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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 : QUA_GAIN.C
Used for the floating point version of both
G.729 main body and G.729A
*/
/*****************************************************************************/
/* gain quantizer routines */
/*****************************************************************************/
#include
#include "typedef.h"
#include "version.h"
#ifdef VER_G729A
#include "ld8a.h"
#include "tab_ld8a.h"
#else
#include "ld8k.h"
#include "tab_ld8k.h"
#endif
/* prototypes of local functions */
static void gbk_presel(
FLOAT best_gain[], /* input : [0] unquantized pitch gain
[1] unquantized code gain */
int *cand1, /* output: index of best 1st stage vector */
int *cand2, /* output: index of best 2nd stage vector */
FLOAT gcode0 /* input : presearch for gain codebook */
);
/*----------------------------------------------------------------------------
* qua_gain - Quantization of pitch and codebook gains
*----------------------------------------------------------------------------
*/
int qua_gain( /* output: quantizer index */
FLOAT code[], /* input : fixed codebook vector */
FLOAT *g_coeff, /* input : correlation factors */
int l_subfr, /* input : fcb vector length */
FLOAT *gain_pit, /* output: quantized acb gain */
FLOAT *gain_code, /* output: quantized fcb gain */
int tameflag /* input : flag set to 1 if taming is needed */
)
{
/*
* MA prediction is performed on the innovation energy (in dB with mean *
* removed). *
* An initial predicted gain, g_0, is first determined and the correction *
* factor alpha = gain / g_0 is quantized. *
* The pitch gain and the correction factor are vector quantized and the *
* mean-squared weighted error criterion is used in the quantizer search. *
* CS Codebook , fast pre-selection version *
*/
static FLOAT past_qua_en[4]={(F)-14.0,(F)-14.0,(F)-14.0,(F)-14.0};
int i,j, index1, index2;
int cand1,cand2 ;
FLOAT gcode0 ;
FLOAT dist, dist_min, g_pitch, g_code;
FLOAT best_gain[2],tmp;
/*---------------------------------------------------*
*- energy due to innovation -*
*- predicted energy -*
*- predicted codebook gain => gcode0[exp_gcode0] -*
*---------------------------------------------------*/
gain_predict( past_qua_en, code, l_subfr, &gcode0);
/*-- pre-selection --*/
tmp = (F)-1./((F)4.*g_coeff[0]*g_coeff[2]-g_coeff[4]*g_coeff[4]) ;
best_gain[0] = ((F)2.*g_coeff[2]*g_coeff[1]-g_coeff[3]*g_coeff[4])*tmp ;
best_gain[1] = ((F)2.*g_coeff[0]*g_coeff[3]-g_coeff[1]*g_coeff[4])*tmp ;
if (tameflag == 1){
if(best_gain[0]> GPCLIP2) best_gain[0] = GPCLIP2;
}
/*----------------------------------------------*
* - presearch for gain codebook - *
*----------------------------------------------*/
gbk_presel(best_gain,&cand1,&cand2,gcode0) ;
/*-- selection --*/
dist_min = FLT_MAX_G729;
if(tameflag == 1) {
for (i=0;i(F)0.0){
/* pre select codebook #1 */
*cand1 = 0 ;
do{
if(y>thr1[*cand1]*gcode0) (*cand1)++ ;
else break ;
} while((*cand1)<(NCODE1-NCAN1)) ;
/* pre select codebook #2 */
*cand2 = 0 ;
do{
if(x>thr2[*cand2]*gcode0) (*cand2)++ ;
else break ;
} while((*cand2)<(NCODE2-NCAN2)) ;
}
else{
/* pre select codebook #1 */
*cand1 = 0 ;
do{
if(y