone in lower-band */
                          Word16 begin_index_high,/* (i)   start index for false alarm zone in higher-band */
                          Word16 end_index_high   /* (i)   stop index for false alarm zone in higher-band */
    )
{
  Word16    i, j;
  Word16    vl, vh;
  Word16    vml[G729EV_MAIN_L_FRAME2];
  Word16    vmh[G729EV_MAIN_L_FRAME2];
  Word16    sBasicLow_tilt[G729EV_MAIN_L_FRAME2];
  Word16    sTdacAddLow_tilt[G729EV_MAIN_L_FRAME2];
  Word16   *sHelp1;
  Word16   *sHelp2;
  Word32    EsBasicLow;
  Word32    EsTdacAddLow;
  Word32    EsBasicHi;
  Word32    EsTdacIncHi;
  Word16    EsBasicLowHigh;
  Word16    EsTdacAddLowHigh;
  Word16    EsBasicHiHigh;
  Word16    EsTdacIncHiHigh;
  Word32    EsTdacIncHi081;
  Word16   *pvl;
  Word16   *pvh;
  Word16    Hi, Lo;

  /* apply tilt on lowband before comparing energies */
  sHelp1 = sBasic_low - 1;
  sHelp2 = sTdacAdd_low - 1;
#ifdef WMOPS
  move16();
  move16();
#endif
  FOR(j = 1; j < G729EV_MAIN_L_FRAME2; j++)
  {
    sBasicLow_tilt[j] = sub(sBasic_low[j], sHelp1[j]);
#ifdef WMOPS
    move16();
#endif
    sTdacAddLow_tilt[j] = sub(sTdacAdd_low[j], sHelp2[j]);
#ifdef WMOPS
    move16();
#endif
  }
  sBasicLow_tilt[0] = 0;
#ifdef WMOPS
  move16();
#endif
  sTdacAddLow_tilt[0] = 0;
#ifdef WMOPS
  move16();
#endif

  /* compare energies, get scale factors */
  FOR(j = 0; j < G729EV_MAIN_L_FRAME2; j = j + G729EV_MAIN_PRE_SUBFRAME)
  {


    IF(work)
    {
      /* get energies */
      EsBasicLow = 100;
      EsTdacAddLow = 100;
      EsBasicHi = 100;
      EsTdacIncHi = 100;
#ifdef WMOPS
      move32();
      move32();
      move32();
      move32();
#endif
      EsBasicLowHigh = 0;
      EsTdacAddLowHigh = 0;
      EsBasicHiHigh = 0;
      EsTdacIncHiHigh = 0;
#ifdef WMOPS
      move16();
      move16();
      move16();
      move16();
#endif
      Overflow = 0;
      Carry = 0;
#ifdef WMOPS
      move16();
      move16();
#endif


      G729EV_MAIN_get_Energy(&sBasicLow_tilt[j], &EsBasicLow, &EsBasicLowHigh);
      G729EV_MAIN_get_Energy(&sTdacAddLow_tilt[j], &EsTdacAddLow, &EsTdacAddLowHigh);
      G729EV_MAIN_get_Energy(&sBasic_hi[j], &EsBasicHi, &EsBasicHiHigh);
      G729EV_MAIN_get_Energy(&sTdacInc_hi[j], &EsTdacIncHi, &EsTdacIncHiHigh);

      /* if highpart of energy != zero, normalize */
      IF(add(EsBasicLowHigh, EsTdacAddLowHigh) != 0)
      {
        Word16    max16, v, i31mv;

        max16 = s_max(EsBasicLowHigh, EsTdacAddLowHigh);
        v = norm_l(max16);
        i31mv = sub(31, v);
        EsBasicLow = L_add(L_shl(EsBasicLowHigh, v), L_shr((EsBasicLow & 0x7fffffff), i31mv));
        EsTdacAddLow = L_add(L_shl(EsTdacAddLowHigh, v), L_shr((EsTdacAddLow & 0x7fffffff), i31mv));
      }
      IF(L_sub(EsBasicLow, EsTdacAddLow) >= 0)  /* if EsBasicLow>=EsTdacAddLow */
      {
        vl = 0x7fff;            /* vl=1 */
#ifdef WMOPS
        move16();
#endif
      }
      ELSE
      {
        vl = G729EV_MAIN_getV(EsBasicLow, EsTdacAddLow);
      }

