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			666 lines
		
	
	
		
			19 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			666 lines
		
	
	
		
			19 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| 
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| /******************************************************************
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| 
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|     iLBC Speech Coder ANSI-C Source Code
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| 
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|     enhancer.c 
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| 
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|     Copyright (C) The Internet Society (2004). 
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|     All Rights Reserved.
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| 
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| ******************************************************************/
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| 
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| #include <math.h>
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| #include <string.h>
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| #include "iLBC_define.h"
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| #include "enhancer.h"
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| #include "constants.h"
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| #include "filter.h"
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| 
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| /*----------------------------------------------------------------*
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| 
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| 
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|  * Find index in array such that the array element with said
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|  * index is the element of said array closest to "value" 
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|  * according to the squared-error criterion
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|  *---------------------------------------------------------------*/
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| 
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| static void NearestNeighbor(
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|     int   *index,   /* (o) index of array element closest 
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|                            to value */
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|     float *array,   /* (i) data array */
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|     float value,/* (i) value */
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|     int arlength/* (i) dimension of data array */
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| ){
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|     int i;
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|     float bestcrit,crit;
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| 
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|     crit=array[0]-value;
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|     bestcrit=crit*crit;
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|     *index=0;
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|     for (i=1; i<arlength; i++) {
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|         crit=array[i]-value;
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|         crit=crit*crit;
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|         
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|         if (crit<bestcrit) {
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|             bestcrit=crit;
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|             *index=i;
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|         }
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|     }
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| }
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| 
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| /*----------------------------------------------------------------*
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|  * compute cross correlation between sequences
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|  *---------------------------------------------------------------*/
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| 
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| static void mycorr1( 
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|     float* corr,    /* (o) correlation of seq1 and seq2 */
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|     float* seq1,    /* (i) first sequence */
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|     int dim1,           /* (i) dimension first seq1 */
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|     const float *seq2,  /* (i) second sequence */
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|     int dim2        /* (i) dimension seq2 */
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| ){
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|     int i,j;
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| 
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|     for (i=0; i<=dim1-dim2; i++) {
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|         corr[i]=0.0;
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|         for (j=0; j<dim2; j++) {
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|             corr[i] += seq1[i+j] * seq2[j];
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|         }
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|     }
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| }
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| 
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| /*----------------------------------------------------------------*
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|  * upsample finite array assuming zeros outside bounds
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|  *---------------------------------------------------------------*/
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| 
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| 
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| 
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| static void enh_upsample( 
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|     float* useq1,   /* (o) upsampled output sequence */
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|     float* seq1,/* (i) unupsampled sequence */
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|     int dim1,       /* (i) dimension seq1 */
