funcg722.c

ITU-T G.191中包含的G.722语音压缩编解码程序

/*                                                   Version: 2.00 - 01.Jul.95
  ============================================================================

                          U    U   GGG    SSSS  TTTTT
                          U    U  G       S       T
                          U    U  G  GG   SSSS    T
                          U    U  G   G       S   T
                           UUU     GG     SSS     T

                   ========================================
                    ITU-T - USER'S GROUP ON SOFTWARE TOOLS
                   ========================================


       =============================================================
       COPYRIGHT NOTE: This source code, and all of its derivations,
       is subject to the "ITU-T General Public License". Please have
       it  read  in    the  distribution  disk,   or  in  the  ITU-T
       Recommendation G.191 on "SOFTWARE TOOLS FOR SPEECH AND  AUDIO
       CODING STANDARDS". 
       ** This code has  (C) Copyright by CNET Lannion A TSS/CMC **
       =============================================================


MODULE:         G722.C 7kHz ADPCM AT 64 KBIT/S MODULE ENCODER AND 
                DECODER FUNCTIONS

ORIGINAL BY:
    J-P PETIT 
    CNET - Centre Lannion A
    LAA-TSS                         Tel: [phone]
    Route de Tregastel - BP 40      Fax: [phone]
    F-22301 Lannion CEDEX           Email: [e-mail]
    FRANCE
    
   History:
   14.Mar.95    v1.0    Released for use ITU-T UGST software package Tool
                        based on the CNET's 07/01/90 version 2.00
   01.Jul.95    v2.0    Changed function declarations to work with 
                        many compilers; reformated <[e-mail]>
  ============================================================================
*/

#include <stdio.h>

/* Include state variable definition, function and operator prototypes */
#include "g722.h"


/* Local pseudo-functions */
#define parrec( a, b)  add( a, b )
#define recons( a, b)  add( a, b )
#define subtra( a, b)  sub( a, b )
#define predic( a, b)  add( a, b )


/*___________________________________________________________________________
                                                                            
    Function Name : lsbcod                                                  
                                                                            
    Purpose :                                                               
                                                                            
     Encode lower subband of incomung speech/music.                         
                                                                            
    Inputs :                                                                
      xh - Low sub-band portion of the input sample                         
      rs - reset flag (read-only)                                           
      s  - pointer to state variable (read/write)                           
                                                                            
    Return Value :                                                          
     Encoded sample as a 16-bit word                                        
 ___________________________________________________________________________
*/
#define AL   s->al
#define BL   s->bl
#define DETL s->detl
#define DLT  s->dlt
#define NBL  s->nbl
#define PLT  s->plt
#define RLT  s->rlt
#define SL   s->sl
#define SPL  s->spl
#define SZL  s->szl

Word16 
lsbcod (xl, rs, s)
Word16 xl;
Word16 rs;
g722_state *s;
{
  Word16          el, nbpl, il;

  if (rs == 1)
  {
    DETL = 32;
    SL = SPL = SZL = NBL = 0;
    AL[1] = AL[2] = 0;
    BL[1] = BL[2] = BL[3] = BL[4] = BL[5] = BL[6] = 0;
    DLT[0] = DLT[1] = DLT[2] = DLT[3] = DLT[4] = DLT[5] = DLT[6] = 0;
    PLT[0] = PLT[1] = PLT[2] = 0;
    RLT[0] = RLT[1] = RLT[2] = 0;
    return (0);
  }

  el = subtra (xl, SL);
  il = quantl (el, DETL);
  DLT[0] = invqal (il, DETL);
  nbpl = logscl (il, NBL);
  NBL = nbpl;
  DETL = scalel (nbpl);
  PLT[0] = parrec (DLT[0], SZL);
  RLT[0] = recons (SL, DLT[0]);
  upzero (DLT, BL);
  uppol2 (AL, PLT);
  uppol1 (AL, PLT);
  SZL = filtez (DLT, BL);
  SPL = filtep (RLT, AL);
  SL = predic (SPL, SZL);

  /* Return encoded sample */
  return (il);
}
#undef AL
#undef BL
#undef DETL
#undef DLT
#undef NBL
#undef PLT
#undef RLT
#undef SL
#undef SPL
#undef SZL
/* ........................ End of lsbcod() ........................ */


/*___________________________________________________________________________
                                                                            
    Function Name : hsbcod                                                  
                                                                            
    Purpose :                                                               
                                                                            
     Encode upper sub-band of incoming speech or music.                     
                                                                            
    Inputs :                                                                
      xh - High sub-band portion of the input sample                        
      rs - reset flag (read-only)                                           
      s  - pointer to state variable (read/write)                           
                                                                            
    Return Value :                                                          
     ADPCM code for the high-band portion of the input sample as a          
     16-bit word.                                                           
                                                                            