      /* if highpart of energy != zero, normalize */
      IF(add(EsBasicHiHigh, EsTdacIncHiHigh) != 0)
      {
        Word16    max16, v, i31mv;

        max16 = s_max(EsBasicHiHigh, EsTdacIncHiHigh);
        v = norm_l(max16);
        i31mv = sub(31, v);
        EsBasicHi = L_add(L_shl(EsBasicHiHigh, v), L_shr((EsBasicHi & 0x7fffffff), i31mv));
        EsTdacIncHi = L_add(L_shl(EsTdacIncHiHigh, v), L_shr((EsTdacIncHi & 0x7fffffff), i31mv));
      }
      /* EsTdacIncHi081=EsTdacIncHi*0.81: */

      L_Extract(EsTdacIncHi, &Hi, &Lo);
      EsTdacIncHi081 = Mpy_32_16(Hi, Lo, 0x67ae);

      IF(L_sub(EsBasicHi, EsTdacIncHi081) >= 0)
      {
        vh = 0x7fff;            /* vh=1 */
#ifdef WMOPS
        move16();
#endif
      }
      ELSE
      {
        vh = G729EV_MAIN_getV(EsBasicHi, EsTdacIncHi);
      }

    }

    ELSE
    {
      vh = 0x7fff;              /* vh=1 */
      vl = 0x7fff;              /* vl=1 */
#ifdef WMOPS
      move16();
      move16();
#endif
    }

    pvl = &vml[j];
    pvh = &vmh[j];
#ifdef WMOPS
    move16();
    move16();
#endif

    FOR(i = 0; i < G729EV_MAIN_PRE_SUBFRAME; i++)
    {
      pvl[i] = vl;
      pvh[i] = vh;
#ifdef WMOPS
      move16();
      move16();
#endif
    }
  }

/* begin_index_low = 0; end_index_low = 159; no preecho supression */

  FOR(i = begin_index_low; i <= end_index_low; i++)
  {
    vml[i] = 0x7fff;
#ifdef WMOPS
    move16();
#endif
  }

  FOR(i = begin_index_high; i <= end_index_high; i++)
  {
    vmh[i] = 0x7fff;
#ifdef WMOPS
    move16();
#endif
  }


  /* EnvAdaption - smoothing of gains */
  vmh[0] = G729EV_MAIN_smooth(*vmhold, vmh[0]);
  vml[0] = G729EV_MAIN_smooth(*vmlold, vml[0]);
#ifdef WMOPS
  move16();
  move16();
#endif

  FOR(i = 1; i < (G729EV_MAIN_L_FRAME2); i++)
  {
    vmh[i] = G729EV_MAIN_smooth(vmh[i - 1], vmh[i]);
    vml[i] = G729EV_MAIN_smooth(vml[i - 1], vml[i]);
#ifdef WMOPS
    move16();
    move16();
#endif
  }


  /* update vmh vml memory */
  *vmlold = vml[(G729EV_MAIN_L_FRAME2) - 1];
  *vmhold = vmh[(G729EV_MAIN_L_FRAME2) - 1];
#ifdef WMOPS
  move16();
  move16();
#endif

  FOR(i = 0; i < G729EV_MAIN_L_FRAME2; i++)
  {
    sOut_low[i] = add(sBasic_low[i], mult_r(sTdacAdd_low[i], vml[i]));
    sOut_hi[i] = mult_r(sTdacInc_hi[i], vmh[i]);

