chromium/third_party/webrtc/modules/rtp_rtcp/source/remote_ntp_time_estimator.cc

/*
 *  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.
 */

#include "modules/rtp_rtcp/include/remote_ntp_time_estimator.h"

#include <cstdint>

#include "modules/rtp_rtcp/source/ntp_time_util.h"
#include "rtc_base/logging.h"
#include "system_wrappers/include/clock.h"
#include "system_wrappers/include/ntp_time.h"

namespace webrtc {

namespace {

constexpr int kMinimumNumberOfSamples = …;
constexpr TimeDelta kTimingLogInterval = …;
constexpr int kClocksOffsetSmoothingWindow = …;

// Subtracts two NtpTime values keeping maximum precision.
int64_t Subtract(NtpTime minuend, NtpTime subtrahend) { … }

NtpTime Add(NtpTime lhs, int64_t rhs) { … }

}  // namespace

// TODO(wu): Refactor this class so that it can be shared with
// vie_sync_module.cc.
RemoteNtpTimeEstimator::RemoteNtpTimeEstimator(Clock* clock)
    : … { … }

bool RemoteNtpTimeEstimator::UpdateRtcpTimestamp(TimeDelta rtt,
                                                 NtpTime sender_send_time,
                                                 uint32_t rtp_timestamp) { … }

NtpTime RemoteNtpTimeEstimator::EstimateNtp(uint32_t rtp_timestamp) { … }

absl::optional<int64_t>
RemoteNtpTimeEstimator::EstimateRemoteToLocalClockOffset() { … }

}  // namespace webrtc