g723dec.c

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//g.723.1decode program implementation

/* standard library interface */
#include<stdlib.h>
#include<stdio.h>
#include<string.h>

#include "g723dec.h"

//typedef struct _g723dec_obj g723dec_obj;
//typedef struct _Line     Line;

void Decoder_Alloc(int *size)
{
 *size=sizeof(g723dec_obj);
}  

void Init_Dec_Cng(g723dec_obj *g723dec)
{
 g723dec->CngSeed=12345;
 g723dec->preFtyp=1;
 g723dec->SidGain=0;
 ippsCopy_16s(LspDcTable,g723dec->LspSid,lpclen);
}

void Init_Decoder(g723dec_obj **g723dec)
{
 int i,size;
 
 Decoder_Alloc(&size);
 *g723dec=(g723dec_obj *)malloc(size);
 
 ippsZero_16s((short *)(*g723dec),sizeof(g723dec_obj)>>1);
 for(i=0;i<lpclen;i++)
   (*g723dec)->preLsp[i]=LspDcTable[i];   
 Init_Dec_Cng(*g723dec); 
 (*g723dec)->GctrlGain=(short)0x1000;  // the sample set it to 0x1000 ?
 return;
}

void Dec_Cng(g723dec_obj *g723dec, short Ftyp, Line *line, short *Vout, short *lpc)
{
  int i;
  char *buf;
  short *lsp_vec;

  lsp_vec=(short *)malloc(lpclen*sizeof(short));
  if(Ftyp==2) { // SID Frame
   DecodeSIDGain_G723_16s(line->ampindex[0],&g723dec->SidGain);
   LSFQuantInv_G723_32s16s(line->lspID,g723dec->preLsp,lsp_vec,line->Crc);
  }else {
   if(g723dec->preFtyp == 1) {  /* Case of 1st SID frame erased */
       QuantSIDGain_G723_16s(&g723dec->SidGain, &g723dec->SidSfs, 0, &i);
   //    QuantSIDGain_G723_16s(&g723dec->SidGain, &g723dec->CurGain, 0, &i);
       DecodeSIDGain_G723_16s(i,&g723dec->SidGain);                                
        }
  }
  if(g723dec->preFtyp == 1) 
     g723dec->CurGain = g723dec->SidGain;
  else  /* update gain */
     g723dec->CurGain = ( 7*g723dec->CurGain + g723dec->SidGain) >> 3 ;
     
  buf=(char *)malloc(ComfortNoiseExcitation_G723_16s_Buff_Size);
  ComfortNoiseExcitation_G723_16s(g723dec->CurGain,g723dec->preExc,Vout,&g723dec->CngSeed,line->olp,line->closelag,line->adptgid,g723dec->rate,buf);
  free(buf);
  
 // ippsZero_16s(Vout,fsize);
  LspInterpolation_G723(lsp_vec,g723dec->preLsp,lpc); 
//  ippsZero_16s(lpc,4*lpclen);
  ippsCopy_16s(lsp_vec,g723dec->preLsp,lpclen);
  free(lsp_vec);
}  

void Dec_by_frame(g723dec_obj *g723dec,char *bitstream,short Crc,short *Vout)
{
 Line *line;
 int i,j;
 short lsp_vec[lpclen];
 short lpc[lpclen*4];
 short Temp[pitchmax+fsize];
 short *Dpnt;
 short post_delay[4];
 short pitch_gain[4];
 short scale_gain[4];
 short Ftyp;
 
 
 ippsZero_16s(Vout,fsize);
 ippsZero_16s(lpc,4*lpclen);
 ippsZero_16s(lsp_vec,lpclen);
// printf("Welcome to Dec_by_frame\n");
 line=(Line *)malloc(sizeof(Line));
 line->Crc=Crc;
 if(line->Crc==0) {
 //unpack bitstream 
 Unpack(bitstream,line,&g723dec->rate,&Ftyp);
 }
 
 if(line->Crc !=0) {                // if it is transmitting or operate error, count on the past Ftyp 
   if(g723dec->preFtyp==1) Ftyp=1;
   else
     Ftyp=0;
  }  
 if(line->Crc==0)                 //calculate the number of adjacent error frames 
   g723dec->err_count=0;
 else
   g723dec->err_count++;
 if(g723dec->err_count>=3)
   g723dec->err_count=3;
// Ftyp=0;
 if(Ftyp!=1) {
   Dec_Cng(g723dec, Ftyp, line, Vout, lpc);
   }
 else {
  //decode lsp_index to lsp
  LSFQuantInv_G723_32s16s(line->lspID,g723dec->preLsp,lsp_vec,line->Crc);
  LspInterpolation_G723(lsp_vec,g723dec->preLsp,lpc);
  
  ippsCopy_16s(lsp_vec,g723dec->preLsp,lpclen);
  
