/**
* Quantization of pitch and codebook gains
*
* @param code input : fixed codebook vector
* @param g_coeff input : correlation factors
* @param l_subfr input : fcb vector length
* @param gain_pit output: quantized acb gain
* @param gain_code output: quantized fcb gain
* @param tameflag input : flag set to 1 if taming is needed
* @return quantizer index
*/
public int qua_gain(
float[] code,
float[] g_coeff,
int l_subfr,
FloatReference gain_pit,
FloatReference gain_code,
int tameflag
)
{
var FLT_MAX_G729 = Ld8k.FLT_MAX_G729;
var GP0999 = Ld8k.GP0999;
var GPCLIP2 = Ld8k.GPCLIP2;
var NCAN1 = Ld8k.NCAN1;
var NCAN2 = Ld8k.NCAN2;
var NCODE2 = Ld8k.NCODE2;
var gbk1 = TabLd8k.gbk1;
var gbk2 = TabLd8k.gbk2;
var map1 = TabLd8k.map1;
var map2 = TabLd8k.map2;
/*
* 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 *
*/
int i, j, index1 = 0, index2 = 0;
int cand1, cand2;
float gcode0;
float dist, dist_min, g_pitch, g_code;
var best_gain = new float[2];
float tmp;
/*---------------------------------------------------*
*- energy due to innovation -*
*- predicted energy -*
*- predicted codebook gain => gcode0[exp_gcode0] -*
*---------------------------------------------------*/
gcode0 = Gainpred.gain_predict(past_qua_en, code, l_subfr);
/*-- pre-selection --*/
tmp = -1.0f / (4.0f * g_coeff[0] * g_coeff[2] - g_coeff[4] * g_coeff[4]);
best_gain[0] = (2.0f * g_coeff[2] * g_coeff[1] - g_coeff[3] * g_coeff[4]) * tmp;
best_gain[1] = (2.0f * 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 - *
*----------------------------------------------*/
var cand1Ref = new IntReference();
var cand2Ref = new IntReference();
gbk_presel(best_gain, cand1Ref, cand2Ref, gcode0);
cand1 = cand1Ref.value;
cand2 = cand2Ref.value;
/*-- selection --*/
dist_min = FLT_MAX_G729;
if (tameflag == 1)
{
for (i = 0; i < NCAN1; i++)
{
for (j = 0; j < NCAN2; j++)
{
g_pitch = gbk1[cand1 + i][0] + gbk2[cand2 + j][0];
if (g_pitch < GP0999)
{
g_code = gcode0 * (gbk1[cand1 + i][1] + gbk2[cand2 + j][1]);
dist = g_pitch * g_pitch * g_coeff[0]
+ g_pitch * g_coeff[1]
+ g_code * g_code * g_coeff[2]
+ g_code * g_coeff[3]
+ g_pitch * g_code * g_coeff[4];
if (dist < dist_min)
{
dist_min = dist;
index1 = cand1 + i;
index2 = cand2 + j;
}
}
}
}
}
else
{
for (i = 0; i < NCAN1; i++)
{
for (j = 0; j < NCAN2; j++)
{
g_pitch = gbk1[cand1 + i][0] + gbk2[cand2 + j][0];
g_code = gcode0 * (gbk1[cand1 + i][1] + gbk2[cand2 + j][1]);
dist = g_pitch * g_pitch * g_coeff[0]
+ g_pitch * g_coeff[1]
+ g_code * g_code * g_coeff[2]
+ g_code * g_coeff[3]
+ g_pitch * g_code * g_coeff[4];
if (dist < dist_min)
{
dist_min = dist;
index1 = cand1 + i;
index2 = cand2 + j;
}
}
}
}
gain_pit.value = gbk1[index1][0] + gbk2[index2][0];
g_code = gbk1[index1][1] + gbk2[index2][1];
gain_code.value = g_code * gcode0;
/*----------------------------------------------*
* update table of past quantized energies *
*----------------------------------------------*/
Gainpred.gain_update(past_qua_en, g_code);
return(map1[index1] * NCODE2 + map2[index2]);
}
/**
* Decode the adaptive and fixed codebook gains.
*
* @param index input : quantizer index
* @param code input : fixed code book vector
* @param l_subfr input : subframe size
* @param bfi input : bad frame indicator good = 0
* @param gain_pit output: quantized acb gain
* @param gain_code output: quantized fcb gain
*/
public void dec_gain(
int index,
float[] code,
int l_subfr,
int bfi,
FloatReference gain_pit,
FloatReference gain_code
)
{
var NCODE2 = Ld8k.NCODE2;
var gbk1 = TabLd8k.gbk1;
var gbk2 = TabLd8k.gbk2;
var imap1 = TabLd8k.imap1;
var imap2 = TabLd8k.imap2;
int index1, index2;
float gcode0, g_code;
/*----------------- Test erasure ---------------*/
if (bfi != 0)
{
gain_pit.value *= 0.9f;
if (gain_pit.value > 0.9f)
{
gain_pit.value = 0.9f;
}
gain_code.value *= 0.98f;
/*----------------------------------------------*
* update table of past quantized energies *
* (frame erasure) *
*----------------------------------------------*/
Gainpred.gain_update_erasure(past_qua_en);
return;
}
/*-------------- Decode pitch gain ---------------*/
index1 = imap1[index / NCODE2];
index2 = imap2[index % NCODE2];
gain_pit.value = gbk1[index1][0] + gbk2[index2][0];
/*-------------- Decode codebook gain ---------------*/
/*---------------------------------------------------*
*- energy due to innovation -*
*- predicted energy -*
*- predicted codebook gain => gcode0[exp_gcode0] -*
*---------------------------------------------------*/
gcode0 = Gainpred.gain_predict(past_qua_en, code, l_subfr);
/*-----------------------------------------------------------------*
* *gain_code = (gbk1[indice1][1]+gbk2[indice2][1]) * gcode0; *
*-----------------------------------------------------------------*/
g_code = gbk1[index1][1] + gbk2[index2][1];
gain_code.value = g_code * gcode0;
/*----------------------------------------------*
* update table of past quantized energies *
*----------------------------------------------*/
Gainpred.gain_update(past_qua_en, g_code);
}