 ___________________________________________________________________________
*/
#define AH   s->ah
#define BH   s->bh
#define DETH s->deth
#define DH  s->dh 
#define NBH  s->nbh
#define PH  s->ph 
#define RH  s->rh 
#define SH   s->sh
#define SPH  s->sph 
#define SZH  s->szh

Word16 
hsbcod (xh, rs, s)
Word16 xh;
Word16 rs;
g722_state *s;
{
  Word16          eh, nbph, ih;

  if (rs == 1)
  {
    DETH = 8;
    SH = SPH = SZH = NBH = 0;
    AH[1] = AH[2] = 0;
    BH[1] = BH[2] = BH[3] = BH[4] = BH[5] = BH[6] = 0;
    DH[0] = DH[1] = DH[2] = DH[3] = DH[4] = DH[5] = DH[6] = 0;
    PH[0] = PH[1] = PH[2] = 0;
    RH[0] = RH[1] = RH[2] = 0;

    return (0);
  }

  eh = subtra (xh, SH);
  ih = quanth (eh, DETH);
  DH[0] = invqah (ih, DETH);
  nbph = logsch (ih, NBH);
  NBH = nbph;
  DETH = scaleh (nbph);
  PH[0] = parrec (DH[0], SZH);
  RH[0] = recons (SH, DH[0]);
  upzero (DH, BH);
  uppol2 (AH, PH);
  uppol1 (AH, PH);
  SZH = filtez (DH, BH);
  SPH = filtep (RH, AH);
  SH = predic (SPH, SZH);

  return (ih);

}
#undef AH
#undef BH
#undef DETH
#undef DH
#undef NBH
#undef PH
#undef RH
#undef SH
#undef SPH
#undef SZH
/* ........................ End of hsbcod() ........................ */



/*___________________________________________________________________________
                                                                            
    Function Name : lsbdec                                                  
                                                                            
    Purpose :                                                               
                                                                            
     Decode lower subband of incomung speech/music.                         
                                                                            
    Inputs :                                                                
      ilr - ADPCM encoding of the low sub-band                              
      mode - G.722 operation mode                                           
      rs  - reset flag (read-only)                                          
      s   - pointer to state variable (read/write)                          
                                                                            
    Return Value :                                                          
     Decoded low-band portion of the recovered sample as a 16-bit word      
 ___________________________________________________________________________
*/
#define AL   s->al
#define BL   s->bl
#define DETL s->detl
#define DLT  s->dlt
#define NBL  s->nbl
#define PLT  s->plt
#define RLT  s->rlt
#define SL   s->sl
#define SPL  s->spl
#define SZL  s->szl

Word16 
lsbdec (ilr, mode, rs, s)
Word16 ilr;
Word16 mode;
Word16 rs;
g722_state *s;
{
  Word16          dl, rl, nbpl, yl;

  if (rs == 1)
  {
    DETL = 32;
    SL = SPL = SZL = NBL = 0;
    AL[1] = AL[2] = 0;
    BL[1] = BL[2] = BL[3] = BL[4] = BL[5] = BL[6] = 0;
    DLT[0] = DLT[1] = DLT[2] = DLT[3] = DLT[4] = DLT[5] = DLT[6] = 0;
    PLT[0] = PLT[1] = PLT[2] = 0;
    RLT[0] = RLT[1] = RLT[2] = 0;

    return (0);
  }

  dl = invqbl (ilr, DETL, mode);
  rl = recons (SL, dl);
  yl = limit (rl);
  DLT[0] = invqal (ilr, DETL);
  nbpl = logscl (ilr, NBL);
  NBL = nbpl;
  DETL = scalel (nbpl);
  PLT[0] = parrec (DLT[0], SZL);
  RLT[0] = recons (SL, DLT[0]);
  upzero (DLT, BL);
  uppol2 (AL, PLT);
  uppol1 (AL, PLT);
  SZL = filtez (DLT, BL);
  SPL = filtep (RLT, AL);
  SL = predic (SPL, SZL);

  return (yl);

}
#undef AL
#undef BL
#undef DETL
#undef DLT
#undef NBL
#undef PLT
#undef RLT
#undef SL
#undef SPL
#undef SZL
/* ........................ End of lsbdec() ........................ */


/*___________________________________________________________________________
                                                                            
    Function Name : hsbdec                                                  
                                                                            
    Purpose :                                                               
                                                                            
     Decode lower subband of incomung speech/music.                         
                                                                            
    Inputs :                                                                
      ih  - ADPCM encoding of the high sub-band                             
      rs  - reset flag (read-only)                                          
      s   - pointer to state variable (read/write)                          
                                                                            
    Return Value :                                                          
     Decoded high-band portion of the recovered sample as a 16-bit word     
 ___________________________________________________________________________