  //update interGain
  if(g723dec->err_count==0) 
    g723dec->UnvGain=FcbkGainTable[(line->ampindex[2]+line->ampindex[3])>>1]; //unvoiced use 
  else
    g723dec->UnvGain=(g723dec->UnvGain*3+2)>>2;                      // decrease by 2.5dB every frame after the first lost frame
  
  ippsCopy_16s(g723dec->preExc,Temp,pitchmax);
  Dpnt=&Temp[pitchmax];
  if(g723dec->err_count==0) {
   for(i=0;i<4;i++) {
     int T0;
     short T0_gain;
     /* Fixed codebook excitation. */
     FixedCodebookVector_G723_16s(line->pos[i],line->sign[i],line->ampindex[i],line->grid[i],line->adptgid[i],i,g723dec->rate,Dpnt,&T0,&T0_gain);
     
     if (g723dec->rate==0 ){ /* rate63*/
        if(line->traindrt[i]==1 ) {
          short Tmp[sfsize] ;
          ippsCopy_16s(Dpnt,Tmp,sfsize);
          /*  Generation of a Dirac train. Section 2.15 */
          for (j=line->olp[i>>1];j<sfsize;j+=line->olp[i>>1])     ippsAdd_16s_I(Tmp,&Dpnt[j],sfsize-j);
        }
     }else{ /*rate53*/
       T0 +=line->olp[i>>1]-1+line->closelag[i];       
       if(T0<sfsize-2) 
         HarmonicFilter2_I(&Dpnt[T0],T0,T0_gain,sfsize-T0);
      }
      
     /* Adaptive codebook excitation. Section 3.4 */
     {
      short adptContr[sfsize];
      ippsDecodeAdaptiveVector_G723_16s(line->olp[i>>1],line->closelag[i],line->adptgid[i],&Temp[sfsize*i],adptContr,rate_vec[g723dec->rate]);
                /* Codebook contributions to excitation. */
      ShiftL_16s(Dpnt,1,Dpnt,sfsize);
      ippsAdd_16s_I(adptContr,Dpnt,sfsize);           //add the adaptive-contribution and the fixed-contribution
      Dpnt += sfsize ;
     }
   }// end of subframe
   
   ippsCopy_16s(&Temp[pitchmax],Vout,fsize);                   
   
   /* Interpolation index calculation. Section 3.10 */
   Comp_Info(Temp, line->olp[1],&g723dec->SidGain, &g723dec->SidSfs, &g723dec->VoiceDelay);   //!!!!!!!!!
                                                                                      //after it Temp changed
   /* Pitch post filter coefficients calculation.  Section 3.6 */
   for ( i = 0 ; i < 4 ; i ++ )                                        //sure to do the post pitch filter
     ippsPitchPostFilter_G723_16s(line->olp[i>>1],&Temp[pitchmax],&post_delay[i],&pitch_gain[i],&scale_gain[i],(short)i,rate_vec[g723dec->rate]);                              
                  
   ippsCopy_16s(g723dec->preExc,Temp,pitchmax);
   ippsCopy_16s(Vout,&Temp[pitchmax],fsize);
      
   /* Pitch post filtering. Section 3.6 */
   for ( i = 0 ; i < 4 ; i ++ )                  
     PitchPost_G723_Sfs(&Temp[pitchmax+i*sfsize],&Vout[i*sfsize],post_delay[i],pitch_gain[i],scale_gain[i],15);   //gain-Q15
 //  fwrite(Vout,sizeof(short),fsize,fp);   
   ippsCopy_16s(g723dec->preLsp,g723dec->LspSid,lpclen);
  }else {
   /* Frame erasure. Section 3.10 */
   if ( g723dec->err_count>= 3 ) {    /* Test for clearing */
      ippsZero_16s(Vout,fsize);
      ippsZero_16s(Temp,fsize+pitchmax);
   }else
      ResidualInterpolation_G723_16s_I(Temp,Vout,g723dec->VoiceDelay,g723dec->UnvGain,&g723dec->UnvSeed);
    
  }
  
  ippsCopy_16s(&Temp[fsize],g723dec->preExc,pitchmax);
  g723dec->CngSeed = 12345;
 }
  g723dec->preFtyp=Ftyp;
  /* Speech synthesis. Section 3.7 */
  
  Dpnt=Vout ;
  for ( i = 0 ; i < 4 ; i ++ ) {
     int SythEner;

     ippsSynthesisFilter_G723_16s(&lpc[i*lpclen], Dpnt,g723dec->SythD1,Dpnt);
     
        /* Formant post filter. Section 3.8 */
     FormantPostFilter_G723_I(Dpnt,&SythEner,&lpc[i*lpclen],&g723dec->k_old,g723dec->formantD1);
     
     GainControl_G723_I(Dpnt,SythEner,&g723dec->GctrlGain);   
   //  fwrite(Dpnt,sizeof(short),sfsize,fp);       
      Dpnt += sfsize ;
    }
    return;   
}