1 /* 2 * Copyright (c) 2018 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 #include "modules/congestion_controller/rtp/control_handler.h" 12 13 #include <algorithm> 14 #include <vector> 15 16 #include "api/units/data_rate.h" 17 #include "rtc_base/logging.h" 18 #include "rtc_base/numerics/safe_conversions.h" 19 #include "rtc_base/numerics/safe_minmax.h" 20 #include "system_wrappers/include/field_trial.h" 21 22 namespace webrtc { 23 namespace { 24 25 // By default, pacer emergency stops encoder when buffer reaches a high level. IsPacerEmergencyStopDisabled()26bool IsPacerEmergencyStopDisabled() { 27 return field_trial::IsEnabled("WebRTC-DisablePacerEmergencyStop"); 28 } 29 30 } // namespace CongestionControlHandler()31CongestionControlHandler::CongestionControlHandler() 32 : disable_pacer_emergency_stop_(IsPacerEmergencyStopDisabled()) { 33 sequenced_checker_.Detach(); 34 } 35 ~CongestionControlHandler()36CongestionControlHandler::~CongestionControlHandler() {} 37 SetTargetRate(TargetTransferRate new_target_rate)38void CongestionControlHandler::SetTargetRate( 39 TargetTransferRate new_target_rate) { 40 RTC_DCHECK_RUN_ON(&sequenced_checker_); 41 RTC_CHECK(new_target_rate.at_time.IsFinite()); 42 last_incoming_ = new_target_rate; 43 } 44 SetNetworkAvailability(bool network_available)45void CongestionControlHandler::SetNetworkAvailability(bool network_available) { 46 RTC_DCHECK_RUN_ON(&sequenced_checker_); 47 network_available_ = network_available; 48 } 49 SetPacerQueue(TimeDelta expected_queue_time)50void CongestionControlHandler::SetPacerQueue(TimeDelta expected_queue_time) { 51 RTC_DCHECK_RUN_ON(&sequenced_checker_); 52 pacer_expected_queue_ms_ = expected_queue_time.ms(); 53 } 54 GetUpdate()55absl::optional<TargetTransferRate> CongestionControlHandler::GetUpdate() { 56 RTC_DCHECK_RUN_ON(&sequenced_checker_); 57 if (!last_incoming_.has_value()) 58 return absl::nullopt; 59 TargetTransferRate new_outgoing = *last_incoming_; 60 DataRate log_target_rate = new_outgoing.target_rate; 61 bool pause_encoding = false; 62 if (!network_available_) { 63 pause_encoding = true; 64 } else if (!disable_pacer_emergency_stop_ && 65 pacer_expected_queue_ms_ > PacedSender::kMaxQueueLengthMs) { 66 pause_encoding = true; 67 } 68 if (pause_encoding) 69 new_outgoing.target_rate = DataRate::Zero(); 70 if (!last_reported_ || 71 last_reported_->target_rate != new_outgoing.target_rate || 72 (!new_outgoing.target_rate.IsZero() && 73 (last_reported_->network_estimate.loss_rate_ratio != 74 new_outgoing.network_estimate.loss_rate_ratio || 75 last_reported_->network_estimate.round_trip_time != 76 new_outgoing.network_estimate.round_trip_time))) { 77 if (encoder_paused_in_last_report_ != pause_encoding) 78 RTC_LOG(LS_INFO) << "Bitrate estimate state changed, BWE: " 79 << ToString(log_target_rate) << "."; 80 encoder_paused_in_last_report_ = pause_encoding; 81 last_reported_ = new_outgoing; 82 return new_outgoing; 83 } 84 return absl::nullopt; 85 } 86 87 } // namespace webrtc 88