最近把opus编码器里的VAD算法提取了出来，之前在网上没找到合适的开源VAD模块，就把代码放在这里吧，希望能帮助到人。

下面是.h文件和.cpp文件，使用的时候，需要调用silk_VAD_Get()这个函数，每次输入一个帧(我默认了帧长是20ms，采样率16khz，可以自己在silk_VAD_Get里修改)，返回0或者1，代表该帧是否为静音帧。

.h文件代码：

#include

#include

#include

#include

int silk_VAD_Get(

//int state, /* Encoder state */

const short pIn[] /* I PCM input */

);

#define TYPE_NO_VOICE_ACTIVITY 0

#define TYPE_UNVOICED 1

#define TYPE_VOICED 2

#define SPEECH_ACTIVITY_DTX_THRES 0.05f

#define SILK_FIX_CONST( C, Q ) ((int)((C) * ((long)1 << (Q)) + 0.5))

#define silk_int16_MAX 0x7FFF /* 2^15 - 1 = 32767 */

#define silk_int16_MIN ((short)0x8000) /* -2^15 = -32768 */

#define silk_int32_MAX 0x7FFFFFFF /* 2^31 - 1 = 2147483647 */

#define silk_int32_MIN ((int)0x80000000) /* -2^31 = -2147483648 */

#define silk_memset(dest, src, size) memset((dest), (src), (size))

#define VAD_NOISE_LEVEL_SMOOTH_COEF_Q16 1024 /* Must be < 4096 */

#define VAD_NOISE_LEVELS_BIAS 50

/* Sigmoid settings */

#define VAD_NEGATIVE_OFFSET_Q5 128 /* sigmoid is 0 at -128 */

#define VAD_SNR_FACTOR_Q16 45000

/* smoothing for SNR measurement */

#define VAD_SNR_SMOOTH_COEF_Q18 4096

#define VAD_N_BANDS 4

#define VAD_INTERNAL_SUBFRAMES_LOG2 2

#define VAD_INTERNAL_SUBFRAMES ( 1 << VAD_INTERNAL_SUBFRAMES_LOG2 )

#define silk_uint8_MAX 0xFF /* 2^8 - 1 = 255 */

#define VARDECL(type, var) type *var

#define silk_RSHIFT32(a, shift) ((a)>>(shift))

#define silk_RSHIFT(a, shift) ((a)>>(shift))

#define silk_LSHIFT32(a, shift) ((a)<

#define silk_LSHIFT(a, shift) ((a)<

#define ALLOC(var, size, type) var = ((type*)alloca(sizeof(type)*(size)))

#define silk_ADD16(a, b) ((a) + (b))

#define silk_ADD32(a, b) ((a) + (b))

#define silk_ADD64(a, b) ((a) + (b))

#define silk_SUB16(a, b) ((a) - (b))

#define silk_SUB32(a, b) ((a) - (b))

#define silk_SUB64(a, b) ((a) - (b))

#define silk_SMULWB(a32, b32) ((((a32) >> 16) * (int)((short)(b32))) + ((((a32) & 0x0000FFFF) * (int)((short)(b32))) >> 16))

#define silk_SMLAWB(a32, b32, c32) ((a32) + ((((b32) >> 16) * (int)((short)(c32))) + ((((b32) & 0x0000FFFF) * (int)((short)(c32))) >> 16)))

#define silk_SAT16(a) ((a) > silk_int16_MAX ? silk_int16_MAX : \

((a) < silk_int16_MIN ? silk_int16_MIN : (a)))

#define silk_MLA(a32, b32, c32) silk_ADD32((a32),((b32) * (c32)))

#define silk_SMLABB(a32, b32, c32) ((a32) + ((int)((short)(b32))) * (int)((short)(c32)))

#define silk_ADD_POS_SAT32(a, b) ((((unsigned int)(a)+(unsigned int)(b)) & 0x80000000) ? silk_int32_MAX : ((a)+(b)))

#define silk_ADD_POS_SAT32(a, b) ((((unsigned int)(a)+(unsigned int)(b)) & 0x80000000) ? silk_int32_MAX : ((a)+(b)))

#define silk_DIV32_16(a32, b16) ((int)((a32) / (b16)))

#define silk_DIV32(a32, b32) ((int)((a32) / (b32)))

