cod_amr.c

arm音频编解码库

/*
*****************************************************************************
*
*      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             : cod_amr.c
*      Purpose          : Main encoder routine operating on a frame basis.
*
*****************************************************************************
*/
#include "cod_amr.h"
const char cod_amr_id[] = "@(#)$Id $" cod_amr_h;

/*
*****************************************************************************
*                         INCLUDE FILES
*****************************************************************************
*/

#include <stdio.h>
#include <stdlib.h>
#include "typedef.h"
#include "basic_op.h"
#include "count.h"
#include "cnst.h"
#include "copy.h"
#include "set_zero.h"
#include "qua_gain.h"

#include "lpc.h"
#include "lsp.h"
#include "pre_big.h"
#include "ol_ltp.h"
#include "p_ol_wgh.h"
#include "spreproc.h"
#include "cl_ltp.h"
#include "pred_lt.h"
#include "spstproc.h"
#include "cbsearch.h"
#include "gain_q.h"
#include "copy.h"
#include "convolve.h"
#include "ton_stab.h"
#include "vad.h"
#include "dtx_enc.h"

/*
*****************************************************************************
*                         LOCAL VARIABLES AND TABLES
*****************************************************************************
*/

/*
*****************************************************************************
*                         PUBLIC VARIABLES AND TABLES
*****************************************************************************
*/
/* Spectral expansion factors */

static const Word16 gamma1[M] =
{
   30802, 28954, 27217, 25584, 24049,
   22606, 21250, 19975, 18777, 17650
};

/* gamma1 differs for the 12k2 coder */
static const Word16 gamma1_12k2[M] =
{
    29491, 26542, 23888, 21499, 19349,
    17414, 15672, 14105, 12694, 11425
};

static const Word16 gamma2[M] =
{
   19661, 11797, 7078, 4247, 2548,
   1529, 917, 550, 330, 198
};

/*
*****************************************************************************
*                         PUBLIC PROGRAM CODE
*****************************************************************************
*/
/*
**************************************************************************
*
*  Function    : cod_amr_init
*  Purpose     : Allocates memory and initializes state variables
*
**************************************************************************
*/
int cod_amr_init (cod_amrState **state, Flag dtx)
{
  cod_amrState* s;

  if (state == (cod_amrState **) NULL){
      fprintf(stderr, "cod_amr_init: invalid parameter\n");
      return -1;
  }
  *state = NULL;
 
  /* allocate memory */
  if ((s= (cod_amrState *) malloc(sizeof(cod_amrState))) == NULL){
      fprintf(stderr, "cod_amr_init: can not malloc state structure\n");
      return -1;
  }

  s->lpcSt = NULL;
  s->lspSt = NULL;
  s->clLtpSt = NULL;
  s->gainQuantSt = NULL;
  s->pitchOLWghtSt = NULL;
  s->tonStabSt = NULL;    
  s->vadSt = NULL;
  s->dtx_encSt = NULL;
  s->dtx = dtx;
  
  /* Init sub states */
  if (cl_ltp_init(&s->clLtpSt) ||
      lsp_init(&s->lspSt) ||
      gainQuant_init(&s->gainQuantSt) ||
      p_ol_wgh_init(&s->pitchOLWghtSt) ||
      ton_stab_init(&s->tonStabSt) ||      
#ifndef VAD2
      vad1_init(&s->vadSt) ||
#else
      vad2_init(&s->vadSt) ||
#endif
      dtx_enc_init(&s->dtx_encSt) ||
      lpc_init(&s->lpcSt)) {
     cod_amr_exit(&s);
     return -1;
  }
  
  cod_amr_reset(s);
  
  *state = s;
  
  return 0;
}
 
/*
**************************************************************************
*
*  Function    : cod_amr_reset
*  Purpose     : Resets state memory
*
**************************************************************************
*/
int cod_amr_reset (cod_amrState *st)
{
   Word16 i;
    
   if (st == (cod_amrState *) NULL){
      fprintf(stderr, "cod_amr_reset: invalid parameter\n");
      return -1;
   }
  