#ifdef WMOPS
    move16();
    move16();
#endif
  }
}


/*--------------------------------------------------------------------------*
 *  Function  G729EV_MAIN_PreechoFalseAlarm()                               *
 *  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~                                          *
 *  Determine start/stop indices for false alarm zone in lower- and higher- *
 *  band                                                                    *
 *--------------------------------------------------------------------------*/
void G729EV_MAIN_PreechoFalseAlarm(Word16 * rec_sig,    /* (i)   reconstructed signal, output of the imdct transform */
                                   Word16 * imdct_mem,  /* (i)   memory of the imdct transform, used in the next frame */
                                   Word32 * max_prev,   /* (i/o) maximum energy in the previous reconstructed frame */
                                   Word16 * begin_ind,  /* (o)   starting index of the eventual false alarm zone */
                                   Word16 * end_ind     /* (o)   ending index of the eventual false alarm zone */
    )
{
  Word16    i, j;
  Word32    es_tdac[6];         /* 0..3: energy of the 4 subframes, 4..5: energy of the future subframes */
  Word32    min_es, max_es, max_rec = 0;
  Word16   *ptr;

  /*energy of low bands 4 present and 2 future sub-frames */
  FOR(i = 0; i < 6; i++)
  {
    es_tdac[i] = 100;
#ifdef WMOPS
    move32();
#endif
  }
  ptr = rec_sig;
#if(WMOPS)
  move16();
#endif
  FOR(j = 0; j < 4; j++)       /*4 present subframes */
  {
    FOR(i = 0; i < G729EV_MAIN_PRE_SUBFRAME; i++)
    {
      es_tdac[j] = L_mac0(es_tdac[j], *ptr, *ptr);
#ifdef WMOPS
      move32();
#endif
      ptr++;
    }
  }

  ptr = imdct_mem;
#if(WMOPS)
  move16();
#endif
  FOR(j = 4; j < 6; j++)       /*2 future subframes */
  {
    FOR(i = 0; i < G729EV_MAIN_PRE_SUBFRAME; i++)
    {
      es_tdac[j] = L_mac(es_tdac[j], *ptr, *ptr); /*including *=2 as the max of the synthesis window is sqrt(2) */
#ifdef WMOPS
      move32();
#endif
      ptr++;
    }
  }

  min_es = es_tdac[0];          /* for memorising the min energy */
  max_es = es_tdac[0];          /* for memorising the max energy */
  *begin_ind = 0;
#if(WMOPS)
  move32();
  move32();
  move16();
#endif

  FOR(i = 1; i < 6; i++)
  {
    if (L_sub(es_tdac[i], max_es) > 0)
    {
      max_es = es_tdac[i];      /* max energy low band, 4 present and 2 future subframes */
      *begin_ind = extract_l(L_mult0(i, G729EV_MAIN_PRE_SUBFRAME));
#ifdef WMOPS
      move32();
#endif
    }
    if (sub(i, 3) == 0)
    {
      max_rec = max_es;         /*save partial max result for the 4 present subframes */
#ifdef WMOPS
      move32();
#endif
    }

  }

  IF(L_sub(L_shr(*max_prev, 5), max_rec) >= 0)  /*post-echo situation, preecho false alarm detection desactivated */
  {
    *begin_ind = G729EV_MAIN_L_FRAME2;
    *end_ind = G729EV_MAIN_L_FRAME2 - 1;  /* begin > end --> nothing is done */
    *max_prev = max_rec;
#ifdef WMOPS
    move16();
    move16();
    move32();
#endif
  }
  ELSE
  {
    *max_prev = max_rec;
#ifdef WMOPS
    move32();
#endif
    FOR(i = 1; i < 4; i++)
    {
      if (L_sub(es_tdac[i], min_es) < 0)
      {
        min_es = es_tdac[i];    /* min energy low band, 4 present subframes only */
#ifdef WMOPS
        move32();
#endif
      }
    }
    IF(L_sub(L_shr(max_es, 4), min_es) < 0) /* no big energy change --> no preecho ->false alarm zone:the whole frame */
    {
      *begin_ind = 0;
      *end_ind = G729EV_MAIN_L_FRAME2 - 1;
#ifdef WMOPS
      move16();
      move16();
#endif
    }
    ELSE
    {
      *end_ind = add(*begin_ind, 2 * G729EV_MAIN_PRE_SUBFRAME - 1); /*length of the false alarm zone is 2 subframes */
      if (sub(*end_ind, G729EV_MAIN_L_FRAME2 - 1) > 0)
      {
        *end_ind = G729EV_MAIN_L_FRAME2 - 1;
#ifdef WMOPS
        move16();
#endif
      }
    }
  }
  return;
}