#define silk_RSHIFT_ROUND(a, shift) ((shift) == 1 ? ((a) >> 1) + ((a) & 1) : (((a) >> ((shift) - 1)) + 1) >> 1)

#define silk_SMULWW(a32, b32) silk_MLA(silk_SMULWB((a32), (b32)), (a32), silk_RSHIFT_ROUND((b32), 16))

#define silk_min(a, b) (((a) < (b)) ? (a) : (b))

#define silk_max(a, b) (((a) > (b)) ? (a) : (b))

#define silk_ADD_LSHIFT32(a, b, shift) silk_ADD32((a), silk_LSHIFT32((b), (shift))) /* shift >= 0 */

#define silk_MUL(a32, b32) ((a32) * (b32))

#define silk_SMULBB(a32, b32) ((int)((short)(a32)) * (int)((short)(b32)))

#define silk_LIMIT( a, limit1, limit2) ((limit1) > (limit2) ? ((a) > (limit1) ? (limit1) : ((a) < (limit2) ? (limit2) : (a))) \

: ((a) > (limit2) ? (limit2) : ((a) < (limit1) ? (limit1) : (a))))

#define silk_LSHIFT_SAT32(a, shift) (silk_LSHIFT32( silk_LIMIT( (a), silk_RSHIFT32( silk_int32_MIN, (shift) ), \

silk_RSHIFT32( silk_int32_MAX, (shift) ) ), (shift) ))

static const int tiltWeights[VAD_N_BANDS] = { 30000, 6000, -12000, -12000 };

static const int sigm_LUT_neg_Q15[6] = {

16384, 8812, 3906, 1554, 589, 219

};

static const int sigm_LUT_slope_Q10[6] = {

237, 153, 73, 30, 12, 7

};

static const int sigm_LUT_pos_Q15[6] = {

16384, 23955, 28861, 31213, 32178, 32548

};

static __inline int ec_bsr(unsigned long _x) {

unsigned long ret;

_BitScanReverse(&ret, _x);

return (int)ret;

}

# define EC_CLZ0 (1)

# define EC_CLZ(_x) (-ec_bsr(_x))

# define EC_ILOG(_x) (EC_CLZ0-EC_CLZ(_x))

static int silk_min_int(int a, int b)

{

return (((a) < (b)) ? (a) : (b));

}

static int silk_max_int(int a, int b)

{

return (((a) > (b)) ? (a) : (b));

}

static int silk_max_32(int a, int b)

{

return (((a) > (b)) ? (a) : (b));

}

static int silk_CLZ32(int in32)

{

return in32 ? 32 - EC_ILOG(in32) : 32;

}

static int silk_ROR32(int a32, int rot)

{

unsigned int x = (unsigned int)a32;

unsigned int r = (unsigned int)rot;

unsigned int m = (unsigned int)-rot;

if (rot == 0) {

return a32;

}

else if (rot < 0) {

return (int)((x << m) | (x >> (32 - m)));

}

else {

return (int)((x << (32 - r)) | (x >> r));

}

}

static void silk_CLZ_FRAC(

int in, /* I input */

int *lz, /* O number of leading zeros */

int *frac_Q7 /* O the 7 bits right after the leading one */

)

{

int lzeros = silk_CLZ32(in);

*lz = lzeros;

*frac_Q7 = silk_ROR32(in, 24 - lzeros) & 0x7f;

}

/* Approximation of square root */

/* Accuracy: < +/- 10% for output values > 15 */

/* < +/- 2.5% for output values > 120 */

static int silk_SQRT_APPROX(int x)

{

int y, lz, frac_Q7;

if (x <= 0) {

return 0;

}

silk_CLZ_FRAC(x, &lz, &frac_Q7);

if (lz & 1) {

y = 32768;

}

else {

y = 46214; /* 46214 = sqrt(2) * 32768 */

}

/* get scaling right */

y >>= silk_RSHIFT(lz, 1);

/* increment using fractional part of input */

y = silk_SMLAWB(y, y, silk_SMULBB(213, frac_Q7));

return y;

}

.cpp文件代码：

#include "opusvad.h"

