www.pudn.com > ETSI_ES_202_212_software.rar > VAD.c
/*===============================================================================
* ETSI ES 202 212 Distributed Speech Recognition
* Extended Advanced Front-End Feature Extraction Algorithm & Compression Algorithm
* Speech Reconstruction Algorithm.
* C-language software implementation
* Version 1.1.1 October, 2003
*===============================================================================*/
/*-------------------------------------------------------------------------------
*
* FILE NAME: VAD.c
* PURPOSE: Logic for the frame dropping VAD. VAD flag is set
* according to parameters (SpeechFoundSpec, SpeechFoundMel,
* SpeechFoundVar) calculated in NoiseSup.c.
*
*-------------------------------------------------------------------------------*/
/*-----------------
* File Inclusions
*-----------------*/
#include
#include
#include "ParmInterface.h"
#include "VADExports.h"
/*----------------
* VAD Definitions
*-----------------*/
struct VADStructX
{
int Focus; //Position of circular buffer
int HangOver; //Hangover length
int FlushFocus; //Position in circular buffer when emptying at end (uses Focus as start/endpoint)
int H_CountDown; //Main hangover countdown
int V_CountDown; //Short hangover countdown
int DangerWillRobinson; //No output flag
float **OutBuffer; //
};
#define PRINTVAD 0
#define PRINTNULLS 0
#define BUFFER_SIZE 7 // Number of frames in analysis buffer
#define HANGOVERV 23 // Number of frames by which VAD will stay on after speech
#define H_TRIGGER 4 // Number of speech frames required to trigger hangover NB Must be <= BUFFER_SIZE!!
#define VANGOVER 5 // Number of frames for short hangover, triggered by 3 frames of speech
#define V_TRIGGER 3 // Number of speech frames required to trigger VAD
#define SANGOVER 50 // Number of frames for safety hangover
/*----------------------------------------------------------------------------
* FUNCTION NAME: focalpoint
*
* PURPOSE: CONTROL VAD BUFFER
*
* INPUT:
* Focus current focal point
* offset change in focal point
*
* OUTPUT:
* None
*
*
* RETURN VALUE:
* temp new focal point within Buffer boundary
*
*
*---------------------------------------------------------------------------*/
int focalpoint (int Focus, int offset)
{
int temp;
temp = Focus + offset;
if (temp > (BUFFER_SIZE-1)) temp = temp - BUFFER_SIZE;
if (temp < 0) temp = temp + BUFFER_SIZE;
return (temp);
}
/*----------------------------------------------------------------------------
* FUNCTION NAME: DoVADAlloc
*
* PURPOSE: Allocation of memory to VAD structure
*
*
* INPUT:
* None
*
*
* OUTPUT:
* None
*
*
* RETURN VALUE:
* VADX Pointer to VADStructX
*
*
*---------------------------------------------------------------------------*/
extern VADStructX *DoVADAlloc (void)
{
VADStructX *VADX = calloc (1, sizeof (VADStructX));
return VADX;
}
/*----------------------------------------------------------------------------
* FUNCTION NAME: DoVADInit
*
* PURPOSE: Initialises VAD structure
*
*
* INPUT:
* This Pointer to front end parameter structure
*
*
* OUTPUT:
* This Pointer to front end parameter structure
*
*
* RETURN VALUE:
* None
*
*
*---------------------------------------------------------------------------*/
extern void DoVADInit (FEParamsX *This)
{
int i ;
VADStructX *VADX = This->VADX;
VADX->Focus = 0;
VADX->HangOver = HANGOVERV;
VADX->H_CountDown = 0;
VADX->V_CountDown = 0;
VADX->DangerWillRobinson = 1;
VADX->FlushFocus = -1;
VADX->OutBuffer = calloc (BUFFER_SIZE, sizeof (VADX->OutBuffer[0])) ;
if (VADX->OutBuffer == NULL)
{
fprintf (stderr, "Allocation error Outbuffer\n");
exit(0);
}
for (i=0 ; iOutBuffer[i] = calloc (NUM_CEP_COEFF+2, sizeof (VADX->OutBuffer[0][0])) ;
if (VADX->OutBuffer[i] == NULL)
{
fprintf (stderr, "Allocation error Outbuffer\n");
exit(0);
}
}
}
/*----------------------------------------------------------------------------
* FUNCTION NAME: DoVADDelete
*
* PURPOSE: Free VAD structure
*
*
* INPUT:
* VADX Pointer to VAD structure
*
*
* OUTPUT:
* VADX Pointer to empty VAD structure
*
*
* RETURN VALUE:
* None
*
*
*---------------------------------------------------------------------------*/
extern void DoVADDelete (VADStructX *VADX)
{
int i;
for (i=0 ; iOutBuffer[i] != NULL) free (VADX->OutBuffer[i]) ;
}
if (VADX->OutBuffer != NULL) free (VADX->OutBuffer) ;
if (VADX != NULL)
free (VADX);
}
/*----------------------------------------------------------------------------
* FUNCTION NAME: DoVADProc
*
* PURPOSE: Identifies speech and non-speech frames
*
*
* INPUT:
* FeatureBuffer Buffer of features
* This Pointer to front end parameter structure
*
*
* OUTPUT:
* FeatureBuffer Buffer of features
* This Pointer to front end parameter structure
*
*
* RETURN VALUE:
* TRUE Once buffer is full
* FALSE For first 10 frames
*
*
*---------------------------------------------------------------------------*/
extern BOOLEAN DoVADProc (X_FLOAT32 *FeatureBuffer, FEParamsX *This)
{
VADStructX *VADX = This->VADX;
int i;
int Sum;
int Trigger;
int Refocus;
int Focus = VADX->Focus;
int HangOver = VADX->HangOver;
int H_CountDown = VADX->H_CountDown;
int V_CountDown = VADX->V_CountDown;
int DangerWillRobinson = VADX->DangerWillRobinson;
float **OutBuffer = VADX->OutBuffer;
/*------------------
*
*------------------*/
Focus++;
if (Focus == BUFFER_SIZE) Focus = 0;
for (i=0 ; iSpeechFoundSpec || This->SpeechFoundMel || This->SpeechFoundVar || This->SpeechFoundVADNS)
{
OutBuffer[Focus][NUM_CEP_COEFF+1] = 1;
}
else
{
OutBuffer[Focus][NUM_CEP_COEFF+1] = 0;
}
//+3 due to changes in lookahead
if (This->FrameCounter > (BUFFER_SIZE+3))
{
Sum=0;Trigger=0;
for (i=0 ; i Trigger)
{
Trigger = Sum;
}
Sum = 0;
}
}
if (Sum > Trigger)
{
Trigger = Sum;
}
if (Trigger>=H_TRIGGER)
{
H_CountDown = HangOver;
DangerWillRobinson = 0;
if (This->FrameCounter <= 35) HangOver = SANGOVER;
}
if (H_CountDown && Trigger < V_TRIGGER)
{
H_CountDown--;
}
if (Trigger >= V_TRIGGER)
{
V_CountDown = VANGOVER;
}
if (V_CountDown && Trigger < V_TRIGGER)
{
V_CountDown--;
}
Refocus = focalpoint (Focus, 1);
for (i=0 ; i<=NUM_CEP_COEFF+1 ; i++) FeatureBuffer[i] = OutBuffer[Refocus][i];
if (V_CountDown || H_CountDown || Trigger >= V_TRIGGER)
{
FeatureBuffer[NUM_CEP_COEFF+1] = 1.0;
}
else
{
FeatureBuffer[NUM_CEP_COEFF+1] = 0.0;
if (PRINTNULLS) fprintf (stderr, "%d,", This->FrameCounter-(BUFFER_SIZE+3));
}
This->VAD = (int)FeatureBuffer[NUM_CEP_COEFF+1];
VADX->Focus = Focus;
VADX->HangOver = HangOver;
VADX->H_CountDown = H_CountDown;
VADX->V_CountDown = V_CountDown;
VADX->DangerWillRobinson = DangerWillRobinson;
return TRUE;
}
else
{
VADX->Focus = Focus;
VADX->HangOver = HangOver;
VADX->H_CountDown = H_CountDown;
VADX->V_CountDown = V_CountDown;
VADX->DangerWillRobinson = DangerWillRobinson;
return FALSE;
}
}
/*----------------------------------------------------------------------------
* FUNCTION NAME: DoVADFlush
*
* PURPOSE: Flush remaining data from VAD Buffer
*
*
* INPUT:
* FeatureBuffer Buffer of features
* This Pointer to front end parameter structure
*
*
* OUTPUT:
* FeatureBuffer Buffer of features
* This Pointer to front end parameter structure
*
*
* RETURN VALUE:
* TRUE When VAD buffer is being flushed
* FALSE When flushing is complete
*
*
*---------------------------------------------------------------------------*/
extern BOOLEAN DoVADFlush (X_FLOAT32 *FeatureBuffer, FEParamsX *This)
{
VADStructX *VADX = This->VADX;
int i;
int Sum;
int Trigger;
int Refocus;
int Focus = VADX->Focus;
int HangOver = VADX->HangOver;
int H_CountDown = VADX->H_CountDown;
int V_CountDown = VADX->V_CountDown;
int DangerWillRobinson = VADX->DangerWillRobinson;
float **OutBuffer = VADX->OutBuffer;
// Last frame output from loop
if (VADX->FlushFocus == -1) VADX->FlushFocus = Focus;
// Move forward one step
Focus++;
if (Focus == BUFFER_SIZE) Focus = 0;
if (Focus != VADX->FlushFocus)
{
// Flush remaining data
// Need to keep the counter incrementing!
This->FrameCounter++;
// +3 due to changes in lookahead
if (This->FrameCounter > (BUFFER_SIZE+3))
{
Sum = 0;
Trigger = 0;
for (i=0 ; i Trigger)
{
Trigger = Sum;
}
Sum = 0;
}
}
if (Sum > Trigger)
{
Trigger = Sum;
}
if (Trigger >= H_TRIGGER)
{
H_CountDown=HangOver;
DangerWillRobinson = 0;
if (This->FrameCounter <= 35) HangOver = SANGOVER;
}
if (H_CountDown&&Trigger < V_TRIGGER)
{
H_CountDown--;
}
if (Trigger >= V_TRIGGER)
{
V_CountDown = VANGOVER;
}
if (V_CountDown&&Trigger < V_TRIGGER)
{
V_CountDown--;
}
Refocus = focalpoint (Focus, 1);
for (i=0 ; i<=NUM_CEP_COEFF+1 ; i++) FeatureBuffer[i] = OutBuffer[Refocus][i];
if (V_CountDown || H_CountDown || Trigger>=V_TRIGGER)
{
FeatureBuffer[NUM_CEP_COEFF+1] = 1.0;
}
else
{
FeatureBuffer[NUM_CEP_COEFF+1] = 0.0;
if (PRINTNULLS) fprintf (stderr, "%d,", This->FrameCounter-(BUFFER_SIZE+3));
}
/*------------------
* Output result
*------------------*/
This->VAD = (int)FeatureBuffer[NUM_CEP_COEFF+1];
}
VADX->Focus = Focus;
VADX->HangOver = HangOver;
VADX->H_CountDown = H_CountDown;
VADX->V_CountDown = V_CountDown;
VADX->DangerWillRobinson = DangerWillRobinson;
return TRUE;
}
else
{
return FALSE;
}
}