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|     int hfl         /* (i) polyphase filter length=2*hfl+1 */
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| ){
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|     float *pu,*ps;
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|     int i,j,k,q,filterlength,hfl2;
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|     const float *polyp[ENH_UPS0]; /* pointers to 
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|                                      polyphase columns */
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|     const float *pp;
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| 
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|     /* define pointers for filter */
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| 
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|     filterlength=2*hfl+1;
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|     
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|     if ( filterlength > dim1 ) {
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|         hfl2=(int) (dim1/2);
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|         for (j=0; j<ENH_UPS0; j++) {
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|             polyp[j]=polyphaserTbl+j*filterlength+hfl-hfl2;
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|         }
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|         hfl=hfl2;
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|         filterlength=2*hfl+1;
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|     }
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|     else {
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|         for (j=0; j<ENH_UPS0; j++) {
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|             polyp[j]=polyphaserTbl+j*filterlength;
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|         }
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|     }
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| 
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|     /* filtering: filter overhangs left side of sequence */
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| 
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|     pu=useq1;
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|     for (i=hfl; i<filterlength; i++) { 
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|         for (j=0; j<ENH_UPS0; j++) {
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|             *pu=0.0;
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|             pp = polyp[j];
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|             ps = seq1+i;
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|             for (k=0; k<=i; k++) {
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|                 *pu += *ps-- * *pp++;
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|             }
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|             pu++;
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|         }
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|     }
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| 
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|     /* filtering: simple convolution=inner products */
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| 
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|     for (i=filterlength; i<dim1; i++) {
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|         for (j=0;j<ENH_UPS0; j++){
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|             *pu=0.0;
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|             pp = polyp[j];
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|             ps = seq1+i;
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|             for (k=0; k<filterlength; k++) {
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|                 *pu += *ps-- * *pp++;
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| 
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| 
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|             }
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|             pu++;
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|         }
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|     }
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| 
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|     /* filtering: filter overhangs right side of sequence */
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| 
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|     for (q=1; q<=hfl; q++) { 
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|         for (j=0; j<ENH_UPS0; j++) {
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|             *pu=0.0;
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|             pp = polyp[j]+q;
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|             ps = seq1+dim1-1;
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|             for (k=0; k<filterlength-q; k++) {
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|                 *pu += *ps-- * *pp++;
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|             }
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|             pu++;
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|         }
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|     }
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| }
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| 
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| 
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| /*----------------------------------------------------------------*
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|  * find segment starting near idata+estSegPos that has highest 
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|  * correlation with idata+centerStartPos through 
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|  * idata+centerStartPos+ENH_BLOCKL-1 segment is found at a 
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|  * resolution of ENH_UPSO times the original of the original 
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|  * sampling rate
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|  *---------------------------------------------------------------*/
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| 
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| static void refiner(
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|     float *seg,         /* (o) segment array */
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|     float *updStartPos, /* (o) updated start point */
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|     float* idata,       /* (i) original data buffer */
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|     int idatal,         /* (i) dimension of idata */
