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diff --git a/webrtc/modules/rtp_rtcp/include/remote_ntp_time_estimator.h b/webrtc/modules/rtp_rtcp/include/remote_ntp_time_estimator.h
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+++ b/webrtc/modules/rtp_rtcp/include/remote_ntp_time_estimator.h
@@ -0,0 +1,51 @@
+/*
+ *  Copyright (c) 2014 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_RTP_RTCP_INCLUDE_REMOTE_NTP_TIME_ESTIMATOR_H_
+#define WEBRTC_MODULES_RTP_RTCP_INCLUDE_REMOTE_NTP_TIME_ESTIMATOR_H_
+
+#include "webrtc/base/scoped_ptr.h"
+#include "webrtc/system_wrappers/include/rtp_to_ntp.h"
+
+namespace webrtc {
+
+class Clock;
+class TimestampExtrapolator;
+
+// RemoteNtpTimeEstimator can be used to estimate a given RTP timestamp's NTP
+// time in local timebase.
+// Note that it needs to be trained with at least 2 RTCP SR (by calling
+// |UpdateRtcpTimestamp|) before it can be used.
+class RemoteNtpTimeEstimator {
+ public:
+  explicit RemoteNtpTimeEstimator(Clock* clock);
+
+  ~RemoteNtpTimeEstimator();
+
+  // Updates the estimator with round trip time |rtt|, NTP seconds |ntp_secs|,
+  // NTP fraction |ntp_frac| and RTP timestamp |rtcp_timestamp|.
+  bool UpdateRtcpTimestamp(int64_t rtt, uint32_t ntp_secs, uint32_t ntp_frac,
+                           uint32_t rtp_timestamp);
+
+  // Estimates the NTP timestamp in local timebase from |rtp_timestamp|.
+  // Returns the NTP timestamp in ms when success. -1 if failed.
+  int64_t Estimate(uint32_t rtp_timestamp);
+
+ private:
+  Clock* clock_;
+  rtc::scoped_ptr<TimestampExtrapolator> ts_extrapolator_;
+  RtcpList rtcp_list_;
+  int64_t last_timing_log_ms_;
+  RTC_DISALLOW_COPY_AND_ASSIGN(RemoteNtpTimeEstimator);
+};
+
+}  // namespace webrtc
+
+#endif  // WEBRTC_MODULES_RTP_RTCP_INCLUDE_REMOTE_NTP_TIME_ESTIMATOR_H_