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Diffstat (limited to 'third_party/libwebrtc/call/receive_time_calculator.h')
-rw-r--r-- | third_party/libwebrtc/call/receive_time_calculator.h | 63 |
1 files changed, 63 insertions, 0 deletions
diff --git a/third_party/libwebrtc/call/receive_time_calculator.h b/third_party/libwebrtc/call/receive_time_calculator.h new file mode 100644 index 0000000000..57ba331844 --- /dev/null +++ b/third_party/libwebrtc/call/receive_time_calculator.h @@ -0,0 +1,63 @@ +/* + * Copyright (c) 2018 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 CALL_RECEIVE_TIME_CALCULATOR_H_ +#define CALL_RECEIVE_TIME_CALCULATOR_H_ + +#include <stdint.h> + +#include <memory> + +#include "api/field_trials_view.h" +#include "api/units/time_delta.h" +#include "rtc_base/experiments/field_trial_parser.h" + +namespace webrtc { + +struct ReceiveTimeCalculatorConfig { + explicit ReceiveTimeCalculatorConfig(const FieldTrialsView& field_trials); + ReceiveTimeCalculatorConfig(const ReceiveTimeCalculatorConfig&); + ReceiveTimeCalculatorConfig& operator=(const ReceiveTimeCalculatorConfig&) = + default; + ~ReceiveTimeCalculatorConfig(); + FieldTrialParameter<TimeDelta> max_packet_time_repair; + FieldTrialParameter<TimeDelta> stall_threshold; + FieldTrialParameter<TimeDelta> tolerance; + FieldTrialParameter<TimeDelta> max_stall; +}; + +// The receive time calculator serves the purpose of combining packet time +// stamps with a safely incremental clock. This assumes that the packet time +// stamps are based on lower layer timestamps that have more accurate time +// increments since they are based on the exact receive time. They might +// however, have large jumps due to clock resets in the system. To compensate +// this they are combined with a safe clock source that is guaranteed to be +// consistent, but it will not be able to measure the exact time when a packet +// is received. +class ReceiveTimeCalculator { + public: + static std::unique_ptr<ReceiveTimeCalculator> CreateFromFieldTrial( + const FieldTrialsView& field_trials); + explicit ReceiveTimeCalculator(const FieldTrialsView& field_trials); + int64_t ReconcileReceiveTimes(int64_t packet_time_us_, + int64_t system_time_us_, + int64_t safe_time_us_); + + private: + int64_t last_corrected_time_us_ = -1; + int64_t last_packet_time_us_ = -1; + int64_t last_system_time_us_ = -1; + int64_t last_safe_time_us_ = -1; + int64_t total_system_time_passed_us_ = 0; + int64_t static_clock_offset_us_ = 0; + int64_t small_reset_during_stall_ = false; + ReceiveTimeCalculatorConfig config_; +}; +} // namespace webrtc +#endif // CALL_RECEIVE_TIME_CALCULATOR_H_ |