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|     int centerStartPos, /* (i) beginning center segment */
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|     float estSegPos,/* (i) estimated beginning other segment */
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|     float period    /* (i) estimated pitch period */
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| ){
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|     int estSegPosRounded,searchSegStartPos,searchSegEndPos,corrdim;
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|     int tloc,tloc2,i,st,en,fraction;
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|     float vect[ENH_VECTL],corrVec[ENH_CORRDIM],maxv;
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|     float corrVecUps[ENH_CORRDIM*ENH_UPS0];
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| 
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|     /* defining array bounds */
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|     
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|     estSegPosRounded=(int)(estSegPos - 0.5);
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| 
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|     searchSegStartPos=estSegPosRounded-ENH_SLOP;
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|     
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|     if (searchSegStartPos<0) { 
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|         searchSegStartPos=0;
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|     }
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|     searchSegEndPos=estSegPosRounded+ENH_SLOP;
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|     
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| 
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| 
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|     if (searchSegEndPos+ENH_BLOCKL >= idatal) { 
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|         searchSegEndPos=idatal-ENH_BLOCKL-1;
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|     }
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|     corrdim=searchSegEndPos-searchSegStartPos+1;
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|     
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|     /* compute upsampled correlation (corr33) and find 
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|        location of max */
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| 
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|     mycorr1(corrVec,idata+searchSegStartPos,
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|         corrdim+ENH_BLOCKL-1,idata+centerStartPos,ENH_BLOCKL);
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|     enh_upsample(corrVecUps,corrVec,corrdim,ENH_FL0);
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|     tloc=0; maxv=corrVecUps[0];
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|     for (i=1; i<ENH_UPS0*corrdim; i++) {
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|         
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|         if (corrVecUps[i]>maxv) {
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|             tloc=i;
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|             maxv=corrVecUps[i];
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|         }
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|     }
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|     
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|     /* make vector can be upsampled without ever running outside 
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|        bounds */
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|     
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|     *updStartPos= (float)searchSegStartPos + 
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|         (float)tloc/(float)ENH_UPS0+(float)1.0;
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|     tloc2=(int)(tloc/ENH_UPS0);
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|     
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|     if (tloc>tloc2*ENH_UPS0) {
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|         tloc2++;
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|     }
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|     st=searchSegStartPos+tloc2-ENH_FL0;
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|     
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|     if (st<0) {
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|         memset(vect,0,-st*sizeof(float));
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|         memcpy(&vect[-st],idata, (ENH_VECTL+st)*sizeof(float));
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|     }
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|     else {
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|         en=st+ENH_VECTL;
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|         
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|         if (en>idatal) {
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|             memcpy(vect, &idata[st], 
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|                 (ENH_VECTL-(en-idatal))*sizeof(float));
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|             memset(&vect[ENH_VECTL-(en-idatal)], 0, 
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|                 (en-idatal)*sizeof(float));
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|         }
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|         else {
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|             memcpy(vect, &idata[st], ENH_VECTL*sizeof(float));
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|         }
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|     }
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|     fraction=tloc2*ENH_UPS0-tloc;
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|     
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|     /* compute the segment (this is actually a convolution) */
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| 
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|     mycorr1(seg,vect,ENH_VECTL,polyphaserTbl+(2*ENH_FL0+1)*fraction,
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| 
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| 
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|         2*ENH_FL0+1);
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| }
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| 
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| /*----------------------------------------------------------------*
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|  * find the smoothed output data
