g729ev_main_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.

/* 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 "G729EV_MAIN_defines.h"
#include "G729EV_G729_defines.h"
#include "G729EV_G729_DecStat.h"
#include "G729EV_CELP2S_decod.h"
#include "G729EV_MAIN_filt.h"
#include "G729EV_MAIN_decod.h"
#include "G729EV_G729_ld8k.h"
#include "G729EV_G729_TAB_ld8k.h"
#include "G729EV_FEC_fer.h"
#include "G729EV_MAIN_EnvAdaption.h"
#include "G729EV_TDAC_decod.h"
#include "G729EV_TDAC_mdct.h"
#include "G729EV_TDAC_util.h"
#include "G729EV_MAIN_DSPFUNC.h"
#include "G729EV_MAIN_prm.h"
#include "G729EV_TDAC_post.h"
#include "G729EV_CELP2S_post.h"


/*--------------------------------------------------------------------------*
 *  Function  G729EV_MAIN_InitDecoder()                                     *
 *  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~                                     *
 *  Decoder Initializations                                                 *
 *--------------------------------------------------------------------------*/

void G729EV_MAIN_InitDecoder(DECSTATMAIN * decstat, /* (o)  decoder states variables    */
                             Word16 f8,             /* (i)  8kHz sampled input flag     */
                             Word16 g729b_bst,      /* (i)  G.729 bistream mode flag    */
                             Word16 low_delay)      /* (i)  Low-delay mode flag         */
{
  Word16    i;

  IF(decstat == NULL)
  {
    exit(-1);
  }

  memset(decstat, 0, sizeof(*decstat));

  /* set previous bad frame indicator */
  decstat->prev_bfi = (Word16) 0;
#if(WMOPS)
  move16();
#endif

  /* set the flag for 8kHz sampled output */
  decstat->f8 = f8;
#if (WMOPS)
  move16();
#endif

  /* set the flag for g729 bitstream mode */
  decstat->g729b_bst = g729b_bst;
#if(WMOPS)
  move16();
#endif

  decstat->low_delay = low_delay;
#if(WMOPS)
  move16();
#endif

  /* initialize QMF filterbank */
  G729EV_MAIN_initQMF_syn(&decstat->qmf_syn);

  /* initialize CELP decoder */
  G729EV_CELP2S_InitDecoder(&decstat->decStG729, g729b_bst);

  /* initialize memories for MDCT computation */
  G729EV_G729_Set_zero(decstat->mem_mdct_hi, G729EV_MAIN_L_FRAME2);
  G729EV_G729_Set_zero(decstat->mem_inv_mdct_hi, G729EV_MAIN_L_FRAME2);
  G729EV_G729_Set_zero(decstat->mem_inv_mdct_lo, G729EV_MAIN_L_FRAME2);

  G729EV_G729_Set_zero(decstat->sTdbweOld, G729EV_MAIN_L_FRAME2);

  decstat->vmhold = (Word16) 0x7fff;  /* Q.15, 1.0 */
  decstat->vmlold = (Word16) 0x7fff;  /* Q.15, 1.0 */
#if(WMOPS)
  move16();
  move16();
#endif

  /* initialize TDBWE decoder */
  G729EV_TDBWE_decoder_init(&decstat->tdbwe);
  IF(decstat->low_delay > 0) G729EV_MAIN_init_lp3k(&decstat->mem_lp3k);

  /* initialize memory of previous CELP-decoded frame (for difference computation in lower band) */
  G729EV_G729_Set_zero(decstat->old_celp_output, G729EV_MAIN_L_FRAME2);

  /* postfiltering */
  G729EV_G729_Set_zero(decstat->mem_pf_in, G729EV_G729_M_LPC);
  G729EV_CELP2S_init_post_filter(&decstat->mem_pf);
  G729EV_G729_Set_zero(decstat->mem_Az, 4 * G729EV_G729_MP1);

  FOR(i = 0; i < (4 * G729EV_G729_MP1); i += G729EV_G729_MP1)
  {
    decstat->mem_Az[i] = (Word16) 4096;
#if(WMOPS)
    move16();
#endif
  }
  FOR(i = 0; i < 4; i++)
  {
    decstat->mem_t0[i] = (Word16) 60;
#if(WMOPS)
    move16();
#endif
  }

  /* post processing */
  IF(low_delay == 0) decstat->mem_postflag = (Word16) 0;
  ELSE decstat->mem_postflag = (Word16) 1;
#if(WMOPS)
  move16();
#endif
  G729EV_MAIN_init_iir2(&decstat->mem_postpro);

