g729ev_main_filt.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 "stl.h"
#include "G729EV_G729_defines.h"
#include "G729EV_G729_ld8k.h"
#include "G729EV_MAIN_defines.h"
#include "G729EV_MAIN_filt.h"
#include "G729EV_MAIN_decod.h"
#include "G729EV_MAIN_OPER_32B.h"


/*--------------------------------------------------------------------------*
 *  Function  G729EV_MAIN_set_gamma()                                       *
 *  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~                                         *
 *  Set adaptive gamma parameters of lower-band postfilter                  *
 *--------------------------------------------------------------------------*/
void G729EV_MAIN_set_gamma(Word16 * output_lo,  /* (i)    lower-band synthesis prior to postfiltering */
                           Word16 * tab_Th,     /* (i/o)  median filter memory */
                           Word16 rate,         /* (i)    decoder bit rate */
                           Word16 * ga1_post,   /* (o)    gamma parameter */
                           Word16 * ga2_post    /* (o)    gamma parameter */
    )
{
  /* Variables declarations */
  Word32    L_temp;

  Word16    i, j;
  Word16    Th;

  /* set gammas */
  IF(sub(rate, 14000) >= 0)     /* >= 14 kbit/s */
  {
    *ga1_post = G729EV_G729_GAMMA1_PST12K;
    *ga2_post = G729EV_G729_GAMMA2_PST12K;
#if(WMOPS)
    move16();
    move16();
#endif
  }
  ELSE
  {
    IF(sub(rate, 12000) == 0)   /* == 12 kbit/s */
    {
      /* compute frame energy */
      L_temp = (Word32) 0;
#if(WMOPS)
      move32();
#endif
      FOR(i = 0; i < G729EV_MAIN_L_FRAME2; i++)
      {
        L_temp = L_mac(L_temp, output_lo[i], output_lo[i]);
      }

      /* compute Th */
      L_temp = L_shl(L_temp, 16);
      Th = extract_h(L_temp);

      /* smooth Th */
      j = sub(G729EV_MAIN_NMAX, 1);
      FOR(i = 0; i < j; i++)
      {
        tab_Th[i] = tab_Th[i + 1];
#if(WMOPS)
        move16();
#endif
      }
      tab_Th[j] = Th;
#if(WMOPS)
      move16();
#endif
      Th = G729EV_MAIN_gmed_n(tab_Th, G729EV_MAIN_NMAX);

      /* set gamma = Th * gamma_12k + (1-Th)*gamma_8k */
      L_temp = L_mult(Th, G729EV_G729_GAMMA1_PST12K);
      L_temp = L_mac(L_temp, sub(MAX_16, Th), G729EV_G729_GAMMA1_PST);
      *ga1_post = round(L_temp);

      L_temp = L_mult(Th, G729EV_G729_GAMMA2_PST12K);
      L_temp = L_mac(L_temp, sub(MAX_16, Th), G729EV_G729_GAMMA2_PST);
      *ga2_post = round(L_temp);
    }
    ELSE                        /* == 8 kbit/s */
    {
      /* at 8 kbit/s use gammas from G729 */
      *ga1_post = G729EV_G729_GAMMA1_PST;
      *ga2_post = G729EV_G729_GAMMA2_PST;
#if(WMOPS)
      move16();
      move16();
#endif
    }
  }


}


/*--------------------------------------------------------------------------*
 *  Function  G729EV_MAIN_gmed_n()                                          *
 *  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~                                            *
 *  Median filter for sequence of odd length                                *
 *--------------------------------------------------------------------------*/
/*  */
Word16 G729EV_MAIN_gmed_n(      /* (o) median value  */
                           Word16 ind[],  /* (i) Current and past values */
                           Word16 n       /* (i) number of values (valid for an odd number of gains <= G729EV_MAIN_NMAX) */
    )
{
  Word16    tmp[G729EV_MAIN_NMAX];
  Word16    tmp2[G729EV_MAIN_NMAX];

  Word16    i, j, ix;
  Word16    max;
  Word16    medianIndex;


  ix = (Word16) 0;
#if(WMOPS)
  move16();
#endif

  FOR(i = 0; i < n; i++)
  {
    tmp2[i] = ind[i];
#if(WMOPS)
    move16();
#endif
  }

  FOR(i = 0; i < n; i++)
  {
    max = (Word16) - 1;
#if(WMOPS)
    move16();
#endif
    FOR(j = 0; j < n; j++)
    {
      if (sub(tmp2[j], max) >= 0)
      {
        max = tmp2[j];
        ix = j;
#if(WMOPS)
        move16();
        move16();
#endif
      }
    }
    tmp2[ix] = (Word16) - 1;
    tmp[i] = ix;
#if(WMOPS)
    move16();
    move16();
#endif
  }

  medianIndex = tmp[shr(n, 1)]; /* account for complex addressing */
#if(WMOPS)
  move16();
#endif
  return (ind[medianIndex]);
}


