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diff --git a/webrtc/modules/video_coding/inter_frame_delay.h b/webrtc/modules/video_coding/inter_frame_delay.h
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+++ b/webrtc/modules/video_coding/inter_frame_delay.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_INTER_FRAME_DELAY_H_
+#define WEBRTC_MODULES_VIDEO_CODING_INTER_FRAME_DELAY_H_
+
+#include "webrtc/typedefs.h"
+
+namespace webrtc {
+
+class VCMInterFrameDelay {
+ public:
+  explicit VCMInterFrameDelay(int64_t currentWallClock);
+
+  // Resets the estimate. Zeros are given as parameters.
+  void Reset(int64_t currentWallClock);
+
+  // Calculates the delay of a frame with the given timestamp.
+  // This method is called when the frame is complete.
+  //
+  // Input:
+  //          - timestamp         : RTP timestamp of a received frame
+  //          - *delay            : Pointer to memory where the result should be
+  //          stored
+  //          - currentWallClock  : The current time in milliseconds.
+  //                                Should be -1 for normal operation, only used
+  //                                for testing.
+  // Return value                 : true if OK, false when reordered timestamps
+  bool CalculateDelay(uint32_t timestamp,
+                      int64_t* delay,
+                      int64_t currentWallClock);
+
+  // Returns the current difference between incoming timestamps
+  //
+  // Return value                 : Wrap-around compensated difference between
+  // incoming
+  //                                timestamps.
+  uint32_t CurrentTimeStampDiffMs() const;
+
+ private:
+  // Controls if the RTP timestamp counter has had a wrap around
+  // between the current and the previously received frame.
+  //
+  // Input:
+  //          - timestmap         : RTP timestamp of the current frame.
+  void CheckForWrapArounds(uint32_t timestamp);
+
+  int64_t _zeroWallClock;  // Local timestamp of the first video packet received
+  int32_t _wrapArounds;    // Number of wrapArounds detected
+  // The previous timestamp passed to the delay estimate
+  uint32_t _prevTimestamp;
+  // The previous wall clock timestamp used by the delay estimate
+  int64_t _prevWallClock;
+  // Wrap-around compensated difference between incoming timestamps
+  int64_t _dTS;
+};
+
+}  // namespace webrtc
+
+#endif  // WEBRTC_MODULES_VIDEO_CODING_INTER_FRAME_DELAY_H_