/*

ITU-T G.729A Annex B ANSI-C Source Code

Version 1.3 Last modified: August 1997

Copyright (c) 1996, France Telecom, Rockwell International,

Universite de Sherbrooke.

All rights reserved.

*/

#include <stdio.h>

#include "typedef.h"

#include "ld8a.h"

#include "basic_op.h"

#include "oper_32b.h"

#include "tab_ld8a.h"

#include "vad.h"

#include "dtx.h"

#include "tab_dtx.h"

/* local function */

static Word16 MakeDec(

);

/* static variables */

static Word16 MeanLSF[M];

static Word16 Min_buffer[16];

static Word16 Prev_Min, Next_Min, Min;

static Word16 MeanE, MeanSE, MeanSLE, MeanSZC;

static Word16 prev_energy;

static Word16 count_sil, count_update, count_ext;

static Word16 flag, v_flag, less_count;

/*---------------------------------------------------------------------------*

* Function vad_init *

* ~~~~~~~~~~~~~~~~~~ *

* *

* -> Initialization of variables for voice activity detection *

* *

*---------------------------------------------------------------------------*/

void vad_init(void)

{

/* Static vectors to zero */

Set_zero(MeanLSF, M);

/* Initialize VAD parameters */

MeanSE = 0;

MeanSLE = 0;

MeanE = 0;

MeanSZC = 0;

count_sil = 0;

count_update = 0;

count_ext = 0;

less_count = 0;

flag = 1;

Min = MAX_16;

}

/*-----------------------------------------------------------------*

* Functions vad *

* ~~~ *

* Input: *

* rc : reflection coefficient *

* lsf[] : unquantized lsf vector *

* r_h[] : upper 16-bits of the autocorrelation vector *

* r_l[] : lower 16-bits of the autocorrelation vector *

* exp_R0 : exponent of the autocorrelation vector *

* sigpp[] : preprocessed input signal *

* frm_count : frame counter *

* prev_marker : VAD decision of the last frame *

* pprev_marker : VAD decision of the frame before last frame *

* *

* Output: *

* *

* marker : VAD decision of the current frame *

* *

*-----------------------------------------------------------------*/

void vad(

Word16 *marker)

{

/* scalar */

Word32 acc0;

Word16 i, j, exp, frac;

Word16 ENERGY, ENERGY_low, SD, ZC, dSE, dSLE, dSZC;

Word16 COEF, C_COEF, COEFZC, C_COEFZC, COEFSD, C_COEFSD;

/* compute the frame energy */

acc0 = L_Comp(r_h[0], r_l[0]);

Log2(acc0, &exp, &frac);

acc0 = Mpy_32_16(exp, frac, 9864);

i = sub(exp_R0, 1);

i = sub(i, 1);

acc0 = L_mac(acc0, 9864, i);

acc0 = L_shl(acc0, 11);

ENERGY = extract_h(acc0);

ENERGY = sub(ENERGY, 4875);

/* compute the low band energy */

acc0 = 0;

for (i=1; i<=NP; i++)

acc0 = L_mac(acc0, r_h[i], lbf_corr[i]);

acc0 = L_shl(acc0, 1);

acc0 = L_mac(acc0, r_h[0], lbf_corr[0]);

Log2(acc0, &exp, &frac);

acc0 = Mpy_32_16(exp, frac, 9864);

i = sub(exp_R0, 1);

i = sub(i, 1);

acc0 = L_mac(acc0, 9864, i);

acc0 = L_shl(acc0, 11);

ENERGY_low = extract_h(acc0);

ENERGY_low = sub(ENERGY_low, 4875);

/* compute SD */

acc0 = 0;

for (i=0; i<M; i++){

j = sub(lsf[i], MeanLSF[i]);

acc0 = L_mac(acc0, j, j);

}

SD = extract_h(acc0); /* Q15 */

/* compute # zero crossing */

ZC = 0;

for (i=ZC_START+1; i<=ZC_END; i++)

if (mult(sigpp[i-1], sigpp[i]) < 0)