#include

static short A_fb1_20 = 5394 << 1;

static short A_fb1_21 = -24290; /* (int16)(20623 << 1) */

typedef struct {

int AnaState[2]; /* Analysis filterbank state: 0-8 kHz */

int AnaState1[2]; /* Analysis filterbank state: 0-4 kHz */

int AnaState2[2]; /* Analysis filterbank state: 0-2 kHz */

int XnrgSubfr[4]; /* Subframe energies */

int NrgRatioSmth_Q8[VAD_N_BANDS]; /* Smoothed energy level in each band */

short HPstate; /* State of differentiator in the lowest band */

int NL[VAD_N_BANDS]; /* Noise energy level in each band */

int inv_NL[VAD_N_BANDS]; /* Inverse noise energy level in each band */

int NoiseLevelBias[VAD_N_BANDS]; /* Noise level estimator bias/offset */

int counter; /* Frame counter used in the initial phase */

} VAD_state;

/* Split signal into two decimated bands using first-order allpass filters */

void silk_ana_filt_bank_1(

const short *in, /* I Input signal [N] */

int *S, /* I/O State vector [2] */

short *outL, /* O Low band [N/2] */

short *outH, /* O High band [N/2] */

const int N /* I Number of input samples */

)

{

int k, N2 = silk_RSHIFT(N, 1);

int in32, X, Y, out_1, out_2;

/* Internal variables and state are in Q10 format */

for (k = 0; k < N2; k++) {

/* Convert to Q10 */

in32 = silk_LSHIFT((int)in[2 * k], 10);

/* All-pass section for even input sample */

Y = silk_SUB32(in32, S[0]);

X = silk_SMLAWB(Y, Y, A_fb1_21);

out_1 = silk_ADD32(S[0], X);

S[0] = silk_ADD32(in32, X);

/* Convert to Q10 */

in32 = silk_LSHIFT((int)in[2 * k + 1], 10);

/* All-pass section for odd input sample, and add to output of previous section */

Y = silk_SUB32(in32, S[1]);

X = silk_SMULWB(Y, A_fb1_20);

out_2 = silk_ADD32(S[1], X);

S[1] = silk_ADD32(in32, X);

/* Add/subtract, convert back to int16 and store to output */

outL[k] = (short)silk_SAT16(silk_RSHIFT_ROUND(silk_ADD32(out_2, out_1), 11));

outH[k] = (short)silk_SAT16(silk_RSHIFT_ROUND(silk_SUB32(out_2, out_1), 11));

}

}

void silk_VAD_GetNoiseLevels(

const int pX[VAD_N_BANDS], /* I subband energies */

VAD_state *psSilk_VAD /* I/O Pointer to Silk VAD state */

)

{

int k;

int nl, nrg, inv_nrg;

int coef, min_coef;

/* Initially faster smoothing */

if (psSilk_VAD->counter < 1000) { /* 1000 = 20 sec */

min_coef = silk_DIV32_16(silk_int16_MAX, silk_RSHIFT(psSilk_VAD->counter, 4) + 1);

}

else {

min_coef = 0;

}

for (k = 0; k < VAD_N_BANDS; k++) {

/* Get old noise level estimate for current band */

nl = psSilk_VAD->NL[k];

//silk_assert(nl >= 0);

/* Add bias */

nrg = silk_ADD_POS_SAT32(pX[k], psSilk_VAD->NoiseLevelBias[k]);

//silk_assert(nrg > 0);

/* Invert energies */

inv_nrg = silk_DIV32(silk_int32_MAX, nrg);

//silk_assert(inv_nrg >= 0);

/* Less update when subband energy is high */

if (nrg > silk_LSHIFT(nl, 3)) {

coef = VAD_NOISE_LEVEL_SMOOTH_COEF_Q16 >> 3;

}

else if (nrg < nl) {

coef = VAD_NOISE_LEVEL_SMOOTH_COEF_Q16;

}

else {

coef = silk_SMULWB(silk_SMULWW(inv_nrg, nl), VAD_NOISE_LEVEL_SMOOTH_COEF_Q16 << 1);

}

/* Initially faster smoothing */

coef = silk_max_int(coef, min_coef);

/* Smooth inverse energies */

psSilk_VAD->inv_NL[k] = silk_SMLAWB(psSilk_VAD->inv_NL[k], inv_nrg - psSilk_VAD->inv_NL[k], coef);

//silk_assert(psSilk_VAD->inv_NL[k] >= 0);

/* Compute noise level by inverting again */

nl = silk_DIV32(silk_int32_MAX, psSilk_VAD->inv_NL[k]);

//silk_assert(nl >= 0);

/* Limit noise levels (guarantee 7 bits of head room) */

nl = silk_min(nl, 0x00FFFFFF);

