| /* |
| * Copyright (c) 2024 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 MODULES_REMOTE_BITRATE_ESTIMATOR_CONGESTION_CONTROL_FEEDBACK_GENERATOR_H_ |
| #define MODULES_REMOTE_BITRATE_ESTIMATOR_CONGESTION_CONTROL_FEEDBACK_GENERATOR_H_ |
| |
| #include <cstdint> |
| #include <map> |
| #include <optional> |
| |
| #include "api/environment/environment.h" |
| #include "api/sequence_checker.h" |
| #include "api/units/data_rate.h" |
| #include "api/units/data_size.h" |
| #include "api/units/time_delta.h" |
| #include "api/units/timestamp.h" |
| #include "modules/remote_bitrate_estimator/congestion_control_feedback_tracker.h" |
| #include "modules/remote_bitrate_estimator/rtp_transport_feedback_generator.h" |
| #include "modules/rtp_rtcp/source/rtp_packet_received.h" |
| #include "rtc_base/experiments/field_trial_parser.h" |
| |
| namespace webrtc { |
| |
| // The class is responsible for generating RTCP feedback packets based on |
| // incoming media packets. Feedback format will comply with RFC 8888. |
| // https://datatracker.ietf.org/doc/rfc8888/ |
| |
| // Feedback should not use more than 5% of the configured send bandwidth |
| // estimate. Min and max duration between feedback is configurable using field |
| // trials, but per default, min is 25ms and max is 250ms. |
| // If possible, given the other constraints, feedback will be sent when a packet |
| // with marker bit is received in order to provide feedback as soon as possible |
| // after receiving a complete video frame. If no packet with marker bit is |
| // received, feedback can be delayed up to 25ms after the first packet since the |
| // last sent feedback. On good networks, this means that a sender may receive |
| // feedback for every sent frame. |
| class CongestionControlFeedbackGenerator |
| : public RtpTransportFeedbackGenerator { |
| public: |
| CongestionControlFeedbackGenerator( |
| const Environment& env, |
| RtpTransportFeedbackGenerator::RtcpSender feedback_sender); |
| ~CongestionControlFeedbackGenerator() = default; |
| |
| void OnReceivedPacket(const RtpPacketReceived& packet) override; |
| |
| void OnSendBandwidthEstimateChanged(DataRate estimate) override; |
| |
| TimeDelta Process(Timestamp now) override; |
| |
| void SetTransportOverhead(DataSize overhead_per_packet) override; |
| |
| private: |
| Timestamp NextFeedbackTime() const RTC_RUN_ON(sequence_checker_); |
| |
| void SendFeedback(Timestamp now) RTC_RUN_ON(sequence_checker_); |
| |
| void CalculateNextPossibleSendTime(DataSize feedback_size, Timestamp now) |
| RTC_RUN_ON(sequence_checker_); |
| |
| const Environment env_; |
| SequenceChecker sequence_checker_; |
| const RtcpSender rtcp_sender_; |
| |
| FieldTrialParameter<TimeDelta> min_time_between_feedback_; |
| FieldTrialParameter<TimeDelta> max_time_to_wait_for_packet_with_marker_; |
| FieldTrialParameter<TimeDelta> max_time_between_feedback_; |
| |
| DataRate max_feedback_rate_ = DataRate::KilobitsPerSec(1000); |
| DataSize packet_overhead_ = DataSize::Zero(); |
| DataSize send_rate_debt_ = DataSize::Zero(); |
| |
| std::map</*ssrc=*/uint32_t, CongestionControlFeedbackTracker> |
| feedback_trackers_; |
| |
| // std::vector<PacketInfo> packets_; |
| Timestamp last_feedback_sent_time_ = Timestamp::Zero(); |
| std::optional<Timestamp> first_arrival_time_since_feedback_; |
| bool marker_bit_seen_ = false; |
| Timestamp next_possible_feedback_send_time_ = Timestamp::Zero(); |
| }; |
| |
| } // namespace webrtc |
| |
| #endif // MODULES_REMOTE_BITRATE_ESTIMATOR_CONGESTION_CONTROL_FEEDBACK_GENERATOR_H_ |