ZC = add(ZC, 410); /* Q15 */

/* Initialize and update Mins */

if(sub(frm_count, 129) < 0){

if (sub(ENERGY, Min) < 0){

Min = ENERGY;

Prev_Min = ENERGY;

}

if((frm_count & 0x0007) == 0){

i = sub(shr(frm_count,3),1);

Min_buffer[i] = Min;

Min = MAX_16;

}

}

if((frm_count & 0x0007) == 0){

Prev_Min = Min_buffer[0];

for (i=1; i<16; i++){

if (sub(Min_buffer[i], Prev_Min) < 0)

Prev_Min = Min_buffer[i];

}

}

if(sub(frm_count, 129) >= 0){

if(((frm_count & 0x0007) ^ (0x0001)) == 0){

Min = Prev_Min;

Next_Min = MAX_16;

}

if (sub(ENERGY, Min) < 0)

Min = ENERGY;

if (sub(ENERGY, Next_Min) < 0)

Next_Min = ENERGY;

if((frm_count & 0x0007) == 0){

for (i=0; i<15; i++)

Min_buffer[i] = Min_buffer[i+1];

Min_buffer[15] = Next_Min;

Prev_Min = Min_buffer[0];

for (i=1; i<16; i++)

if (sub(Min_buffer[i], Prev_Min) < 0)

Prev_Min = Min_buffer[i];

}

}

if (sub(frm_count, INIT_FRAME) <= 0)

if(sub(ENERGY, 3072) < 0){

*marker = NOISE;

less_count++;

}

else{

*marker = VOICE;

acc0 = L_deposit_h(MeanE);

acc0 = L_mac(acc0, ENERGY, 1024);

MeanE = extract_h(acc0);

acc0 = L_deposit_h(MeanSZC);

acc0 = L_mac(acc0, ZC, 1024);

MeanSZC = extract_h(acc0);

for (i=0; i<M; i++){

acc0 = L_deposit_h(MeanLSF[i]);

acc0 = L_mac(acc0, lsf[i], 1024);

MeanLSF[i] = extract_h(acc0);

}

}

if (sub(frm_count, INIT_FRAME) >= 0){

if (sub(frm_count, INIT_FRAME) == 0){

acc0 = L_mult(MeanE, factor_fx[less_count]);

acc0 = L_shl(acc0, shift_fx[less_count]);

MeanE = extract_h(acc0);

acc0 = L_mult(MeanSZC, factor_fx[less_count]);

acc0 = L_shl(acc0, shift_fx[less_count]);

MeanSZC = extract_h(acc0);

for (i=0; i<M; i++){

acc0 = L_mult(MeanLSF[i], factor_fx[less_count]);

acc0 = L_shl(acc0, shift_fx[less_count]);

MeanLSF[i] = extract_h(acc0);

}

MeanSE = sub(MeanE, 2048); /* Q11 */

MeanSLE = sub(MeanE, 2458); /* Q11 */

}

dSE = sub(MeanSE, ENERGY);

dSLE = sub(MeanSLE, ENERGY_low);

dSZC = sub(MeanSZC, ZC);

if(sub(ENERGY, 3072) < 0)

*marker = NOISE;

else

*marker = MakeDec(dSLE, dSE, SD, dSZC);

v_flag = 0;

if((prev_marker==VOICE) && (*marker==NOISE) && (add(dSE,410) < 0)

&& (sub(ENERGY, 3072)>0)){

*marker = VOICE;

v_flag = 1;

}

if(flag == 1){

if((pprev_marker == VOICE) &&

(prev_marker == VOICE) &&

(*marker == NOISE) &&

(sub(abs_s(sub(prev_energy,ENERGY)), 614) <= 0)){

count_ext++;

*marker = VOICE;

v_flag = 1;

if(sub(count_ext, 4) <= 0)

flag=1;

else{

count_ext=0;

flag=0;

}

}

}

else

flag=1;

if(*marker == NOISE)

count_sil++;

if((*marker == VOICE) && (sub(count_sil, 10) > 0) &&

(sub(sub(ENERGY,prev_energy), 614) <= 0)){

*marker = NOISE;

count_sil=0;

