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. */ 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
