1 /* 2 * Copyright (c) 2014 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 #ifndef WEBRTC_MODULES_RTP_RTCP_INCLUDE_REMOTE_NTP_TIME_ESTIMATOR_H_ 12 #define WEBRTC_MODULES_RTP_RTCP_INCLUDE_REMOTE_NTP_TIME_ESTIMATOR_H_ 13 14 #include "webrtc/base/scoped_ptr.h" 15 #include "webrtc/system_wrappers/include/rtp_to_ntp.h" 16 17 namespace webrtc { 18 19 class Clock; 20 class TimestampExtrapolator; 21 22 // RemoteNtpTimeEstimator can be used to estimate a given RTP timestamp's NTP 23 // time in local timebase. 24 // Note that it needs to be trained with at least 2 RTCP SR (by calling 25 // |UpdateRtcpTimestamp|) before it can be used. 26 class RemoteNtpTimeEstimator { 27 public: 28 explicit RemoteNtpTimeEstimator(Clock* clock); 29 30 ~RemoteNtpTimeEstimator(); 31 32 // Updates the estimator with round trip time |rtt|, NTP seconds |ntp_secs|, 33 // NTP fraction |ntp_frac| and RTP timestamp |rtcp_timestamp|. 34 bool UpdateRtcpTimestamp(int64_t rtt, uint32_t ntp_secs, uint32_t ntp_frac, 35 uint32_t rtp_timestamp); 36 37 // Estimates the NTP timestamp in local timebase from |rtp_timestamp|. 38 // Returns the NTP timestamp in ms when success. -1 if failed. 39 int64_t Estimate(uint32_t rtp_timestamp); 40 41 private: 42 Clock* clock_; 43 rtc::scoped_ptr<TimestampExtrapolator> ts_extrapolator_; 44 RtcpList rtcp_list_; 45 int64_t last_timing_log_ms_; 46 RTC_DISALLOW_COPY_AND_ASSIGN(RemoteNtpTimeEstimator); 47 }; 48 49 } // namespace webrtc 50 51 #endif // WEBRTC_MODULES_RTP_RTCP_INCLUDE_REMOTE_NTP_TIME_ESTIMATOR_H_ 52
