modules/rtp_rtcp/source/capture_clock_offset_updater.cc

/*
 *  Copyright (c) 2021 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/source/capture_clock_offset_updater.h"

#include <cstdint>
#include <optional>

#include "api/units/time_delta.h"
#include "system_wrappers/include/ntp_time.h"

namespace webrtc {

std::optional<int64_t>
CaptureClockOffsetUpdater::AdjustEstimatedCaptureClockOffset(
    std::optional<int64_t> remote_capture_clock_offset) const {
  if (remote_capture_clock_offset == std::nullopt ||
      remote_to_local_clock_offset_ == std::nullopt) {
    return std::nullopt;
  }

  // Do calculations as "unsigned" to make overflows deterministic.
  return static_cast<uint64_t>(*remote_capture_clock_offset) +
         static_cast<uint64_t>(*remote_to_local_clock_offset_);
}

std::optional<TimeDelta> CaptureClockOffsetUpdater::ConvertsToTimeDela(
    std::optional<int64_t> q32x32) {
  if (q32x32 == std::nullopt) {
    return std::nullopt;
  }
  return TimeDelta::Millis(Q32x32ToInt64Ms(*q32x32));
}

void CaptureClockOffsetUpdater::SetRemoteToLocalClockOffset(
    std::optional<int64_t> offset_q32x32) {
  remote_to_local_clock_offset_ = offset_q32x32;
}

}  // namespace webrtc