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/* ITU-T G.729 Software Package Release 2 (November 2006) */ 
/* 
   ITU-T G.729 Annex C - Reference C code for floating point 
                         implementation of G.729 
                         Version 1.01 of 15.September.98 
*/ 
 
/* 
---------------------------------------------------------------------- 
                    COPYRIGHT NOTICE 
---------------------------------------------------------------------- 
   ITU-T G.729 Annex C ANSI C source code 
   Copyright (C) 1998, AT&T, France Telecom, NTT, University of 
   Sherbrooke.  All rights reserved. 
 
---------------------------------------------------------------------- 
*/ 
 
/* 
 File : TAMING.C 
 Used for the floating point version of both 
 G.729 main body and G.729A 
*/ 
 
/************************************************************************** 
 * Taming functions.                                                      * 
 **************************************************************************/ 
#include "typedef.h" 
#include "version.h" 
#ifdef VER_G729A 
 #include "ld8a.h" 
#else 
 #include "ld8k.h" 
#endif 
 
static FLOAT exc_err[4]; 
 
void init_exc_err(void) 
{ 
  int i; 
  for(i=0; i<4; i++) exc_err[i] = (FLOAT)1.; 
  return; 
} 
 
/************************************************************************** 
 * routine test_err - computes the accumulated potential error in the     * 
 * adaptive codebook contribution                                         * 
 **************************************************************************/ 
int test_err( /* (o) flag set to 1 if taming is necessary  */ 
int t0,       /* (i) integer part of pitch delay           */ 
int t0_frac   /* (i) fractional part of pitch delay        */ 
) 
{ 
 
    int i, t1, zone1, zone2, flag; 
    FLOAT maxloc; 
 
    t1 = (t0_frac > 0) ? (t0+1) : t0; 
 
    i = t1 - L_SUBFR - L_INTER10; 
    if(i < 0) i = 0; 
    zone1 = (int) ( (FLOAT)i * INV_L_SUBFR); 
 
    i = t1 + L_INTER10 - 2; 
    zone2 = (int)( (FLOAT)i * INV_L_SUBFR); 
 
    maxloc = (FLOAT)-1.; 
    flag = 0 ; 
    for(i=zone2; i>=zone1; i--) { 
        if(exc_err[i] > maxloc) maxloc = exc_err[i]; 
    } 
    if(maxloc > THRESH_ERR) { 
        flag = 1; 
    } 
    return(flag); 
} 
 
/************************************************************************** 
 *routine update_exc_err - maintains the memory used to compute the error * 
 * function due to an adaptive codebook mismatch between encoder and      * 
 * decoder                                                                * 
 **************************************************************************/ 
 
void update_exc_err( 
 FLOAT gain_pit,      /* (i) pitch gain */ 
 int t0             /* (i) integer part of pitch delay */ 
) 
{ 
    int i, zone1, zone2, n; 
    FLOAT worst, temp; 
 
    worst = (FLOAT)-1.; 
 
    n = t0- L_SUBFR; 
    if(n < 0) { 
        temp = (FLOAT)1. + gain_pit * exc_err[0]; 
        if(temp > worst) worst = temp; 
        temp = (FLOAT)1. + gain_pit * temp; 
        if(temp > worst) worst = temp; 
    } 
 
    else { 
        zone1 = (int) ((FLOAT)n * INV_L_SUBFR); 
 
        i = t0 - 1; 
        zone2 = (int)((FLOAT)i * INV_L_SUBFR); 
 
        for(i = zone1; i <= zone2; i++) { 
            temp = (FLOAT)1. + gain_pit * exc_err[i]; 
            if(temp > worst) worst = temp; 
        } 
    } 
 
    for(i=3; i>=1; i--) exc_err[i] = exc_err[i-1]; 
    exc_err[0] = worst; 
 
    return; 
}