/* Store as part of state */

psSilk_VAD->NL[k] = nl;

}

/* Increment frame counter */

psSilk_VAD->counter++;

}

int silk_lin2log(

const int inLin /* I input in linear scale */

)

{

int lz, frac_Q7;

silk_CLZ_FRAC(inLin, &lz, &frac_Q7);

/* Piece-wise parabolic approximation */

return silk_ADD_LSHIFT32(silk_SMLAWB(frac_Q7, silk_MUL(frac_Q7, 128 - frac_Q7), 179), 31 - lz, 7);

}

int silk_sigm_Q15(

int in_Q5 /* I */

)

{

int ind;

if (in_Q5 < 0) {

/* Negative input */

in_Q5 = -in_Q5;

if (in_Q5 >= 6 * 32) {

return 0; /* Clip */

}

else {

/* Linear interpolation of look up table */

ind = silk_RSHIFT(in_Q5, 5);

return(sigm_LUT_neg_Q15[ind] - silk_SMULBB(sigm_LUT_slope_Q10[ind], in_Q5 & 0x1F));

}

}

else {

/* Positive input */

if (in_Q5 >= 6 * 32) {

return 32767; /* clip */

}

else {

/* Linear interpolation of look up table */

ind = silk_RSHIFT(in_Q5, 5);

return(sigm_LUT_pos_Q15[ind] + silk_SMULBB(sigm_LUT_slope_Q10[ind], in_Q5 & 0x1F));

}

}

}

int silk_VAD_Init( /* O Return value, 0 if success */

VAD_state *psSilk_VAD /* I/O Pointer to Silk VAD state */

)

{

int b, ret = 0;

/* reset state memory */

silk_memset(psSilk_VAD, 0, sizeof(VAD_state));

/* init noise levels */

/* Initialize array with approx pink noise levels (psd proportional to inverse of frequency) */

for (b = 0; b < VAD_N_BANDS; b++) {

psSilk_VAD->NoiseLevelBias[b] = silk_max_32(silk_DIV32_16(VAD_NOISE_LEVELS_BIAS, b + 1), 1);

}

/* Initialize state */

for (b = 0; b < VAD_N_BANDS; b++) {

psSilk_VAD->NL[b] = silk_MUL(100, psSilk_VAD->NoiseLevelBias[b]);

psSilk_VAD->inv_NL[b] = silk_DIV32(silk_int32_MAX, psSilk_VAD->NL[b]);

}

psSilk_VAD->counter = 15;

/* init smoothed energy-to-noise ratio*/

for (b = 0; b < VAD_N_BANDS; b++) {

psSilk_VAD->NrgRatioSmth_Q8[b] = 100 * 256; /* 100 * 256 --> 20 dB SNR */

}

return(ret);

}

static int noSpeechCounter;

int silk_VAD_Get(

//int state, /* Encoder state */

const short pIn[] /* I PCM input */

)

{

int SA_Q15, pSNR_dB_Q7, input_tilt;

int decimated_framelength1, decimated_framelength2;

int decimated_framelength;

int dec_subframe_length, dec_subframe_offset, SNR_Q7, i, b, s;

int sumSquared, smooth_coef_Q16;

short HPstateTmp;

VARDECL(short, X);

int Xnrg[4];

int NrgToNoiseRatio_Q8[4];

int speech_nrg, x_tmp;

int X_offset[4];

int ret = 0;

int frame_length = 20;//

int fs_kHz = 16;

int input_quality_bands_Q15[VAD_N_BANDS];

int signalType;

int VAD_flag;

/* Safety checks

silk_assert(4 == 4);

silk_assert(MAX_FRAME_LENGTH >= frame_length);

silk_assert(frame_length <= 512);

silk_assert(frame_length == 8 * silk_RSHIFT(frame_length, 3));

*/

/***********************/

/* Filter and Decimate */

/***********************/

decimated_framelength1 = silk_RSHIFT(frame_length, 1);

decimated_framelength2 = silk_RSHIFT(frame_length, 2);

decimated_framelength = silk_RSHIFT(frame_length, 3);

/* Decimate into 4 bands:

0 L 3L L 3L 5L

- -- - -- --

8 8 2 4 4

[0-1 kHz| temp. |1-2 kHz| 2-4 kHz | 4-8 kHz |

They're arranged to allow the minimal ( frame_length / 4 ) extra

scratch space during the downsampling process */

X_offset[0] = 0;