}

if(*marker == VOICE)

count_sil=0;

if ((sub(sub(ENERGY, 614), MeanSE) < 0) && (sub(frm_count, 128) > 0)

&& (!v_flag) && (sub(rc, 19661) < 0))

*marker = NOISE;

if ((sub(sub(ENERGY,614),MeanSE) < 0) && (sub(rc, 24576) < 0)

&& (sub(SD, 83) < 0)){

count_update++;

if (sub(count_update, INIT_COUNT) < 0){

COEF = 24576;

C_COEF = 8192;

COEFZC = 26214;

C_COEFZC = 6554;

COEFSD = 19661;

C_COEFSD = 13017;

}

else

if (sub(count_update, INIT_COUNT+10) < 0){

COEF = 31130;

C_COEF = 1638;

COEFZC = 30147;

C_COEFZC = 2621;

COEFSD = 21299;

C_COEFSD = 11469;

}

else

if (sub(count_update, INIT_COUNT+20) < 0){

COEF = 31785;

C_COEF = 983;

COEFZC = 30802;

C_COEFZC = 1966;

COEFSD = 22938;

C_COEFSD = 9830;

}

else

if (sub(count_update, INIT_COUNT+30) < 0){

COEF = 32440;

C_COEF = 328;

COEFZC = 31457;

C_COEFZC = 1311;

COEFSD = 24576;

C_COEFSD = 8192;

}

else

if (sub(count_update, INIT_COUNT+40) < 0){

COEF = 32604;

C_COEF = 164;

COEFZC = 32440;

C_COEFZC = 328;

COEFSD = 24576;

C_COEFSD = 8192;

}

else{

COEF = 32604;

C_COEF = 164;

COEFZC = 32702;

C_COEFZC = 66;

COEFSD = 24576;

C_COEFSD = 8192;

}

/* compute MeanSE */

acc0 = L_mult(COEF, MeanSE);

acc0 = L_mac(acc0, C_COEF, ENERGY);

MeanSE = extract_h(acc0);

/* compute MeanSLE */

acc0 = L_mult(COEF, MeanSLE);

acc0 = L_mac(acc0, C_COEF, ENERGY_low);

MeanSLE = extract_h(acc0);

/* compute MeanSZC */

acc0 = L_mult(COEFZC, MeanSZC);

acc0 = L_mac(acc0, C_COEFZC, ZC);

MeanSZC = extract_h(acc0);

/* compute MeanLSF */

for (i=0; i<M; i++){

acc0 = L_mult(COEFSD, MeanLSF[i]);

acc0 = L_mac(acc0, C_COEFSD, lsf[i]);

MeanLSF[i] = extract_h(acc0);

}

}

if((sub(frm_count, 128) > 0) && (((sub(MeanSE,Min) < 0) &&

(sub(SD, 83) < 0)) || (sub(MeanSE,Min) > 2048))){

MeanSE = Min;

count_update = 0;

}

}

prev_energy = ENERGY;

}

/* local function */

static Word16 MakeDec(

)

{

Word32 acc0;

/* SD vs dSZC */

acc0 = L_mult(dSZC, -14680); /* Q15*Q23*2 = Q39 */

acc0 = L_mac(acc0, 8192, -28521); /* Q15*Q23*2 = Q39 */

acc0 = L_shr(acc0, 8); /* Q39 -> Q31 */

acc0 = L_add(acc0, L_deposit_h(SD));

if (acc0 > 0) return(VOICE);

acc0 = L_mult(dSZC, 19065); /* Q15*Q22*2 = Q38 */

acc0 = L_mac(acc0, 8192, -19446); /* Q15*Q22*2 = Q38 */

acc0 = L_shr(acc0, 7); /* Q38 -> Q31 */

acc0 = L_add(acc0, L_deposit_h(SD));

if (acc0 > 0) return(VOICE);

