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/*
ITU-T G.729 Annex C+ - Reference C code for floating point
implementation of G.729 Annex C+
(integration of Annexes B, D and E)
Version 2.1 of October 1999
*/
/*
File : DEGAINCP.C
*/
#include "typedef.h"
#include "ld8k.h"
#include "tab_ld8k.h"
#include "ld8cp.h"
#include "tabld8cp.h"
static FLOAT past_qua_en[4]={(F)-14.0,(F)-14.0,(F)-14.0,(F)-14.0};
/*----------------------------------------------------------------------------
* dec_gain - decode the adaptive and fixed codebook gains
*----------------------------------------------------------------------------
*/
void dec_gaine(
int index, /* input : quantizer index */
FLOAT code[], /* input : fixed code book vector */
int l_subfr, /* input : subframe size */
int bfi, /* input : bad frame indicator good = 0 */
FLOAT *gain_pit, /* output: quantized acb gain */
FLOAT *gain_code, /* output: quantized fcb gain */
int rate, /* (i) : number of bits per frame */
FLOAT gain_pit_mem,
FLOAT gain_cod_mem,
FLOAT *c_muting,
int count_bfi,
int stationnary
)
{
int index1,index2;
FLOAT gcode0, g_code;
/*----------------- Test erasure ---------------*/
if (bfi != 0) {
if(rate == G729E) {
if (count_bfi < 2) {
if (stationnary) *gain_pit = (F)1.;
else *gain_pit = (F)0.95;
*gain_code = gain_cod_mem;
}
else {
*gain_pit = gain_pit_mem * (*c_muting);
*gain_code = gain_cod_mem * (*c_muting);
if (stationnary) {
if (count_bfi > 10) *c_muting *= (F)0.995;
}
else *c_muting *= (F)0.98;
}
}
else {
*gain_pit *= (F)0.9;
if(*gain_pit > (F)0.9) *gain_pit=(F)0.9;
*gain_code *= (F)0.98;
}
/*----------------------------------------------*
* update table of past quantized energies *
* (frame erasure) *
*----------------------------------------------*/
gain_update_erasure(past_qua_en);
return;
}
/*-------------- Decode pitch gain ---------------*/
index1 = imap1[index>>NCODE2_B] ;
index2 = imap2[index & (NCODE2-1)] ;
*gain_pit = gbk1[index1][0]+gbk2[index2][0] ;
/*-------------- Decode codebook gain ---------------*/
/*---------------------------------------------------*
*- energy due to innovation -*
*- predicted energy -*
*- predicted codebook gain => gcode0[exp_gcode0] -*
*---------------------------------------------------*/
gain_predict( past_qua_en, code, l_subfr, &gcode0);
/*-----------------------------------------------------------------*
* *gain_code = (gbk1[indice1][1]+gbk2[indice2][1]) * gcode0; *
*-----------------------------------------------------------------*/
g_code = gbk1[index1][1]+gbk2[index2][1];
*gain_code = g_code * gcode0;
/*----------------------------------------------*
* update table of past quantized energies *
*----------------------------------------------*/
gain_update( past_qua_en, g_code);
return;
}
void dec_gain_6k(
int index, /* input : quantizer index */
FLOAT code[], /* input : fixed code book vector */
int l_subfr, /* input : subframe size */
int bfi, /* input : bad frame indicator good = 0 */
FLOAT *gain_pit, /* output: quantized acb gain */
FLOAT *gain_code /* output: quantized fcb gain */
)
{
int index1,index2;
FLOAT gcode0, g_code;
/*----------------- Test erasure ---------------*/
if (bfi != 0)
{
*gain_pit *= (F)0.9;
if(*gain_pit > (F)0.9) *gain_pit=(F)0.9;
*gain_code *= (F)0.98;
/*----------------------------------------------*
* update table of past quantized energies *
* (frame erasure) *
*----------------------------------------------*/
gain_update_erasure(past_qua_en);
return;
}
/*-------------- Decode pitch gain ---------------*/
index1 = imap1_6k[index>>NCODE2_B_6K] ;
index2 = imap2_6k[index & (NCODE2_6K-1)] ;
*gain_pit = gbk1_6k[index1][0]+gbk2_6k[index2][0] ;
/*-------------- Decode codebook gain ---------------*/
/*---------------------------------------------------*
*- energy due to innovation -*
*- predicted energy -*
*- predicted codebook gain => gcode0[exp_gcode0] -*
*---------------------------------------------------*/
gain_predict( past_qua_en, code, l_subfr, &gcode0);
/*-----------------------------------------------------------------*
* *gain_code = (gbk1_6k[indice1][1]+gbk2_6k[indice2][1]) * gcode0; *
*-----------------------------------------------------------------*/
g_code = gbk1_6k[index1][1]+gbk2_6k[index2][1];
*gain_code = g_code * gcode0;
/*----------------------------------------------*
* update table of past quantized energies *
*----------------------------------------------*/
if(g_code < (F)0.2) g_code = (F)0.2;
gain_update( past_qua_en, g_code);
return;
}