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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 : PWF.C 
 Used for the floating point version of G.729 main body 
 (not for G.729A) 
*/ 
 
#include  
#include "typedef.h" 
#include "ld8k.h" 
 
static int     smooth = 1; 
static FLOAT   lar_old[2] = {(F)0.0, (F)0.0}; 
 
/*---------------------------------------------------------------------------- 
 * perc_var -adaptive bandwidth expansion for perceptual weighting filter 
 *---------------------------------------------------------------------------- 
 */ 
void perc_var( 
 FLOAT *gamma1,         /* output: gamma1 value */ 
 FLOAT *gamma2,         /* output: gamma2 value */ 
 FLOAT *lsfint,         /* input : Interpolated lsf vector : 1st subframe */ 
 FLOAT *lsfnew,         /* input : lsf vector : 2nd subframe */ 
 FLOAT *r_c             /* input : Reflection coefficients */ 
) 
{ 
    FLOAT    lar[4]; 
    FLOAT   *lar_new; 
    FLOAT   *lsf; 
    FLOAT    critlar0, critlar1; 
    FLOAT    d_min, temp; 
    int      i, k; 
 
 
    lar_new = &lar[2]; 
 
    /* reflection coefficients --> lar */ 
    for (i=0; i<2; i++) 
        lar_new[i] = (FLOAT)log10( (double)( ( (F)1.0 + r_c[i]) / ((F)1.0 - r_c[i]))); 
 
    /* Interpolation of lar for the 1st subframe */ 
    for (i=0; i<2; i++) { 
        lar[i] = (F)0.5 * (lar_new[i] + lar_old[i]); 
        lar_old[i] = lar_new[i]; 
    } 
 
    for (k=0; k<2; k++) {    /* LOOP : gamma2 for 1st to 2nd subframes */ 
 
      /* ----------------------------------------------------- */ 
      /*   First criterion based on the first two lars         */ 
      /*                                                       */ 
      /* smooth == 1  ==>  gamma2 is set to 0.6                    */ 
      /*                   gamma1 is set to 0.94               */ 
      /*                                                       */ 
      /* smooth == 0  ==>  gamma2 can vary from 0.4 to 0.7     */ 
      /*                   (gamma2 = -6.0 dmin + 1.0)          */ 
      /*                   gamma1 is set to 0.98               */ 
      /* ----------------------------------------------------- */ 
        critlar0 = lar[2*k]; 
        critlar1 = lar[2*k+1]; 
 
        if (smooth != 0) { 
            if ((critlar0  THRESH_H1)) smooth = 0; 
        } 
        else { 
            if ((critlar0 > THRESH_L2)||(critlar1 < THRESH_H2)) smooth = 1; 
        } 
 
        if (smooth == 0) { 
     /* ------------------------------------------------------ */ 
     /* Second criterion based on the minimum distance between */ 
     /* two successives lsfs                                   */ 
     /* ------------------------------------------------------ */ 
            gamma1[k] = GAMMA1_0; 
            if (k == 0) lsf = lsfint; 
            else lsf = lsfnew; 
            d_min = lsf[1] - lsf[0]; 
            for (i=1; i GAMMA2_0_H) gamma2[k] = GAMMA2_0_H; 
            if (gamma2[k] < GAMMA2_0_L) gamma2[k] = GAMMA2_0_L; 
        } 
        else { 
            gamma1[k] = GAMMA1_1; 
            gamma2[k] = GAMMA2_1;; 
        } 
    } 
    return; 
}