  /* perceptual weighting filter of lower band difference signal */
  G729EV_G729_Set_zero(decstat->mem_invWz_in, G729EV_G729_M);
  G729EV_G729_Set_zero(decstat->mem_invwsp, G729EV_G729_M);

  /* bitrate switching initialization */
  decstat->count_rcv = G729EV_MAIN_COUNT_RCV_MAX;
  decstat->first_frame = (Word16) 1;
  decstat->prev_nRcv_hi = (Word16) 0;
  decstat->prev_rate = (Word16) 0;
#if(WMOPS)
  move16();
  move16();
  move16();
  move16();
#endif

  /* init FEC variables */
  decstat->lp_ener_FER = (Word16) (256 * 60); /* Q8 */
  decstat->lastgood = G729EV_FEC_UNVOICED;
  decstat->plast_good = G729EV_FEC_UNVOICED;
  decstat->old_enrLP = (Word16) 0;  /*Q4 */
#if(WMOPS)
  move16();
  move16();
  move16();
  move16();
#endif
  G729EV_G729_Set_zero(decstat->synth_buf, G729EV_G729_PIT_MAX);

  /* initialize memory for median filter to smooth the gamma parameters of the postfilter */
  FOR(i = 0; i < G729EV_MAIN_NMAX; i++)
  {
    decstat->tab_Th[i] = (Word16) 0;
#if(WMOPS)
    move16();
#endif
  }
}


/*--------------------------------------------------------------------------*
 *  Function  G729EV_MAIN_Decode()                                          *
 *  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~                                          *
 *  Main decoder routine                                                    *
 *--------------------------------------------------------------------------*/

void G729EV_MAIN_Decode(DECSTATMAIN * decstat,      /* (i)  decoder states variables        */
                        Word16 * itu_192_bitstream, /* (i)  G.192 bitstream to decode       */
                        Word16 * tabout,            /* (o)  20 ms  speech signal            */
                        Word16 rate,                /* (i)  Decoding rate                   */
                        Word16 bfi                  /* (i)  Bad Frame Indicator             */
)
{
  G729EV_CELP2S_PARAM nb_celp_param;
  G729EV_MAIN_PFSTAT *pfstat;

  Word32    Ltmp;
  Word32    L_enr_q;            /* Q0 */

  Word16    celp_output[G729EV_MAIN_L_FRAME2];
  Word16    output_lo[G729EV_MAIN_L_FRAME2];
  Word16    output_hi[G729EV_MAIN_L_FRAME2];
  Word16    output_hiTdbwe[G729EV_MAIN_L_FRAME2];
  Word16    diff_q[G729EV_MAIN_L_FRAME2];
  Word16    yq_lo[G729EV_MAIN_L_FRAME2];
  Word16    yq_hi[G729EV_MAIN_L_FRAME2];
  Word16    yt_hi[G729EV_MAIN_L_FRAME2];
  Word16    pst_in[G729EV_MAIN_L_FRAME2];
  Word16    parameters_tdbwe[G729EV_TDBWE_NB_PARAMETERS]; /* Q.10 */
  Word16    pf_in_buffer[G729EV_G729_M_LPC + G729EV_MAIN_L_FRAME2];
  Word16    coreExc[G729EV_MAIN_L_FRAME2], extExc[G729EV_MAIN_L_FRAME2], BfAq[4 * G729EV_G729_MP1];
  Word16    pitch_buf[G729EV_MAIN_NB_SUBFR];
  Word16    mem_syntmp[G729EV_G729_M];
  Word16    ind_fer[3];
  Word16    parm_FEC[13];
  Word16    coder_parameters[G729EV_G729_PRM_SIZE_MAX * 2 + 10];

  Word16   *ptr_Az;
  Word16   *pf_in;
  Word16   *coder_param_ptr;

  Word16    i_frame, i, j, ind;
  Word16    nb_bits_to_decode;
  Word16    nb_bits_left;
  Word16    nb_bits_used;
  Word16    nb_bits_max;
  Word16    norm_MDCT;
  Word16    norm_local;
  Word16    diff_norm;
  Word16    nRcv_hi;
  Word16    t0_first;           /* Pitch lag in 1st subframe   */
  Word16    ga1_post, ga2_post;
  Word16    tmp16;
  Word16    clas;
  Word16    FerPitch;
  Word16    begin_index_low, end_index_low, begin_index_high, end_index_high; /*beggining & end of the false alarm zone */