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|  *---------------------------------------------------------------*/
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| 
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| static void smath(
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|     float *odata,   /* (o) smoothed output */
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|     float *sseq,/* (i) said second sequence of waveforms */
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|     int hl,         /* (i) 2*hl+1 is sseq dimension */
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|     float alpha0/* (i) max smoothing energy fraction */
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| ){
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|     int i,k;
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|     float w00,w10,w11,A,B,C,*psseq,err,errs;
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|     float surround[BLOCKL_MAX]; /* shape contributed by other than 
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|                                    current */
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|     float wt[2*ENH_HL+1];       /* waveform weighting to get 
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|                                    surround shape */
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|     float denom;
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|     
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|     /* create shape of contribution from all waveforms except the
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|        current one */
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| 
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|     for (i=1; i<=2*hl+1; i++) {
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|         wt[i-1] = (float)0.5*(1 - (float)cos(2*PI*i/(2*hl+2))); 
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|     }
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|     wt[hl]=0.0; /* for clarity, not used */
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|     for (i=0; i<ENH_BLOCKL; i++) {
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|         surround[i]=sseq[i]*wt[0];
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|     }
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|     for (k=1; k<hl; k++) {
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|         psseq=sseq+k*ENH_BLOCKL;
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|         for(i=0;i<ENH_BLOCKL; i++) {
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|             surround[i]+=psseq[i]*wt[k];
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|         }
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|     }
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|     for (k=hl+1; k<=2*hl; k++) {
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|         psseq=sseq+k*ENH_BLOCKL;
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|         for(i=0;i<ENH_BLOCKL; i++) {
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|             surround[i]+=psseq[i]*wt[k];
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|         }
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|     }
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|     
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|     /* compute some inner products */
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| 
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|     w00 = w10 = w11 = 0.0;
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|     psseq=sseq+hl*ENH_BLOCKL; /* current block  */
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|     for (i=0; i<ENH_BLOCKL;i++) {
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|         w00+=psseq[i]*psseq[i];
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|         w11+=surround[i]*surround[i];
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|         w10+=surround[i]*psseq[i];
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|     }
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|     
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| 
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| 
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|     if (fabs(w11) < 1.0) {
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|         w11=1.0;
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|     }
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|     C = (float)sqrt( w00/w11);
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|     
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|     /* first try enhancement without power-constraint */
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| 
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|     errs=0.0;
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|     psseq=sseq+hl*ENH_BLOCKL;
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|     for (i=0; i<ENH_BLOCKL; i++) {
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|         odata[i]=C*surround[i];
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|         err=psseq[i]-odata[i];
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|         errs+=err*err;
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|     }
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|     
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|     /* if constraint violated by first try, add constraint */ 
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|     
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|     if (errs > alpha0 * w00) {
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|         if ( w00 < 1) {
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|             w00=1;
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|         }
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|         denom = (w11*w00-w10*w10)/(w00*w00);
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|         
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|         if (denom > 0.0001) { /* eliminates numerical problems 
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|                                  for if smooth */
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|             A = (float)sqrt( (alpha0- alpha0*alpha0/4)/denom);
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|             B = -alpha0/2 - A * w10/w00;
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|             B = B+1;
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|         }
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|         else { /* essentially no difference between cycles; 
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|                   smoothing not needed */
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|             A= 0.0;
