Adding upstream version 124.0.1.upstream/124.0.1

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

14 files changed, 1327 insertions, 0 deletions

diff --git a/third_party/libwebrtc/modules/rtp_rtcp/include/flexfec_receiver.h b/third_party/libwebrtc/modules/rtp_rtcp/include/flexfec_receiver.h
new file mode 100644
index 0000000000..b6a33882d1
--- /dev/null
+++ b/third_party/libwebrtc/modules/rtp_rtcp/include/flexfec_receiver.h
@@ -0,0 +1,82 @@
+/*
+ *  Copyright (c) 2016 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_RTP_RTCP_INCLUDE_FLEXFEC_RECEIVER_H_
+#define MODULES_RTP_RTCP_INCLUDE_FLEXFEC_RECEIVER_H_
+
+#include <stdint.h>
+
+#include <memory>
+
+#include "api/sequence_checker.h"
+#include "api/units/timestamp.h"
+#include "modules/rtp_rtcp/include/recovered_packet_receiver.h"
+#include "modules/rtp_rtcp/source/forward_error_correction.h"
+#include "modules/rtp_rtcp/source/rtp_packet_received.h"
+#include "modules/rtp_rtcp/source/ulpfec_receiver.h"
+#include "rtc_base/system/no_unique_address.h"
+#include "rtc_base/thread_annotations.h"
+
+namespace webrtc {
+
+class Clock;
+
+class FlexfecReceiver {
+ public:
+  /* Mozilla: Avoid this since it could use GetRealTimeClock().
+  FlexfecReceiver(uint32_t ssrc,
+                  uint32_t protected_media_ssrc,
+                  RecoveredPacketReceiver* recovered_packet_receiver);
+   */
+  FlexfecReceiver(Clock* clock,
+                  uint32_t ssrc,
+                  uint32_t protected_media_ssrc,
+                  RecoveredPacketReceiver* recovered_packet_receiver);
+  ~FlexfecReceiver();
+
+  // Inserts a received packet (can be either media or FlexFEC) into the
+  // internal buffer, and sends the received packets to the erasure code.
+  // All newly recovered packets are sent back through the callback.
+  void OnRtpPacket(const RtpPacketReceived& packet);
+
+  // Returns a counter describing the added and recovered packets.
+  FecPacketCounter GetPacketCounter() const;
+
+  // Protected to aid testing.
+ protected:
+  std::unique_ptr<ForwardErrorCorrection::ReceivedPacket> AddReceivedPacket(
+      const RtpPacketReceived& packet);
+  void ProcessReceivedPacket(
+      const ForwardErrorCorrection::ReceivedPacket& received_packet);
+
+ private:
+  // Config.
+  const uint32_t ssrc_;
+  const uint32_t protected_media_ssrc_;
+
+  // Erasure code interfacing and callback.
+  std::unique_ptr<ForwardErrorCorrection> erasure_code_
+      RTC_GUARDED_BY(sequence_checker_);
+  ForwardErrorCorrection::RecoveredPacketList recovered_packets_
+      RTC_GUARDED_BY(sequence_checker_);
+  RecoveredPacketReceiver* const recovered_packet_receiver_;
+
+  // Logging and stats.
+  Clock* const clock_;
+  Timestamp last_recovered_packet_ RTC_GUARDED_BY(sequence_checker_) =
+      Timestamp::MinusInfinity();
+  FecPacketCounter packet_counter_ RTC_GUARDED_BY(sequence_checker_);
+
+  RTC_NO_UNIQUE_ADDRESS SequenceChecker sequence_checker_;
+};
+
+}  // namespace webrtc
+
+#endif  // MODULES_RTP_RTCP_INCLUDE_FLEXFEC_RECEIVER_H_
diff --git a/third_party/libwebrtc/modules/rtp_rtcp/include/flexfec_sender.h b/third_party/libwebrtc/modules/rtp_rtcp/include/flexfec_sender.h
new file mode 100644
index 0000000000..8f21ab7517
--- /dev/null
+++ b/third_party/libwebrtc/modules/rtp_rtcp/include/flexfec_sender.h
@@ -0,0 +1,104 @@
+/*
+ *  Copyright (c) 2016 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_RTP_RTCP_INCLUDE_FLEXFEC_SENDER_H_
+#define MODULES_RTP_RTCP_INCLUDE_FLEXFEC_SENDER_H_
+
+#include <memory>
+#include <string>
+#include <vector>
+
+#include "absl/strings/string_view.h"
+#include "api/array_view.h"
+#include "api/rtp_parameters.h"
+#include "api/units/timestamp.h"
+#include "modules/rtp_rtcp/include/rtp_header_extension_map.h"
+#include "modules/rtp_rtcp/include/rtp_rtcp_defines.h"
+#include "modules/rtp_rtcp/source/rtp_header_extension_size.h"
+#include "modules/rtp_rtcp/source/ulpfec_generator.h"
+#include "modules/rtp_rtcp/source/video_fec_generator.h"
+#include "rtc_base/bitrate_tracker.h"
+#include "rtc_base/random.h"
+#include "rtc_base/synchronization/mutex.h"
+
+namespace webrtc {
+
+class Clock;
+class RtpPacketToSend;
+
+// Note that this class is not thread safe, and thus requires external
+// synchronization. Currently, this is done using the lock in PayloadRouter.