X_offset[1] = decimated_framelength + decimated_framelength2;

X_offset[2] = X_offset[1] + decimated_framelength;

X_offset[3] = X_offset[2] + decimated_framelength2;

ALLOC(X, X_offset[3] + decimated_framelength1, short);

VAD_state *psSilk_VAD;

psSilk_VAD = (VAD_state*)malloc(sizeof(VAD_state));

int ret1 = silk_VAD_Init(psSilk_VAD);

/* 0-8 kHz to 0-4 kHz and 4-8 kHz */

silk_ana_filt_bank_1(pIn, &psSilk_VAD->AnaState[0],

X, &X[X_offset[3]], frame_length);

/* 0-4 kHz to 0-2 kHz and 2-4 kHz */

silk_ana_filt_bank_1(X, &psSilk_VAD->AnaState1[0],

X, &X[X_offset[2]], decimated_framelength1);

/* 0-2 kHz to 0-1 kHz and 1-2 kHz */

silk_ana_filt_bank_1(X, &psSilk_VAD->AnaState2[0],

X, &X[X_offset[1]], decimated_framelength2);

/*********************************************/

/* HP filter on lowest band (differentiator) */

/*********************************************/

X[decimated_framelength - 1] = silk_RSHIFT(X[decimated_framelength - 1], 1);

HPstateTmp = X[decimated_framelength - 1];

for (i = decimated_framelength - 1; i > 0; i--) {

X[i - 1] = silk_RSHIFT(X[i - 1], 1);

X[i] -= X[i - 1];

}

X[0] -= psSilk_VAD->HPstate;

psSilk_VAD->HPstate = HPstateTmp;

/*************************************/

/* Calculate the energy in each band */

/*************************************/

for (b = 0; b < 4; b++) {

/* Find the decimated framelength in the non-uniformly divided bands */

decimated_framelength = silk_RSHIFT(frame_length, silk_min_int(4 - b, 4 - 1));

/* Split length into subframe lengths */

dec_subframe_length = silk_RSHIFT(decimated_framelength, VAD_INTERNAL_SUBFRAMES_LOG2);

dec_subframe_offset = 0;

/* Compute energy per sub-frame */

/* initialize with summed energy of last subframe */

Xnrg[b] = psSilk_VAD->XnrgSubfr[b];

for (s = 0; s < VAD_INTERNAL_SUBFRAMES; s++) {

sumSquared = 0;

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

/* The energy will be less than dec_subframe_length * ( silk_short_MIN / 8 ) ^ 2. */

/* Therefore we can accumulate with no risk of overflow (unless dec_subframe_length > 128) */

x_tmp = silk_RSHIFT(

X[X_offset[b] + i + dec_subframe_offset], 3);

sumSquared = silk_SMLABB(sumSquared, x_tmp, x_tmp);

/* Safety check */

//silk_assert(sumSquared >= 0);

}

/* Add/saturate summed energy of current subframe */

if (s < VAD_INTERNAL_SUBFRAMES - 1) {

Xnrg[b] = silk_ADD_POS_SAT32(Xnrg[b], sumSquared);

}

else {

/* Look-ahead subframe */

Xnrg[b] = silk_ADD_POS_SAT32(Xnrg[b], silk_RSHIFT(sumSquared, 1));

}

dec_subframe_offset += dec_subframe_length;

}

psSilk_VAD->XnrgSubfr[b] = sumSquared;

}

/********************/

/* Noise estimation */

/********************/

silk_VAD_GetNoiseLevels(&Xnrg[0], psSilk_VAD);

/***********************************************/

/* Signal-plus-noise to noise ratio estimation */

/***********************************************/

sumSquared = 0;

input_tilt = 0;

for (b = 0; b < 4; b++) {

speech_nrg = Xnrg[b] - psSilk_VAD->NL[b];

if (speech_nrg > 0) {

/* Divide, with sufficient resolution */

if ((Xnrg[b] & 0xFF800000) == 0) {

NrgToNoiseRatio_Q8[b] = silk_DIV32(silk_LSHIFT(Xnrg[b], 8), psSilk_VAD->NL[b] + 1);

}

else {

NrgToNoiseRatio_Q8[b] = silk_DIV32(Xnrg[b], silk_RSHIFT(psSilk_VAD->NL[b], 8) + 1);

