1 files changed, 30 insertions, 0 deletions
diff --git a/third_party/webrtc/src/webrtc/common_audio/signal_processing/cross_correlation.c b/third_party/webrtc/src/webrtc/common_audio/signal_processing/cross_correlation.c
new file mode 100644
index 00000000..d7c9f2b9
--- /dev/null
+++ b/third_party/webrtc/src/webrtc/common_audio/signal_processing/cross_correlation.c
@@ -0,0 +1,30 @@
+/*
+ *  Copyright (c) 2012 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.
+ */
+
+#include "webrtc/common_audio/signal_processing/include/signal_processing_library.h"
+
+/* C version of WebRtcSpl_CrossCorrelation() for generic platforms. */
+void WebRtcSpl_CrossCorrelationC(int32_t* cross_correlation,
+                                 const int16_t* seq1,
+                                 const int16_t* seq2,
+                                 size_t dim_seq,
+                                 size_t dim_cross_correlation,
+                                 int right_shifts,
+                                 int step_seq2) {
+  size_t i = 0, j = 0;
+
+  for (i = 0; i < dim_cross_correlation; i++) {
+    int32_t corr = 0;
+    for (j = 0; j < dim_seq; j++)
+      corr += (seq1[j] * seq2[j]) >> right_shifts;
+    seq2 += step_seq2;
+    *cross_correlation++ = corr;
+  }
+}