+
+class FlexfecSender : public VideoFecGenerator {
+ public:
+  FlexfecSender(int payload_type,
+                uint32_t ssrc,
+                uint32_t protected_media_ssrc,
+                absl::string_view mid,
+                const std::vector<RtpExtension>& rtp_header_extensions,
+                rtc::ArrayView<const RtpExtensionSize> extension_sizes,
+                const RtpState* rtp_state,
+                Clock* clock);
+  ~FlexfecSender();
+
+  FecType GetFecType() const override {
+    return VideoFecGenerator::FecType::kFlexFec;
+  }
+  absl::optional<uint32_t> FecSsrc() override { return ssrc_; }
+
+  // Sets the FEC rate, max frames sent before FEC packets are sent,
+  // and what type of generator matrices are used.
+  void SetProtectionParameters(const FecProtectionParams& delta_params,
+                               const FecProtectionParams& key_params) override;
+
+  // Adds a media packet to the internal buffer. When enough media packets
+  // have been added, the FEC packets are generated and stored internally.
+  // These FEC packets are then obtained by calling GetFecPackets().
+  void AddPacketAndGenerateFec(const RtpPacketToSend& packet) override;
+
+  // Returns generated FlexFEC packets.
+  std::vector<std::unique_ptr<RtpPacketToSend>> GetFecPackets() override;
+
+  // Returns the overhead, per packet, for FlexFEC.
+  size_t MaxPacketOverhead() const override;
+
+  DataRate CurrentFecRate() const override;
+
+  // Only called on the VideoSendStream queue, after operation has shut down.
+  absl::optional<RtpState> GetRtpState() override;
+
+ private:
+  // Utility.
+  Clock* const clock_;
+  Random random_;
+  Timestamp last_generated_packet_ = Timestamp::MinusInfinity();
+
+  // Config.
+  const int payload_type_;
+  const uint32_t timestamp_offset_;
+  const uint32_t ssrc_;
+  const uint32_t protected_media_ssrc_;
+  // MID value to send in the MID header extension.
+  const std::string mid_;
+  // Sequence number of next packet to generate.
+  uint16_t seq_num_;
+
+  // Implementation.
+  UlpfecGenerator ulpfec_generator_;
+  const RtpHeaderExtensionMap rtp_header_extension_map_;
+  const size_t header_extensions_size_;
+
+  mutable Mutex mutex_;
+  BitrateTracker fec_bitrate_ RTC_GUARDED_BY(mutex_);
+};
+
+}  // namespace webrtc
+
+#endif  // MODULES_RTP_RTCP_INCLUDE_FLEXFEC_SENDER_H_
diff --git a/third_party/libwebrtc/modules/rtp_rtcp/include/receive_statistics.h b/third_party/libwebrtc/modules/rtp_rtcp/include/receive_statistics.h
new file mode 100644
index 0000000000..827fd3a7a8
--- /dev/null
+++ b/third_party/libwebrtc/modules/rtp_rtcp/include/receive_statistics.h
@@ -0,0 +1,83 @@
+/*
+ *  Copyright (c) 2013 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_RTP_RTCP_INCLUDE_RECEIVE_STATISTICS_H_
+#define MODULES_RTP_RTCP_INCLUDE_RECEIVE_STATISTICS_H_
+
+#include <map>
+#include <memory>
+#include <vector>
+
+#include "absl/types/optional.h"
+#include "call/rtp_packet_sink_interface.h"
+#include "modules/rtp_rtcp/include/rtcp_statistics.h"
+#include "modules/rtp_rtcp/include/rtp_rtcp_defines.h"
+#include "modules/rtp_rtcp/source/rtcp_packet/report_block.h"
+
+namespace webrtc {
+
+class Clock;
+
+class ReceiveStatisticsProvider {
+ public:
+  virtual ~ReceiveStatisticsProvider() = default;
+  // Collects receive statistic in a form of rtcp report blocks.
+  // Returns at most `max_blocks` report blocks.
+  virtual std::vector<rtcp::ReportBlock> RtcpReportBlocks(
+      size_t max_blocks) = 0;
+};
+
+class StreamStatistician {
+ public:
+  virtual ~StreamStatistician();
+
+  virtual RtpReceiveStats GetStats() const = 0;
+
+  // Returns average over the stream life time.