}

/* Convert to log domain */

SNR_Q7 = silk_lin2log(NrgToNoiseRatio_Q8[b]) - 8 * 128;

/* Sum-of-squares */

sumSquared = silk_SMLABB(sumSquared, SNR_Q7, SNR_Q7); /* Q14 */

/* Tilt measure */

if (speech_nrg < ((int)1 << 20)) {

/* Scale down SNR value for small subband speech energies */

SNR_Q7 = silk_SMULWB(silk_LSHIFT(silk_SQRT_APPROX(speech_nrg), 6), SNR_Q7);

}

input_tilt = silk_SMLAWB(input_tilt, tiltWeights[b], SNR_Q7);

}

else {

NrgToNoiseRatio_Q8[b] = 256;

}

}

/* Mean-of-squares */

sumSquared = silk_DIV32_16(sumSquared, 4); /* Q14 */

/* Root-mean-square approximation, scale to dBs, and write to output pointer */

pSNR_dB_Q7 = (short)(3 * silk_SQRT_APPROX(sumSquared)); /* Q7 */

/*********************************/

/* Speech Probability Estimation */

/*********************************/

SA_Q15 = silk_sigm_Q15(silk_SMULWB(VAD_SNR_FACTOR_Q16, pSNR_dB_Q7) - VAD_NEGATIVE_OFFSET_Q5);

/**************************/

/* Frequency Tilt Measure */

/**************************/

int input_tilt_Q15 = silk_LSHIFT(silk_sigm_Q15(input_tilt) - 16384, 1);

/**************************************************/

/* Scale the sigmoid output based on power levels */

/**************************************************/

speech_nrg = 0;

for (b = 0; b < 4; b++) {

/* Accumulate signal-without-noise energies, higher frequency bands have more weight */

speech_nrg += (b + 1) * silk_RSHIFT(Xnrg[b] - psSilk_VAD->NL[b], 4);

}

/* Power scaling */

if (speech_nrg <= 0) {

SA_Q15 = silk_RSHIFT(SA_Q15, 1);

}

else if (speech_nrg < 32768) {

if (frame_length == 10 * fs_kHz) {

speech_nrg = silk_LSHIFT_SAT32(speech_nrg, 16);

}

else {

speech_nrg = silk_LSHIFT_SAT32(speech_nrg, 15);

}

/* square-root */

speech_nrg = silk_SQRT_APPROX(speech_nrg);

SA_Q15 = silk_SMULWB(32768 + speech_nrg, SA_Q15);

}

/* Copy the resulting speech activity in Q8 */

int speech_activity_Q8 = silk_min_int(silk_RSHIFT(SA_Q15, 7), silk_uint8_MAX);

/***********************************/

/* Energy Level and SNR estimation */

/***********************************/

/* Smoothing coefficient */

smooth_coef_Q16 = silk_SMULWB(VAD_SNR_SMOOTH_COEF_Q18, silk_SMULWB((int)SA_Q15, SA_Q15));

if (frame_length == 10 * fs_kHz) {

smooth_coef_Q16 >>= 1;

}

for (b = 0; b < 4; b++) {

/* compute smoothed energy-to-noise ratio per band */

psSilk_VAD->NrgRatioSmth_Q8[b] = silk_SMLAWB(psSilk_VAD->NrgRatioSmth_Q8[b],

NrgToNoiseRatio_Q8[b] - psSilk_VAD->NrgRatioSmth_Q8[b], smooth_coef_Q16);

/* signal to noise ratio in dB per band */

SNR_Q7 = 3 * (silk_lin2log(psSilk_VAD->NrgRatioSmth_Q8[b]) - 8 * 128);

/* quality = sigmoid( 0.25 * ( SNR_dB - 16 ) ); */

input_quality_bands_Q15[b] = silk_sigm_Q15(silk_RSHIFT(SNR_Q7 - 16 * 128, 4));

}

//gap************************************************************//

if (speech_activity_Q8 < SILK_FIX_CONST(SPEECH_ACTIVITY_DTX_THRES, 8)) {

signalType = TYPE_NO_VOICE_ACTIVITY;

//noSpeechCounter++;

VAD_flag = 0;

}

else {

signalType = TYPE_UNVOICED;

VAD_flag = 1;

}

free(psSilk_VAD);

return(VAD_flag);

}