   /*-----------------------------------------------------------------------*
    *          Initialize pointers to speech vector.                        *
    *-----------------------------------------------------------------------*/
      
   st->new_speech = st->old_speech + L_TOTAL - L_FRAME;   /* New speech     */
   
   st->speech = st->new_speech - L_NEXT;                  /* Present frame  */
   
   st->p_window = st->old_speech + L_TOTAL - L_WINDOW;    /* For LPC window */
   st->p_window_12k2 = st->p_window - L_NEXT; /* EFR LPC window: no lookahead */
   
   /* Initialize static pointers */
   
   st->wsp = st->old_wsp + PIT_MAX;
   st->exc = st->old_exc + PIT_MAX + L_INTERPOL;
   st->zero = st->ai_zero + MP1;
   st->error = st->mem_err + M;
   st->h1 = &st->hvec[L_SUBFR];
   
   /* Static vectors to zero */
   
   Set_zero(st->old_speech, L_TOTAL);
   Set_zero(st->old_exc,    PIT_MAX + L_INTERPOL);
   Set_zero(st->old_wsp,    PIT_MAX);
   Set_zero(st->mem_syn,    M);
   Set_zero(st->mem_w,      M);
   Set_zero(st->mem_w0,     M);
   Set_zero(st->mem_err,    M);
   Set_zero(st->zero,       L_SUBFR);
   Set_zero(st->hvec,       L_SUBFR);    /* set to zero "h1[-L_SUBFR..-1]" */

   /* OL LTP states */
   for (i = 0; i < 5; i++)
   {
      st->old_lags[i] = 40; 
   }
   
   /* Reset lpc states */
   lpc_reset(st->lpcSt);
   
   /* Reset lsp states */
   lsp_reset(st->lspSt);
    
   /* Reset clLtp states */
   cl_ltp_reset(st->clLtpSt);
   
   gainQuant_reset(st->gainQuantSt);

   p_ol_wgh_reset(st->pitchOLWghtSt);

   ton_stab_reset(st->tonStabSt);   

#ifndef VAD2
   vad1_reset(st->vadSt);
#else
   vad2_reset(st->vadSt);
#endif 
   
   dtx_enc_reset(st->dtx_encSt);

   st->sharp = SHARPMIN;
   
   return 0;
}
 
/*
**************************************************************************
*
*  Function    : cod_amr_exit
*  Purpose     : The memory used for state memory is freed
*
**************************************************************************
*/
void cod_amr_exit (cod_amrState **state)
{
   if (state == NULL || *state == NULL)
      return;
   
   /* dealloc members */
   lpc_exit(&(*state)->lpcSt);
   lsp_exit(&(*state)->lspSt);
   gainQuant_exit(&(*state)->gainQuantSt);
   cl_ltp_exit(&(*state)->clLtpSt);
   p_ol_wgh_exit(&(*state)->pitchOLWghtSt);
   ton_stab_exit(&(*state)->tonStabSt);
#ifndef VAD2
   vad1_exit(&(*state)->vadSt);
#else
   vad2_exit(&(*state)->vadSt);
#endif 
   dtx_enc_exit(&(*state)->dtx_encSt);

   /* deallocate memory */
   free(*state);
   *state = NULL;
   
   return;
}

/***************************************************************************
 *   FUNCTION:   cod_amr_first
 *
 *   PURPOSE:  Copes with look-ahead.
 *
 *   INPUTS:
 *       No input argument are passed to this function. However, before
 *       calling this function, 40 new speech data should be copied to the
 *       vector new_speech[]. This is a global pointer which is declared in
 *       this file (it points to the end of speech buffer minus 200).
 *
 ***************************************************************************/
 
int cod_amr_first(cod_amrState *st,     /* i/o : State struct           */
                  Word16 new_speech[])  /* i   : speech input (L_FRAME) */
{ 
   Copy(new_speech,&st->new_speech[-L_NEXT], L_NEXT);
   /*   Copy(new_speech,st->new_speech,L_FRAME); */
  