+  virtual absl::optional<int> GetFractionLostInPercent() const = 0;
+
+  // TODO(bugs.webrtc.org/10679): Delete, migrate users to the above GetStats
+  // method (and extend RtpReceiveStats if needed).
+  // Gets receive stream data counters.
+  virtual StreamDataCounters GetReceiveStreamDataCounters() const = 0;
+
+  virtual uint32_t BitrateReceived() const = 0;
+};
+
+class ReceiveStatistics : public ReceiveStatisticsProvider,
+                          public RtpPacketSinkInterface {
+ public:
+  ~ReceiveStatistics() override = default;
+
+  // Returns a thread-safe instance of ReceiveStatistics.
+  // https://chromium.googlesource.com/chromium/src/+/lkgr/docs/threading_and_tasks.md#threading-lexicon
+  static std::unique_ptr<ReceiveStatistics> Create(Clock* clock);
+  // Returns a thread-compatible instance of ReceiveStatistics.
+  static std::unique_ptr<ReceiveStatistics> CreateThreadCompatible(
+      Clock* clock);
+
+  // Returns a pointer to the statistician of an ssrc.
+  virtual StreamStatistician* GetStatistician(uint32_t ssrc) const = 0;
+
+  // TODO(bugs.webrtc.org/10669): Deprecated, delete as soon as downstream
+  // projects are updated. This method sets the max reordering threshold of all
+  // current and future streams.
+  virtual void SetMaxReorderingThreshold(int max_reordering_threshold) = 0;
+
+  // Sets the max reordering threshold in number of packets.
+  virtual void SetMaxReorderingThreshold(uint32_t ssrc,
+                                         int max_reordering_threshold) = 0;
+  // Detect retransmissions, enabling updates of the retransmitted counters. The
+  // default is false.
+  virtual void EnableRetransmitDetection(uint32_t ssrc, bool enable) = 0;
+};
+
+}  // namespace webrtc
+#endif  // MODULES_RTP_RTCP_INCLUDE_RECEIVE_STATISTICS_H_
diff --git a/third_party/libwebrtc/modules/rtp_rtcp/include/recovered_packet_receiver.h b/third_party/libwebrtc/modules/rtp_rtcp/include/recovered_packet_receiver.h
new file mode 100644
index 0000000000..4e92c486e2
--- /dev/null
+++ b/third_party/libwebrtc/modules/rtp_rtcp/include/recovered_packet_receiver.h
@@ -0,0 +1,30 @@
+/*
+ *  Copyright (c) 2022 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_RTP_RTCP_INCLUDE_RECOVERED_PACKET_RECEIVER_H_
+#define MODULES_RTP_RTCP_INCLUDE_RECOVERED_PACKET_RECEIVER_H_
+
+#include "modules/rtp_rtcp/source/rtp_packet_received.h"
+#include "rtc_base/checks.h"
+
+namespace webrtc {
+
+// Callback interface for packets recovered by FlexFEC or ULPFEC. In
+// the FlexFEC case, the implementation should be able to demultiplex
+// the recovered RTP packets based on SSRC.
+class RecoveredPacketReceiver {
+ public:
+  virtual void OnRecoveredPacket(const RtpPacketReceived& packet) = 0;
+
+ protected:
+  virtual ~RecoveredPacketReceiver() = default;
+};
+
+}  // namespace webrtc
+#endif  // MODULES_RTP_RTCP_INCLUDE_RECOVERED_PACKET_RECEIVER_H_
diff --git a/third_party/libwebrtc/modules/rtp_rtcp/include/remote_ntp_time_estimator.h b/third_party/libwebrtc/modules/rtp_rtcp/include/remote_ntp_time_estimator.h
new file mode 100644
index 0000000000..01d0c85f94
--- /dev/null
+++ b/third_party/libwebrtc/modules/rtp_rtcp/include/remote_ntp_time_estimator.h
@@ -0,0 +1,74 @@
+/*
+ *  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.
+ */
+
+#ifndef MODULES_RTP_RTCP_INCLUDE_REMOTE_NTP_TIME_ESTIMATOR_H_
+#define MODULES_RTP_RTCP_INCLUDE_REMOTE_NTP_TIME_ESTIMATOR_H_
+
+#include <stdint.h>
+
+#include "absl/types/optional.h"
+#include "api/units/time_delta.h"
+#include "api/units/timestamp.h"
+#include "rtc_base/numerics/moving_percentile_filter.h"
+#include "system_wrappers/include/rtp_to_ntp_estimator.h"
+
+namespace webrtc {
+
+class Clock;
+
+// RemoteNtpTimeEstimator can be used to estimate a given RTP timestamp's NTP
+// time in local timebase.
