dec_amr.c

Trolltech公司发布的图形界面操作系统。可在qt-embedded-2.3.10平台上编译为嵌入式图形界面操作系统。

/*************************************************************************
*
*      GSM AMR-NB speech codec   R98   Version 7.6.0   December 12, 2001
*                                R99   Version 3.3.0                
*                                REL-4 Version 4.1.0                
*
*****************************************************************************
*
*      File             : dec_amr.c
*      Purpose          : Decoding of one speech frame using given codec mode
*
*****************************************************************************
*/

/*
*****************************************************************************
*                         MODULE INCLUDE FILE AND VERSION ID
*****************************************************************************
*/
#include "dec_amr.h"
const char dec_amr_id[] = "@(#)$Id $" dec_amr_h;

#include <stdlib.h>
#include <stdio.h>
#include "typedef.h"
#include "basic_op.h"
#include "count.h"
#include "cnst.h"
#include "copy.h"
#include "set_zero.h"
#include "syn_filt.h"
#include "d_plsf.h"
#include "agc.h"
#include "int_lpc.h"
#include "dec_gain.h"
#include "dec_lag3.h"
#include "dec_lag6.h"
#include "d2_9pf.h"
#include "d2_11pf.h"
#include "d3_14pf.h"
#include "d4_17pf.h"
#include "d8_31pf.h"
#include "d1035pf.h"
#include "pred_lt.h"
#include "d_gain_p.h"
#include "d_gain_c.h"
#include "dec_gain.h"
#include "ec_gains.h"
#include "ph_disp.h"
#include "c_g_aver.h"
#include "int_lsf.h"
#include "lsp_lsf.h"
#include "lsp_avg.h"
#include "bgnscd.h"
#include "ex_ctrl.h"
#include "sqrt_l.h"
#include "frame.h"

#include "lsp.tab"
#include "bitno.tab"
#include "b_cn_cod.h"

/*
*****************************************************************************
*                         LOCAL VARIABLES AND TABLES
*****************************************************************************
*/
/*-----------------------------------------------------------------*
 *   Decoder constant parameters (defined in "cnst.h")             *
 *-----------------------------------------------------------------*
 *   L_FRAME       : Frame size.                                   *
 *   L_FRAME_BY2   : Half the frame size.                          *
 *   L_SUBFR       : Sub-frame size.                               *
 *   M             : LPC order.                                    *
 *   MP1           : LPC order+1                                   *
 *   PIT_MIN       : Minimum pitch lag.                            *
 *   PIT_MIN_MR122 : Minimum pitch lag for the MR122 mode.         *
 *   PIT_MAX       : Maximum pitch lag.                            *
 *   L_INTERPOL    : Length of filter for interpolation            *
 *   PRM_SIZE      : size of vector containing analysis parameters *
 *-----------------------------------------------------------------*/

/*
*****************************************************************************
*                         PUBLIC PROGRAM CODE
*****************************************************************************
*/
/*
**************************************************************************
*
*  Function    : Decoder_amr_init
*  Purpose     : Allocates and initializes state memory
*
**************************************************************************
*/
int Decoder_amr_init (Decoder_amrState **state)
{
  Decoder_amrState* s;
  Word16 i;
 
  if (state == (Decoder_amrState **) NULL){
      fprintf(stderr, "Decoder_amr_init: invalid parameter\n");
      return -1;
  }
  *state = NULL;
 
  /* allocate memory */
  if ((s= (Decoder_amrState *) malloc(sizeof(Decoder_amrState))) == NULL){
      fprintf(stderr, "Decoder_amr_init: can not malloc state structure\n");
      return -1;
  }
  
  s->T0_lagBuff = 40;
  s->inBackgroundNoise = 0;
  s->voicedHangover = 0;
  for (i = 0; i < 9; i++)
     s->ltpGainHistory[i] = 0;

  s->lsfState = NULL;
  s->ec_gain_p_st = NULL;
  s->ec_gain_c_st = NULL;  
  s->pred_state = NULL;
  s->ph_disp_st = NULL;
  s->dtxDecoderState = NULL;
  
