mus_dtct.c

语音编码G.729 语音编码G.729

/*
   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
*/


/* ----------------------------------------------------------------- */
/*                        MUSIC DETECTION MODULE                     */
/*                                                                   */
/*                                                                   */
/*                 (C) Copyright 1999 : Conexant Systems             */
/*                                                                   */
/* ----------------------------------------------------------------- */

/*
 File : MUS_DTCT.C
*/


#include <stdio.h>
#include <stdlib.h>
#include <math.h>
#include "typedef.h"
#include "ld8k.h"
#include "tab_ld8k.h"
#include "ld8cp.h"
#include "vad.h"


#define         sqr(a)          ((a)*(a))

void init_musdetect(struct musdet_state_t *state)
{
    state->count_music = 0;
    state->Mcount_music = (F)0.0;
    state->count_consc = 0;
    state->MeanPgain = (F)0.5;
    
    state->count_pflag = 0;
    state->Mcount_pflag = (F)0.0;
    state->count_consc_pflag = 0;
    state->count_consc_rflag = 0;
	set_zero(state->mrc, 10);
	state->MeanSE = (F)0.0;
}

void musdetect(
	struct musdet_state_t *state,
	int rate,
	FLOAT Energy,
	FLOAT *rc,
	int *lags,
	FLOAT *pgains,
	int stat_flg,
	int frm_count,
	int prev_vad,
	int *Vad,
	FLOAT LLenergy
)
{
    int i;
    FLOAT sum1, sum2,std;
    short PFLAG1, PFLAG2, PFLAG;
    
    FLOAT pderr, Lenergy , SD, tmp_vec[10];
    FLOAT Thres;
    
    pderr =(F)1.0;
    for (i=0; i< 4; i++) pderr *= ((F)1.0 - rc[i]*rc[i]);
    dvsub(state->mrc, rc, tmp_vec, 10);
    SD = dvdot(tmp_vec, tmp_vec, 10);
    
    Lenergy = (F)10.0*(FLOAT)log10(pderr*Energy/(F)240.0 +EPSI);
    
    if( *Vad == NOISE ){
        dvwadd(state->mrc, (F)0.9, rc, (F)0.1, state->mrc, 10);
        state->MeanSE = (F)0.9 * state->MeanSE + (F)0.1 * Lenergy;
    }
    
    sum1 =(F)0.0;
    sum2 =(F)0.0;
    for(i=0; i<5; i++){
        sum1 += (FLOAT) lags[i];
        sum2 +=  pgains[i];
    }
    
    sum1 = sum1/(F)5.0;
    sum2 = sum2/(F)5.0;
    std =(F)0.0;
    for(i=0; i<5; i++) std += sqr(((FLOAT) lags[i] - sum1));
    std = (FLOAT)sqrt(std/(F)4.0);
    
    state->MeanPgain = (F)0.8 * state->MeanPgain + (F)0.2*sum2;
    
    if (rate == G729D)
        Thres = (F)0.73;
    else
        Thres = (F)0.63;
    
    if (state->MeanPgain > Thres)
        PFLAG2 =1;
    else
        PFLAG2 =0;
    
    if (std < (F)1.30 && state->MeanPgain > (F)0.45)
        PFLAG1 =1;
    else
        PFLAG1 =0;
    
    PFLAG= (INT16)( ((INT16)prev_vad & (INT16)(PFLAG1 | PFLAG2))| (INT16)(PFLAG2));
    
    if(rc[1] <= (F)0.45 && rc[1] >= (F)0.0 && state->MeanPgain < (F)0.5)
        state->count_consc_rflag++;
    else
        state->count_consc_rflag = 0;
    
    if (stat_flg == 1 && (*Vad == VOICE))
        state->count_music++;
    
    if ((frm_count%64) == 0 ){
        if( frm_count == 64)
            state->Mcount_music = (FLOAT)state->count_music;
        else
            state->Mcount_music = (F)0.9 * state->Mcount_music + (F)0.1 * (FLOAT)state->count_music;
    }
    
    if (state->count_music == 0)
        state->count_consc++;
    else
        state->count_consc = 0;
    
    if(state->count_consc > 500 || state->count_consc_rflag > 150)
		state->Mcount_music = (F)0.0;
    
    if ((frm_count%64) == 0)
        state->count_music = 0;
    
    if (PFLAG == 1 )
        state->count_pflag++;
    
    if ((frm_count%64) == 0){
        if (frm_count == 64)
            state->Mcount_pflag = (FLOAT)state->count_pflag;
        else {
            if (state->count_pflag > 25)
                state->Mcount_pflag = (F)0.98 * state->Mcount_pflag + (F)0.02*(FLOAT)state->count_pflag;
            else if (state->count_pflag > 20)
                state->Mcount_pflag = (F)0.95 * state->Mcount_pflag + (F)0.05*(FLOAT)state->count_pflag;
            else
                state->Mcount_pflag = (F)0.90 * state->Mcount_pflag + (F)0.10*(FLOAT)state->count_pflag;
        }
    }
    
    if (state->count_pflag == 0)
        state->count_consc_pflag++;
    else
        state->count_consc_pflag = 0;
    
    if (state->count_consc_pflag > 100 || state->count_consc_rflag > 150) state->Mcount_pflag = (F)0.0;
    
    if ((frm_count%64) == 0)
        state->count_pflag = 0;
    
    if (rate == G729E){
        if (SD > (F)0.15 && (Lenergy - state->MeanSE) > (F)4.0 && (LLenergy > 50.0))
            *Vad = VOICE;
        else if ((SD > (F)0.38 || (Lenergy - state->MeanSE)> (F)4.0) && (LLenergy > 50.0))
            *Vad = VOICE;
        else if ((state->Mcount_pflag >= (F)10.0 || state->Mcount_music >= (F)5.0 || frm_count < 64)
            && (LLenergy > 7.0))
            *Vad = VOICE;
    }
}