/*--------------------------------------------------------------------------*
 *  Function  G729EV_MAIN_weighting_filter()                                *
 *  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~                                            *
 *  Weighting filter of lower-band difference signal including an adaptive  *
 *  gain compensation                                                       *
 *--------------------------------------------------------------------------*/
void G729EV_MAIN_weighting_filter(Word16 * Az,        /* (i)   LPC coefficients from CELP local decoder  */
                                  Word16 * mem_Wz_in, /* (i)   memory of input  */
                                  Word16 * mem_wsp,   /* (i)   memory of output  */
                                  Word16 * diff       /* (i/o) difference signal before and after weighting */
    )
{
  Word32    L_temp, L_num, L_den;

  Word16    wsp[G729EV_MAIN_L_FRAME2];
  Word16    Ap1[G729EV_G729_MP1];
  Word16    Ap2[G729EV_G729_MP1];
  Word16    Wz_in_buffer[G729EV_MAIN_L_FRAME2 + G729EV_G729_M];

  Word16   *Wz_in;
  Word16   *ptr_Az;

  Word16    i_subfr, i, j, end_loop;
  Word16    fac;
  Word16    e_den, frac_den, e_num, frac_num, e_fac;

  /* set buffer for W(z) */
  Wz_in = Wz_in_buffer + G729EV_G729_M;
#if(WMOPS)
  move16();
#endif
  G729EV_G729_Copy(mem_Wz_in, &Wz_in[-G729EV_G729_M], G729EV_G729_M);
  G729EV_G729_Copy(diff, Wz_in, G729EV_MAIN_L_FRAME2);
  G729EV_G729_Copy(&diff[(G729EV_MAIN_L_FRAME2) - G729EV_G729_M], mem_Wz_in, G729EV_G729_M);

  /* apply W(z)= fac*A(z/gamma1)/A(z/gamma2) */
  ptr_Az = Az;
  i_subfr = (Word16) 0;
#if(WMOPS)
  move16();
  move16();
#endif
  FOR(i = 0; i < 4; i++)
  {
    /* weight A(z) */
    G729EV_G729_Weight_Az(ptr_Az, G729EV_MAIN_GAMMA1, G729EV_G729_M, Ap1);
    G729EV_G729_Weight_Az(ptr_Az, G729EV_MAIN_GAMMA2, G729EV_G729_M, Ap2);

    /* compute gain  */
    L_den = L_deposit_h(shr(Ap1[0], 1));  /* (Word32)Q12>>1 -> Q27 = 1^27 */
    L_num = L_deposit_h(shr(Ap2[0], 1));  /* (Word32)Q12>>1 -> Q27 = 1^27 */
    fac = (Word16) - 16384;     /* Q13 */
#if(WMOPS)
    move16();
#endif
    FOR(j = 1; j <= G729EV_G729_M; j++)
    {
      /*                     Q12 x Q13<<1 -> Q26 */
      L_den = L_mac(L_den, Ap1[j], fac);  /* den += Ap1[j] << 14 */
      L_num = L_mac(L_num, Ap2[j], fac);  /* num += Ap2[j] << 14 */
      fac = negate(fac);
    }

    /* decompose L_den into exponent (e_den) and fraction (frac_den) */
    if (L_den < 0)
    {
      L_den = L_negate(L_den);  /* force den > 0 (needed by div_s) */
    }
    if (L_den == 0)
    {
      L_den = (Word32) 1;
#if(WMOPS)
      move32();
#endif
    }
    e_den = norm_l(L_den);
    frac_den = extract_h(L_shl(L_den, e_den));

    /* decompose L_num into exponent (e_den) and fraction (frac_den) */
    if (L_num < 0)
    {
      L_num = L_negate(L_num);
    }
    if (L_num == 0)
    {
      L_num = (Word32) 1;
#if(WMOPS)
      move32();
#endif
    }
    e_num = norm_l(L_num);
    frac_num = extract_h(L_shl(L_num, e_num));

    /* compute fac = div_s(frac_num, frac_den) * exponent */
    IF(sub(frac_num, frac_den) > 0)
    {
      frac_num = shr(frac_num, 1);
      e_num = sub(e_num, 1);
    }
    fac = div_s(frac_num, frac_den);

    e_fac = sub(e_num, e_den);
    e_fac = add(e_fac, 2);      /* shift by 2 ---> Q13 */
    fac = shr(fac, e_fac);      /* Q13 */