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|             B= 1.0;
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|         }
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|         
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|         /* create smoothed sequence */
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| 
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|         psseq=sseq+hl*ENH_BLOCKL;
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|         for (i=0; i<ENH_BLOCKL; i++) {
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|             odata[i]=A*surround[i]+B*psseq[i];
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|         }
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|     }
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| }
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| 
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| /*----------------------------------------------------------------*
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|  * get the pitch-synchronous sample sequence
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|  *---------------------------------------------------------------*/
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| 
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| static void getsseq(
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|     float *sseq,    /* (o) the pitch-synchronous sequence */
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|     float *idata,       /* (i) original data */
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|     int idatal,         /* (i) dimension of data */
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|     int centerStartPos, /* (i) where current block starts */
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|     float *period,      /* (i) rough-pitch-period array */
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| 
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| 
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|     float *plocs,       /* (i) where periods of period array 
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|                                are taken */
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|     int periodl,    /* (i) dimension period array */
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|     int hl              /* (i) 2*hl+1 is the number of sequences */
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| ){
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|     int i,centerEndPos,q;
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|     float blockStartPos[2*ENH_HL+1];
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|     int lagBlock[2*ENH_HL+1];
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|     float plocs2[ENH_PLOCSL]; 
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|     float *psseq;
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| 
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|     centerEndPos=centerStartPos+ENH_BLOCKL-1;
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|     
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|     /* present */
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| 
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|     NearestNeighbor(lagBlock+hl,plocs,
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|         (float)0.5*(centerStartPos+centerEndPos),periodl);
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|     
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|     blockStartPos[hl]=(float)centerStartPos;
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|     psseq=sseq+ENH_BLOCKL*hl;
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|     memcpy(psseq, idata+centerStartPos, ENH_BLOCKL*sizeof(float));
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|     
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|     /* past */
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| 
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|     for (q=hl-1; q>=0; q--) {
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|         blockStartPos[q]=blockStartPos[q+1]-period[lagBlock[q+1]];
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|         NearestNeighbor(lagBlock+q,plocs,
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|             blockStartPos[q]+
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|             ENH_BLOCKL_HALF-period[lagBlock[q+1]], periodl);
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|                             
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|         
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|         if (blockStartPos[q]-ENH_OVERHANG>=0) {
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|             refiner(sseq+q*ENH_BLOCKL, blockStartPos+q, idata,
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|                 idatal, centerStartPos, blockStartPos[q],
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|                 period[lagBlock[q+1]]);
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|         } else {
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|             psseq=sseq+q*ENH_BLOCKL;
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|             memset(psseq, 0, ENH_BLOCKL*sizeof(float));
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|         }
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|     }
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|     
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|     /* future */
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| 
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|     for (i=0; i<periodl; i++) {
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|         plocs2[i]=plocs[i]-period[i];
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|     }
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|     for (q=hl+1; q<=2*hl; q++) { 
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|         NearestNeighbor(lagBlock+q,plocs2,
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|             blockStartPos[q-1]+ENH_BLOCKL_HALF,periodl);
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| 
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|         blockStartPos[q]=blockStartPos[q-1]+period[lagBlock[q]];
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|         if (blockStartPos[q]+ENH_BLOCKL+ENH_OVERHANG<idatal) {
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|             refiner(sseq+ENH_BLOCKL*q, blockStartPos+q, idata,
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|                 idatal, centerStartPos, blockStartPos[q],
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| 
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| 
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|                 period[lagBlock[q]]);