/* dSE vs dSZC */

acc0 = L_mult(dSZC, 20480); /* Q15*Q13*2 = Q29 */

acc0 = L_mac(acc0, 8192, 16384); /* Q13*Q15*2 = Q29 */

acc0 = L_shr(acc0, 2); /* Q29 -> Q27 */

acc0 = L_add(acc0, L_deposit_h(dSE));

if (acc0 < 0) return(VOICE);

acc0 = L_mult(dSZC, -16384); /* Q15*Q13*2 = Q29 */

acc0 = L_mac(acc0, 8192, 19660); /* Q13*Q15*2 = Q29 */

acc0 = L_shr(acc0, 2); /* Q29 -> Q27 */

acc0 = L_add(acc0, L_deposit_h(dSE));

if (acc0 < 0) return(VOICE);

acc0 = L_mult(dSE, 32767); /* Q11*Q15*2 = Q27 */

acc0 = L_mac(acc0, 1024, 30802); /* Q10*Q16*2 = Q27 */

if (acc0 < 0) return(VOICE);

/* dSE vs SD */

acc0 = L_mult(SD, -28160); /* Q15*Q5*2 = Q22 */

acc0 = L_mac(acc0, 64, 19988); /* Q6*Q14*2 = Q22 */

acc0 = L_mac(acc0, dSE, 512); /* Q11*Q9*2 = Q22 */

if (acc0 < 0) return(VOICE);

acc0 = L_mult(SD, 32767); /* Q15*Q15*2 = Q31 */

acc0 = L_mac(acc0, 32, -30199); /* Q5*Q25*2 = Q31 */

if (acc0 > 0) return(VOICE);

/* dSLE vs dSZC */

acc0 = L_mult(dSZC, -20480); /* Q15*Q13*2 = Q29 */

acc0 = L_mac(acc0, 8192, 22938); /* Q13*Q15*2 = Q29 */

acc0 = L_shr(acc0, 2); /* Q29 -> Q27 */

acc0 = L_add(acc0, L_deposit_h(dSE));

if (acc0 < 0) return(VOICE);

acc0 = L_mult(dSZC, 23831); /* Q15*Q13*2 = Q29 */

acc0 = L_mac(acc0, 4096, 31576); /* Q12*Q16*2 = Q29 */

acc0 = L_shr(acc0, 2); /* Q29 -> Q27 */

acc0 = L_add(acc0, L_deposit_h(dSE));

if (acc0 < 0) return(VOICE);

acc0 = L_mult(dSE, 32767); /* Q11*Q15*2 = Q27 */

acc0 = L_mac(acc0, 2048, 17367); /* Q11*Q15*2 = Q27 */

if (acc0 < 0) return(VOICE);

/* dSLE vs SD */

acc0 = L_mult(SD, -22400); /* Q15*Q4*2 = Q20 */

acc0 = L_mac(acc0, 32, 25395); /* Q5*Q14*2 = Q20 */

acc0 = L_mac(acc0, dSLE, 256); /* Q11*Q8*2 = Q20 */

if (acc0 < 0) return(VOICE);

/* dSLE vs dSE */

acc0 = L_mult(dSE, -30427); /* Q11*Q15*2 = Q27 */

acc0 = L_mac(acc0, 256, -29959); /* Q8*Q18*2 = Q27 */

acc0 = L_add(acc0, L_deposit_h(dSLE));

if (acc0 > 0) return(VOICE);

acc0 = L_mult(dSE, -23406); /* Q11*Q15*2 = Q27 */

acc0 = L_mac(acc0, 512, 28087); /* Q19*Q17*2 = Q27 */

acc0 = L_add(acc0, L_deposit_h(dSLE));

if (acc0 < 0) return(VOICE);

acc0 = L_mult(dSE, 24576); /* Q11*Q14*2 = Q26 */

acc0 = L_mac(acc0, 1024, 29491); /* Q10*Q15*2 = Q26 */

acc0 = L_mac(acc0, dSLE, 16384); /* Q11*Q14*2 = Q26 */

if (acc0 < 0) return(VOICE);

return (NOISE);

}