1 /*
2 * Copyright (c) 2012 The WebRTC project authors. All Rights Reserved.
3 *
4 * Use of this source code is governed by a BSD-style license
5 * that can be found in the LICENSE file in the root of the source
6 * tree. An additional intellectual property rights grant can be found
7 * in the file PATENTS. All contributing project authors may
8 * be found in the AUTHORS file in the root of the source tree.
9 */
10
11 #include "webrtc/common_audio/signal_processing/include/signal_processing_library.h"
12
13 /* C version of WebRtcSpl_CrossCorrelation() for generic platforms. */
WebRtcSpl_CrossCorrelationC(int32_t * cross_correlation,const int16_t * seq1,const int16_t * seq2,int16_t dim_seq,int16_t dim_cross_correlation,int16_t right_shifts,int16_t step_seq2)14 void WebRtcSpl_CrossCorrelationC(int32_t* cross_correlation,
15 const int16_t* seq1,
16 const int16_t* seq2,
17 int16_t dim_seq,
18 int16_t dim_cross_correlation,
19 int16_t right_shifts,
20 int16_t step_seq2) {
21 int i = 0, j = 0;
22
23 for (i = 0; i < dim_cross_correlation; i++) {
24 *cross_correlation = 0;
25 /* Unrolling doesn't seem to improve performance. */
26 for (j = 0; j < dim_seq; j++) {
27 *cross_correlation += (seq1[j] * seq2[step_seq2 * i + j]) >> right_shifts;
28 }
29 cross_correlation++;
30 }
31 }
32