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|         }
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|         else {
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|             psseq=sseq+q*ENH_BLOCKL;
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|             memset(psseq, 0, ENH_BLOCKL*sizeof(float));
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|         }
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|     }
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| }
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| 
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| /*----------------------------------------------------------------*
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|  * perform enhancement on idata+centerStartPos through 
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|  * idata+centerStartPos+ENH_BLOCKL-1
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|  *---------------------------------------------------------------*/
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| 
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| static void enhancer(
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|     float *odata,       /* (o) smoothed block, dimension blockl */
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|     float *idata,       /* (i) data buffer used for enhancing */
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|     int idatal,         /* (i) dimension idata */
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|     int centerStartPos, /* (i) first sample current block 
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|                                within idata */
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|     float alpha0,       /* (i) max correction-energy-fraction 
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|                               (in [0,1]) */
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|     float *period,      /* (i) pitch period array */
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|     float *plocs,       /* (i) locations where period array 
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|                                values valid */
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|     int periodl         /* (i) dimension of period and plocs */
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| ){
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|     float sseq[(2*ENH_HL+1)*ENH_BLOCKL];
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| 
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|     /* get said second sequence of segments */
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| 
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|     getsseq(sseq,idata,idatal,centerStartPos,period,
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|         plocs,periodl,ENH_HL);
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| 
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|     /* compute the smoothed output from said second sequence */
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| 
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|     smath(odata,sseq,ENH_HL,alpha0);
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| 
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| }
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| 
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| /*----------------------------------------------------------------*
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|  * cross correlation
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|  *---------------------------------------------------------------*/
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| 
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| float xCorrCoef( 
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|     float *target,      /* (i) first array */
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|     float *regressor,   /* (i) second array */
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|     int subl        /* (i) dimension arrays */
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| ){
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|     int i;
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|     float ftmp1, ftmp2;
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|         
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|     ftmp1 = 0.0;
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|     ftmp2 = 0.0;
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| 
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| 
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|     for (i=0; i<subl; i++) {
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|         ftmp1 += target[i]*regressor[i];
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|         ftmp2 += regressor[i]*regressor[i]; 
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|     }
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|     
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|     if (ftmp1 > 0.0) {
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|         return (float)(ftmp1*ftmp1/ftmp2);
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|     }
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|     else {
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|         return (float)0.0;
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|     }
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| }
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| 
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| /*----------------------------------------------------------------*
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|  * interface for enhancer
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|  *---------------------------------------------------------------*/
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| 
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| int enhancerInterface(
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|     float *out,                     /* (o) enhanced signal */
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|     float *in,                      /* (i) unenhanced signal */
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|     iLBC_Dec_Inst_t *iLBCdec_inst   /* (i) buffers etc */
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| ){
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|     float *enh_buf, *enh_period;
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|     int iblock, isample;
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|     int lag=0, ilag, i, ioffset;
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|     float cc, maxcc;
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|     float ftmp1, ftmp2;
