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diff --git a/webrtc/modules/video_coding/rtt_filter.h b/webrtc/modules/video_coding/rtt_filter.h
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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.
+ */
+
+#ifndef WEBRTC_MODULES_VIDEO_CODING_RTT_FILTER_H_
+#define WEBRTC_MODULES_VIDEO_CODING_RTT_FILTER_H_
+
+#include "webrtc/typedefs.h"
+
+namespace webrtc {
+
+class VCMRttFilter {
+ public:
+  VCMRttFilter();
+
+  VCMRttFilter& operator=(const VCMRttFilter& rhs);
+
+  // Resets the filter.
+  void Reset();
+  // Updates the filter with a new sample.
+  void Update(int64_t rttMs);
+  // A getter function for the current RTT level in ms.
+  int64_t RttMs() const;
+
+ private:
+  // The size of the drift and jump memory buffers
+  // and thus also the detection threshold for these
+  // detectors in number of samples.
+  enum { kMaxDriftJumpCount = 5 };
+  // Detects RTT jumps by comparing the difference between
+  // samples and average to the standard deviation.
+  // Returns true if the long time statistics should be updated
+  // and false otherwise
+  bool JumpDetection(int64_t rttMs);
+  // Detects RTT drifts by comparing the difference between
+  // max and average to the standard deviation.
+  // Returns true if the long time statistics should be updated
+  // and false otherwise
+  bool DriftDetection(int64_t rttMs);
+  // Computes the short time average and maximum of the vector buf.
+  void ShortRttFilter(int64_t* buf, uint32_t length);
+
+  bool _gotNonZeroUpdate;
+  double _avgRtt;
+  double _varRtt;
+  int64_t _maxRtt;
+  uint32_t _filtFactCount;
+  const uint32_t _filtFactMax;
+  const double _jumpStdDevs;
+  const double _driftStdDevs;
+  int32_t _jumpCount;
+  int32_t _driftCount;
+  const int32_t _detectThreshold;
+  int64_t _jumpBuf[kMaxDriftJumpCount];
+  int64_t _driftBuf[kMaxDriftJumpCount];
+};
+
+}  // namespace webrtc
+
+#endif  // WEBRTC_MODULES_VIDEO_CODING_RTT_FILTER_H_