  if (D_plsf_init(&s->lsfState) ||
      ec_gain_pitch_init(&s->ec_gain_p_st) ||
      ec_gain_code_init(&s->ec_gain_c_st) ||
      gc_pred_init(&s->pred_state) ||
      Cb_gain_average_init(&s->Cb_gain_averState) ||
      lsp_avg_init(&s->lsp_avg_st) ||      
      Bgn_scd_init(&s->background_state) ||      
      ph_disp_init(&s->ph_disp_st) || 
      dtx_dec_init(&s->dtxDecoderState)) {
      Decoder_amr_exit(&s);
      return -1;
  }
      
  Decoder_amr_reset(s, (enum Mode)0);
  *state = s;
  
  return 0;
}

/*
**************************************************************************
*
*  Function    : Decoder_amr_reset
*  Purpose     : Resets state memory
*
**************************************************************************
*/
int Decoder_amr_reset (Decoder_amrState *state, enum Mode mode)
{
  Word16 i;

  if (state == (Decoder_amrState *) NULL){
      fprintf(stderr, "Decoder_amr_reset: invalid parameter\n");
      return -1;
  }
  
  /* Initialize static pointer */
  state->exc = state->old_exc + PIT_MAX + L_INTERPOL;

  /* Static vectors to zero */
  Set_zero (state->old_exc, PIT_MAX + L_INTERPOL);

  if (mode != MRDTX)
     Set_zero (state->mem_syn, M);

  /* initialize pitch sharpening */
  state->sharp = SHARPMIN;
  state->old_T0 = 40;
     
  /* Initialize state->lsp_old [] */ 

  if (mode != MRDTX) {
      Copy(lsp_init_data, &state->lsp_old[0], M);
  }

  /* Initialize memories of bad frame handling */
  state->prev_bf = 0;
  state->prev_pdf = 0;
  state->state = 0;
  
  state->T0_lagBuff = 40;
  state->inBackgroundNoise = 0;
  state->voicedHangover = 0;
  if (mode != MRDTX) {
      for (i=0;i<9;i++)
          state->excEnergyHist[i] = 0;
  }
  
  for (i = 0; i < 9; i++)
     state->ltpGainHistory[i] = 0;

  Cb_gain_average_reset(state->Cb_gain_averState);
  if (mode != MRDTX)
     lsp_avg_reset(state->lsp_avg_st);
  D_plsf_reset(state->lsfState);
  ec_gain_pitch_reset(state->ec_gain_p_st);
  ec_gain_code_reset(state->ec_gain_c_st);

  if (mode != MRDTX)
     gc_pred_reset(state->pred_state);

  Bgn_scd_reset(state->background_state);
  state->nodataSeed = 21845;
  ph_disp_reset(state->ph_disp_st);
  if (mode != MRDTX)
     dtx_dec_reset(state->dtxDecoderState);
  
  return 0;
}

/*
**************************************************************************
*
*  Function    : Decoder_amr_exit
*  Purpose     : The memory used for state memory is freed
*
**************************************************************************
*/
void Decoder_amr_exit (Decoder_amrState **state)
{
  if (state == NULL || *state == NULL)
      return;
 
  D_plsf_exit(&(*state)->lsfState);
  ec_gain_pitch_exit(&(*state)->ec_gain_p_st);
  ec_gain_code_exit(&(*state)->ec_gain_c_st);
  gc_pred_exit(&(*state)->pred_state);
  Bgn_scd_exit(&(*state)->background_state);
  ph_disp_exit(&(*state)->ph_disp_st);
  Cb_gain_average_exit(&(*state)->Cb_gain_averState);
  lsp_avg_exit(&(*state)->lsp_avg_st);
  dtx_dec_exit(&(*state)->dtxDecoderState);
  