  /* set pointer to parameters */
  coder_param_ptr = coder_parameters;

  /* compute number of bits to decode */
  nb_bits_to_decode = rate / 50;

  /* set FEC variables */
  L_enr_q = (Word32) - 1;
  clas = decstat->lastgood;
  pitch_buf[0] = decstat->decStG729.pit_mem[0];
  pitch_buf[1] = decstat->decStG729.pit_mem[1];
  pitch_buf[2] = decstat->decStG729.pit_mem[2];
  pitch_buf[3] = decstat->decStG729.pit_mem[3];
#if(WMOPS)
  move32();
  move16();
  move16();
  move16();
  move16();
  move16();
  move16();
#endif
  ind_fer[0] = (Word16) - 1000;
  ind_fer[1] = (Word16) - 1000;
  ind_fer[2] = (Word16) - 1000;
#if(WMOPS)
  move16();
  move16();
  move16();
#endif

  /* set frame type (ftyp) for G.729B decoding */
#if(WMOPS)
  test();
#endif
  IF((decstat->g729b_bst) && (bfi))
  {
    IF(decstat->decStG729.past_ftyp == 1)
    {
      decstat->decStG729.ftyp[0] = 1;
      decstat->decStG729.ftyp[1] = 1;
    } ELSE
    {
      decstat->decStG729.ftyp[0] = 0;
      decstat->decStG729.ftyp[1] = 0;
    }
#if(WMOPS)
    move16();
    move16();
#endif
  }


#if(WMOPS)
  test();
  test();
#endif
  IF((!bfi) || ((decstat->g729b_bst) && (decstat->decStG729.ftyp[0] == 0)))
  {
    /************************************ decode received frame (bfi=0) **************************/

    /***************************
     * Initialize bit counters *
     ***************************/

    /* set number of bits for 20-ms frame */
    nb_bits_max = G729EV_MAX_BITRATE / 50;  /* maximal bit allocation (-> 32 kbit/s) */
    nb_bits_left = nb_bits_to_decode;       /* number of bits available for decoder */
    nb_bits_used = (Word16) 0;              /* number of bits used */
#if(WMOPS)
    move16();
    move16();
    move16();
#endif

    /*******************************************
     * Read bitstream and demultiplex parameters
     *******************************************/

    G729EV_MAIN_bit2param(itu_192_bitstream, nb_bits_to_decode, coder_parameters, ind_fer, decstat);

    /*********************************************************
     * decode FEC information (clas, puslse offset and energy)
     *********************************************************/

    IF(sub(rate, 12000) >= 0)
    {
      clas = G729EV_FEC_dec(&(decstat->lastgood), decstat->plast_good, decstat->prev_bfi, ind_fer, &L_enr_q, rate);
    }

    /************************************************************************
     * Update decoder CELP parameters if previous frame was erased (recovery)
     ************************************************************************/

    IF((sub(decstat->prev_bfi, 1) == 0) && (decstat->low_delay == 0))
    {
      coder_parameters[3] = G729EV_G729_Check_Parity_Pitch(coder_parameters[2], coder_parameters[3]);
#if(WMOPS)
      move16();
#endif
      /* The new clas is already known with the 14 kbit/s bitstream */
      G729EV_FEC_dec_bf(coder_parameters, decstat->old_celp_output, BfAq, G729EV_FEC_SINGLE_FRAME,
                        &(decstat->lastgood), pitch_buf, decstat->old_enrLP,
                        decstat->decStG729.old_exc, &(decstat->decStG729), clas, ind_fer[2]);

      /* Update to be done before decoding a good frame */
      FerPitch = shr(add(pitch_buf[0], G729EV_FEC_QPIT2), G729EV_FEC_SQPIT);
      if (sub(FerPitch, G729EV_G729_PIT_MIN) < 0)
      {
        FerPitch = G729EV_G729_PIT_MIN;
#if(WMOPS)
        move16();
#endif
      }
      if (sub(FerPitch, G729EV_G729_PIT_MAX) > 0)
      {
        FerPitch = G729EV_G729_PIT_MAX;
#if(WMOPS)
        move16();
#endif
      }

      G729EV_G729_UpdateMemTam(&decstat->decStG729, decstat->decStG729.lp_gainp, FerPitch);
      G729EV_G729_UpdateMemTam(&decstat->decStG729, decstat->decStG729.lp_gainp, FerPitch);