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/*
* Copyright (c) 2011 The WebRTC project authors. All Rights Reserved.
*
* Use of this source code is governed by a BSD-style license
* that can be found in the LICENSE file in the root of the source
* tree. An additional intellectual property rights grant can be found
* in the file PATENTS. All contributing project authors may
* be found in the AUTHORS file in the root of the source tree.
*/
/******************************************************************
iLBC Speech Coder ANSI-C Source Code
WebRtcIlbcfix_MyCorr.c
******************************************************************/
#include "defines.h"
/*----------------------------------------------------------------*
* compute cross correlation between sequences
*---------------------------------------------------------------*/
void WebRtcIlbcfix_MyCorr(
int32_t *corr, /* (o) correlation of seq1 and seq2 */
int16_t *seq1, /* (i) first sequence */
int16_t dim1, /* (i) dimension first seq1 */
const int16_t *seq2, /* (i) second sequence */
int16_t dim2 /* (i) dimension seq2 */
){
int16_t max, scale, loops;
/* Calculate correlation between the two sequences. Scale the
result of the multiplcication to maximum 26 bits in order
to avoid overflow */
max=WebRtcSpl_MaxAbsValueW16(seq1, dim1);
scale=WebRtcSpl_GetSizeInBits(max);
scale = (int16_t)(WEBRTC_SPL_MUL_16_16(2,scale)-26);
if (scale<0) {
scale=0;
}
loops=dim1-dim2+1;
/* Calculate the cross correlations */
WebRtcSpl_CrossCorrelation(corr, (int16_t*)seq2, seq1, dim2, loops, scale, 1);
return;
}
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