  /* deallocate memory */
  free(*state);
  *state = NULL;
  
  return;
}

/*
**************************************************************************
*
*  Function    : Decoder_amr
*  Purpose     : Speech decoder routine.
*
**************************************************************************
*/
int Decoder_amr (
    Decoder_amrState *st,      /* i/o : State variables                   */
    enum Mode mode,            /* i   : AMR mode                          */
    Word16 parm[],             /* i   : vector of synthesis parameters
                                        (PRM_SIZE)                        */
    enum RXFrameType frame_type, /* i   : received frame type             */
    Word16 synth[],            /* o   : synthesis speech (L_FRAME)        */
    Word16 A_t[]               /* o   : decoded LP filter in 4 subframes
                                        (AZ_SIZE)                         */
)
{
    /* LPC coefficients */
   
    Word16 *Az;                /* Pointer on A_t */
    
    /* LSPs */

    Word16 lsp_new[M];
    Word16 lsp_mid[M];

    /* LSFs */
    
    Word16 prev_lsf[M];
    Word16 lsf_i[M];    

    /* Algebraic codevector */

    Word16 code[L_SUBFR];

    /* excitation */

    Word16 excp[L_SUBFR];
    Word16 exc_enhanced[L_SUBFR];

    /* Scalars */

    Word16 i, i_subfr;
    Word16 T0, T0_frac, index, index_mr475 = 0;
    Word16 gain_pit, gain_code, gain_code_mix, pit_sharp, pit_flag, pitch_fac;
    Word16 t0_min, t0_max;
    Word16 delta_frc_low, delta_frc_range;
    Word16 tmp_shift;
    Word16 temp;
    Word32 L_temp;
    Word16 flag4;
    Word16 carefulFlag;
    Word16 excEnergy;
    Word16 subfrNr; 
    Word16 evenSubfr = 0;

    Word16 bfi = 0;   /* bad frame indication flag                          */
    Word16 pdfi = 0;  /* potential degraded bad frame flag                  */

    enum DTXStateType newDTXState;  /* SPEECH , DTX, DTX_MUTE */

    /* find the new  DTX state  SPEECH OR DTX */
    newDTXState = rx_dtx_handler(st->dtxDecoderState, frame_type);
    move16 ();   /* function result */
    
    /* DTX actions */
    test();
    if (sub(newDTXState, SPEECH) != 0 )
    {
       Decoder_amr_reset (st, MRDTX);

       dtx_dec(st->dtxDecoderState, 
               st->mem_syn, 
               st->lsfState, 
               st->pred_state,
               st->Cb_gain_averState,
               newDTXState,
               mode, 
               parm, synth, A_t);
       /* update average lsp */
       
       Lsf_lsp(st->lsfState->past_lsf_q, st->lsp_old, M);
       lsp_avg(st->lsp_avg_st, st->lsfState->past_lsf_q);
       goto the_end;
    }

    /* SPEECH action state machine  */
    test (); test (); test (); 
    if ((sub(frame_type, RX_SPEECH_BAD) == 0) || 
        (sub(frame_type, RX_NO_DATA) == 0) ||
        (sub(frame_type, RX_ONSET) == 0)) 
    {
       bfi = 1;                                          move16 ();
       test(); test();
       if ((sub(frame_type, RX_NO_DATA) == 0) ||
           (sub(frame_type, RX_ONSET) == 0))
       {
	  build_CN_param(&st->nodataSeed,
			 prmno[mode],
			 bitno[mode],
			 parm);
       }       
    }
    else if (sub(frame_type, RX_SPEECH_DEGRADED) == 0)
    {
       pdfi = 1;                                         move16 ();
    }
   
    
    test();
    if (bfi != 0)
    {
        st->state = add (st->state, 1);
    }
    else if (sub (st->state, 6) == 0)

    {
        st->state = 5;                                   move16 ();
    }
    else
    {
        st->state = 0;                                   move16 ();
    }
    
    test (); 
    if (sub (st->state, 6) > 0)
    {
        st->state = 6;                                   move16 ();
    }

    /* If this frame is the first speech frame after CNI period,     */
    /* set the BFH state machine to an appropriate state depending   */
    /* on whether there was DTX muting before start of speech or not */
    /* If there was DTX muting, the first speech frame is muted.     */