    /* filter by A(z/gamma) * 1/A(z/gamma2) */
    G729EV_G729_Residu(Ap1, &Wz_in[i_subfr], &wsp[i_subfr], G729EV_G729_L_SUBFR);
    G729EV_G729_Syn_filt(Ap2, &wsp[i_subfr], &wsp[i_subfr], G729EV_G729_L_SUBFR, mem_wsp, 0);
    FOR(j = 0; j < G729EV_G729_M; j++)
    {
#if(WMOPS)
      move16();
#endif
      mem_wsp[j] = wsp[i_subfr + G729EV_G729_L_SUBFR - G729EV_G729_M + j];
    }

    /* scale */
    end_loop = add(i_subfr, G729EV_G729_L_SUBFR);
    FOR(j = i_subfr; j < end_loop; j++)
    {
      /* wsp[j] *= fac; */
      L_temp = L_mult(wsp[j], fac); /* Q14 x Q13 <<1 = Q28 */
      L_temp = L_shl(L_temp, 2);  /* Q30 */
      wsp[j] = round(L_temp);   /* Q14 */
#if(WMOPS)
      move16();
#endif
    }

    ptr_Az += G729EV_G729_MP1;
    i_subfr += G729EV_G729_L_SUBFR;
  }
  G729EV_G729_Copy(wsp, diff, G729EV_MAIN_L_FRAME2);
}


/*--------------------------------------------------------------------------*
 *  Function  G729EV_MAIN_inverse_weighting_filter()                        *
 *  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~                          *
 *  Inverse weighting filter of lower-band difference signal including      *
 * an adaptive gain compensation                                            *
 *--------------------------------------------------------------------------*/
void G729EV_MAIN_inverse_weighting_filter(Word16 * Az,            /* (i)   LPC coefficients from CELP local decoder  */
                                          Word16 * mem_invWz_in,  /* (i)   memory of input  */
                                          Word16 * mem_invwsp,    /* (i)   memory of output  */
                                          Word16 * diff_q         /* (i/o) difference signal before and after weighting */
    )
{
  Word32    L_temp, L_num, L_den;

  Word16    invWz_in_buffer[G729EV_MAIN_L_FRAME2 + G729EV_G729_M];
  Word16    wsp[G729EV_MAIN_L_FRAME2];
  Word16    Ap1[G729EV_G729_MP1];
  Word16    Ap2[G729EV_G729_MP1];

  Word16   *invWz_in, *ptr_Az;

  Word16    i_subfr, i, j, end_loop;
  Word16    fac;
  Word16    e_den, frac_den, e_num, frac_num, e_fac;

  /* set buffer for W(z) */
  invWz_in = invWz_in_buffer + G729EV_G729_M;
#if(WMOPS)
  move16();
#endif
  G729EV_G729_Copy(mem_invWz_in, &invWz_in[-G729EV_G729_M], G729EV_G729_M);
  G729EV_G729_Copy(diff_q, invWz_in, G729EV_MAIN_L_FRAME2);
  G729EV_G729_Copy(&diff_q[(G729EV_MAIN_L_FRAME2) - G729EV_G729_M], mem_invWz_in, G729EV_G729_M);

  /* apply W(z)= fac*A(z/gamma2)/A(z/gamma1) */
  ptr_Az = Az;
  i_subfr = (Word16) 0;
#if(WMOPS)
  move16();
  move16();
#endif
  FOR(i = 0; i < 4; i++)
  {
    /* weight A(z) */
    G729EV_G729_Weight_Az(ptr_Az, G729EV_MAIN_GAMMA1, G729EV_G729_M, Ap1);
    G729EV_G729_Weight_Az(ptr_Az, G729EV_MAIN_GAMMA2, G729EV_G729_M, Ap2);

    /* compute gain */
    L_den = L_deposit_h(shr(Ap2[0], 1));  /* (Word32)Q12>>1 -> Q27 */
    L_num = L_deposit_h(shr(Ap1[0], 1));  /* (Word32)Q12>>1 -> Q27 */
    fac = (Word16) - 16384;     /* Q13 */
#if(WMOPS)
    move16();
#endif
    FOR(j = 1; j <= G729EV_G729_M; j++)
    {
      /*                     Q12 x Q13<<1 -> Q26 */
      L_den = L_mac(L_den, Ap2[j], fac);  /* den += Ap1[j] << 14 */
      L_num = L_mac(L_num, Ap1[j], fac);  /* num += Ap2[j] << 14 */