   return 0;
}


/***************************************************************************
 *   FUNCTION: cod_amr
 *
 *   PURPOSE:  Main encoder routine.
 *
 *   DESCRIPTION: This function is called every 20 ms speech frame,
 *       operating on the newly read 160 speech samples. It performs the
 *       principle encoding functions to produce the set of encoded parameters
 *       which include the LSP, adaptive codebook, and fixed codebook
 *       quantization indices (addresses and gains).
 *
 *   INPUTS:
 *       No input argument are passed to this function. However, before
 *       calling this function, 160 new speech data should be copied to the
 *       vector new_speech[]. This is a global pointer which is declared in
 *       this file (it points to the end of speech buffer minus 160).
 *
 *   OUTPUTS:
 *
 *       ana[]:     vector of analysis parameters.
 *       synth[]:   Local synthesis speech (for debugging purposes)
 *
 ***************************************************************************/
int cod_amr(
    cod_amrState *st,          /* i/o : State struct                   */
    enum Mode mode,            /* i   : AMR mode                       */
    Word16 new_speech[],       /* i   : speech input (L_FRAME)         */
    Word16 ana[],              /* o   : Analysis parameters            */
    enum Mode *usedMode,       /* o   : used mode                    */
    Word16 synth[]             /* o   : Local synthesis                */
)
{
   /* LPC coefficients */
   Word16 A_t[(MP1) * 4];      /* A(z) unquantized for the 4 subframes */
   Word16 Aq_t[(MP1) * 4];     /* A(z)   quantized for the 4 subframes */
   Word16 *A, *Aq;             /* Pointer on A_t and Aq_t              */
   Word16 lsp_new[M];
   
   /* Other vectors */
   Word16 xn[L_SUBFR];         /* Target vector for pitch search       */
   Word16 xn2[L_SUBFR];        /* Target vector for codebook search    */
   Word16 code[L_SUBFR];       /* Fixed codebook excitation            */
   Word16 y1[L_SUBFR];         /* Filtered adaptive excitation         */
   Word16 y2[L_SUBFR];         /* Filtered fixed codebook excitation   */
   Word16 gCoeff[6];           /* Correlations between xn, y1, & y2:   */
   Word16 res[L_SUBFR];        /* Short term (LPC) prediction residual */
   Word16 res2[L_SUBFR];       /* Long term (LTP) prediction residual  */

   /* Vector and scalars needed for the MR475 */
   Word16 xn_sf0[L_SUBFR];     /* Target vector for pitch search       */
   Word16 y2_sf0[L_SUBFR];     /* Filtered codebook innovation         */   
   Word16 code_sf0[L_SUBFR];   /* Fixed codebook excitation            */
   Word16 h1_sf0[L_SUBFR];     /* The impulse response of sf0          */
   Word16 mem_syn_save[M];     /* Filter memory                        */
   Word16 mem_w0_save[M];      /* Filter memory                        */
   Word16 mem_err_save[M];     /* Filter memory                        */
   Word16 sharp_save;          /* Sharpening                           */
   Word16 evenSubfr;           /* Even subframe indicator              */ 
   Word16 T0_sf0 = 0;          /* Integer pitch lag of sf0             */  
   Word16 T0_frac_sf0 = 0;     /* Fractional pitch lag of sf0          */  
   Word16 i_subfr_sf0 = 0;     /* Position in exc[] for sf0            */
   Word16 gain_pit_sf0;        /* Quantized pitch gain for sf0         */
   Word16 gain_code_sf0;       /* Quantized codebook gain for sf0      */
    
   /* Scalars */
   Word16 i_subfr, subfrNr;
   Word16 T_op[L_FRAME/L_FRAME_BY2];
   Word16 T0, T0_frac;
   Word16 gain_pit, gain_code;

   /* Flags */
   Word16 lsp_flag = 0;        /* indicates resonance in LPC filter */   
   Word16 gp_limit;            /* pitch gain limit value            */