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|     float *inPtr, *enh_bufPtr1, *enh_bufPtr2;
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|     float plc_pred[ENH_BLOCKL];
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| 
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|     float lpState[6], downsampled[(ENH_NBLOCKS*ENH_BLOCKL+120)/2];
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|     int inLen=ENH_NBLOCKS*ENH_BLOCKL+120;
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|     int start, plc_blockl, inlag;
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| 
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|     enh_buf=iLBCdec_inst->enh_buf;
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|     enh_period=iLBCdec_inst->enh_period;
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|     
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|     memmove(enh_buf, &enh_buf[iLBCdec_inst->blockl], 
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|         (ENH_BUFL-iLBCdec_inst->blockl)*sizeof(float));
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|                                                             
 | |
|     memcpy(&enh_buf[ENH_BUFL-iLBCdec_inst->blockl], in, 
 | |
|         iLBCdec_inst->blockl*sizeof(float));
 | |
| 
 | |
|     if (iLBCdec_inst->mode==30)
 | |
|         plc_blockl=ENH_BLOCKL;
 | |
|     else
 | |
|         plc_blockl=40;
 | |
| 
 | |
|     /* when 20 ms frame, move processing one block */
 | |
|     ioffset=0;
 | |
|     if (iLBCdec_inst->mode==20) ioffset=1;
 | |
| 
 | |
|     i=3-ioffset;
 | |
|     memmove(enh_period, &enh_period[i], 
 | |
| 
 | |
| 
 | |
|         (ENH_NBLOCKS_TOT-i)*sizeof(float));
 | |
| 
 | |
|     /* Set state information to the 6 samples right before 
 | |
|        the samples to be downsampled. */
 | |
| 
 | |
|     memcpy(lpState, 
 | |
|         enh_buf+(ENH_NBLOCKS_EXTRA+ioffset)*ENH_BLOCKL-126, 
 | |
|         6*sizeof(float));
 | |
| 
 | |
|     /* Down sample a factor 2 to save computations */
 | |
| 
 | |
|     DownSample(enh_buf+(ENH_NBLOCKS_EXTRA+ioffset)*ENH_BLOCKL-120,
 | |
|                 lpFilt_coefsTbl, inLen-ioffset*ENH_BLOCKL,
 | |
|                 lpState, downsampled);
 | |
| 
 | |
|     /* Estimate the pitch in the down sampled domain. */
 | |
|     for (iblock = 0; iblock<ENH_NBLOCKS-ioffset; iblock++) {
 | |
|         
 | |
|         lag = 10;
 | |
|         maxcc = xCorrCoef(downsampled+60+iblock*
 | |
|             ENH_BLOCKL_HALF, downsampled+60+iblock*
 | |
|             ENH_BLOCKL_HALF-lag, ENH_BLOCKL_HALF);
 | |
|         for (ilag=11; ilag<60; ilag++) {
 | |
|             cc = xCorrCoef(downsampled+60+iblock*
 | |
|                 ENH_BLOCKL_HALF, downsampled+60+iblock*
 | |
|                 ENH_BLOCKL_HALF-ilag, ENH_BLOCKL_HALF);
 | |
|             
 | |
|             if (cc > maxcc) {
 | |
|                 maxcc = cc;
 | |
|                 lag = ilag;
 | |
|             }
 | |
|         }
 | |
| 
 | |
|         /* Store the estimated lag in the non-downsampled domain */
 | |
|         enh_period[iblock+ENH_NBLOCKS_EXTRA+ioffset] = (float)lag*2;
 | |
| 
 | |
| 
 | |
|     }   
 | |
| 
 | |
| 
 | |
|     /* PLC was performed on the previous packet */
 | |
|     if (iLBCdec_inst->prev_enh_pl==1) {
 | |
| 
 | |
|         inlag=(int)enh_period[ENH_NBLOCKS_EXTRA+ioffset];
 | |
| 
 | |
|         lag = inlag-1;
 | |
|         maxcc = xCorrCoef(in, in+lag, plc_blockl);
 | |
|         for (ilag=inlag; ilag<=inlag+1; ilag++) {
 | |
|             cc = xCorrCoef(in, in+ilag, plc_blockl);
 | |
|             
 | |
|             if (cc > maxcc) {
 | |
|                 maxcc = cc;
 | |
|                 lag = ilag;
 | |
|             }
 | |
|         }
 | |
| 
 | |
| 
 | |
| 
 | |
|         enh_period[ENH_NBLOCKS_EXTRA+ioffset-1]=(float)lag;
 | |
| 
 | |
|         /* compute new concealed residual for the old lookahead,
 | |
|            mix the forward PLC with a backward PLC from 
 | |
|            the new frame */
 | |
|         
 | |
|         inPtr=&in[lag-1];
 | |
|         
 | |
|         enh_bufPtr1=&plc_pred[plc_blockl-1];
 | |
|         
 | |
|         if (lag>plc_blockl) {
 | |
|             start=plc_blockl;
 | |
|         } else {
 | |
|             start=lag;
 | |
|         }
 | |
| 
 | |
|         for (isample = start; isample>0; isample--) {
 | |
|             *enh_bufPtr1-- = *inPtr--;
 | |
|         }
 | |
|         
 | |
|         enh_bufPtr2=&enh_buf[ENH_BUFL-1-iLBCdec_inst->blockl];
 | |
|         for (isample = (plc_blockl-1-lag); isample>=0; isample--) 
 | |
| {
 | |
|             *enh_bufPtr1-- = *enh_bufPtr2--;
 | |
|         }
 | |
| 
 | |
|         /* limit energy change */
 | |
|         ftmp2=0.0;
 | |
|         ftmp1=0.0;
 | |
|         for (i=0;i<plc_blockl;i++) {
 | |
|             ftmp2+=enh_buf[ENH_BUFL-1-iLBCdec_inst->blockl-i]*
 | |
|                 enh_buf[ENH_BUFL-1-iLBCdec_inst->blockl-i];
 | |
|             ftmp1+=plc_pred[i]*plc_pred[i];
 | |
|         }
 | |
|         ftmp1=(float)sqrt(ftmp1/(float)plc_blockl);
 | |
|         ftmp2=(float)sqrt(ftmp2/(float)plc_blockl);
 | |
|         if (ftmp1>(float)2.0*ftmp2 && ftmp1>0.0) {
 | |
|             for (i=0;i<plc_blockl-10;i++) {
 | |
|                 plc_pred[i]*=(float)2.0*ftmp2/ftmp1;
 | |
|             }
 | |
|             for (i=plc_blockl-10;i<plc_blockl;i++) {
 | |
|                 plc_pred[i]*=(float)(i-plc_blockl+10)*
 | |
|                     ((float)1.0-(float)2.0*ftmp2/ftmp1)/(float)(10)+
 | |
|                     (float)2.0*ftmp2/ftmp1;
 | |
|             }
 | |
|         }
 | |
|     
 | |
|         enh_bufPtr1=&enh_buf[ENH_BUFL-1-iLBCdec_inst->blockl];
 | |
|         for (i=0; i<plc_blockl; i++) {
 | |
|             ftmp1 = (float) (i+1) / (float) (plc_blockl+1);
 | |
|             *enh_bufPtr1 *= ftmp1;
 | |
|             *enh_bufPtr1 += ((float)1.0-ftmp1)*
 | |
|                                 plc_pred[plc_blockl-1-i];
 | |
|             enh_bufPtr1--;
 | |
|         }
 | |
| 
 | |
| 
 | |
|     }
 | |
| 
 | |
|     if (iLBCdec_inst->mode==20) {
 | |
|         /* Enhancer with 40 samples delay */
 | |
|         for (iblock = 0; iblock<2; iblock++) {
 | |
|             enhancer(out+iblock*ENH_BLOCKL, enh_buf, 
 | |
|                 ENH_BUFL, (5+iblock)*ENH_BLOCKL+40,
 | |
|                 ENH_ALPHA0, enh_period, enh_plocsTbl, 
 | |
|                     ENH_NBLOCKS_TOT);
 | |
|         }
 | |
|     } else if (iLBCdec_inst->mode==30) {
 | |
|         /* Enhancer with 80 samples delay */
 | |
|         for (iblock = 0; iblock<3; iblock++) {
 | |
|             enhancer(out+iblock*ENH_BLOCKL, enh_buf, 
 | |
|                 ENH_BUFL, (4+iblock)*ENH_BLOCKL,
 | |
|                 ENH_ALPHA0, enh_period, enh_plocsTbl, 
 | |
|                     ENH_NBLOCKS_TOT);
 | |
|         }
 | |
|     }
 | |
| 
 | |
|     return (lag*2);
 | |
| }
 | |
| 
 | |
| 
 |