+// Note that it needs to be trained with at least 2 RTCP SR (by calling
+// `UpdateRtcpTimestamp`) before it can be used.
+class RemoteNtpTimeEstimator {
+ public:
+  explicit RemoteNtpTimeEstimator(Clock* clock);
+  RemoteNtpTimeEstimator(const RemoteNtpTimeEstimator&) = delete;
+  RemoteNtpTimeEstimator& operator=(const RemoteNtpTimeEstimator&) = delete;
+  ~RemoteNtpTimeEstimator() = default;
+
+  // Updates the estimator with round trip time `rtt` and
+  // new NTP time <-> RTP timestamp mapping from an RTCP sender report.
+  bool UpdateRtcpTimestamp(TimeDelta rtt,
+                           NtpTime sender_send_time,
+                           uint32_t rtp_timestamp);
+
+  // Estimates the NTP timestamp in local timebase from `rtp_timestamp`.
+  // Returns the NTP timestamp in ms when success. -1 if failed.
+  int64_t Estimate(uint32_t rtp_timestamp) {
+    NtpTime ntp_time = EstimateNtp(rtp_timestamp);
+    if (!ntp_time.Valid()) {
+      return -1;
+    }
+    return ntp_time.ToMs();
+  }
+
+  // Estimates the NTP timestamp in local timebase from `rtp_timestamp`.
+  // Returns invalid NtpTime (i.e. NtpTime(0)) on failure.
+  NtpTime EstimateNtp(uint32_t rtp_timestamp);
+
+  // Estimates the offset between the remote clock and the
+  // local one. This is equal to local NTP clock - remote NTP clock.
+  // The offset is returned in ntp time resolution, i.e. 1/2^32 sec ~= 0.2 ns.
+  // Returns nullopt on failure.
+  absl::optional<int64_t> EstimateRemoteToLocalClockOffset();
+
+ private:
+  Clock* clock_;
+  // Offset is measured with the same precision as NtpTime: in 1/2^32 seconds ~=
+  // 0.2 ns.
+  MovingMedianFilter<int64_t> ntp_clocks_offset_estimator_;
+  RtpToNtpEstimator rtp_to_ntp_;
+  Timestamp last_timing_log_ = Timestamp::MinusInfinity();
+};
+
+}  // namespace webrtc
+
+#endif  // MODULES_RTP_RTCP_INCLUDE_REMOTE_NTP_TIME_ESTIMATOR_H_
diff --git a/third_party/libwebrtc/modules/rtp_rtcp/include/report_block_data.cc b/third_party/libwebrtc/modules/rtp_rtcp/include/report_block_data.cc
new file mode 100644
index 0000000000..0d4fed043f
--- /dev/null
+++ b/third_party/libwebrtc/modules/rtp_rtcp/include/report_block_data.cc
@@ -0,0 +1,42 @@
+/*
+ *  Copyright 2019 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/report_block_data.h"
+
+#include "rtc_base/checks.h"
+
+namespace webrtc {
+
+TimeDelta ReportBlockData::jitter(int rtp_clock_rate_hz) const {
+  RTC_DCHECK_GT(rtp_clock_rate_hz, 0);
+  // Conversion to TimeDelta and division are swapped to avoid conversion
+  // to/from floating point types.
+  return TimeDelta::Seconds(jitter()) / rtp_clock_rate_hz;
+}
+
+void ReportBlockData::SetReportBlock(uint32_t sender_ssrc,
+                                     const rtcp::ReportBlock& report_block,
+                                     Timestamp report_block_timestamp_utc) {
+  sender_ssrc_ = sender_ssrc;
+  source_ssrc_ = report_block.source_ssrc();
+  fraction_lost_raw_ = report_block.fraction_lost();
+  cumulative_lost_ = report_block.cumulative_lost();
+  extended_highest_sequence_number_ = report_block.extended_high_seq_num();
+  jitter_ = report_block.jitter();
+  report_block_timestamp_utc_ = report_block_timestamp_utc;
+}
+
+void ReportBlockData::AddRoundTripTimeSample(TimeDelta rtt) {
+  last_rtt_ = rtt;
+  sum_rtt_ += rtt;
+  ++num_rtts_;
+}
+
+}  // namespace webrtc
diff --git a/third_party/libwebrtc/modules/rtp_rtcp/include/report_block_data.h b/third_party/libwebrtc/modules/rtp_rtcp/include/report_block_data.h
new file mode 100644
index 0000000000..9987fc46b9
--- /dev/null
+++ b/third_party/libwebrtc/modules/rtp_rtcp/include/report_block_data.h
@@ -0,0 +1,123 @@
+/*
+ *  Copyright 2019 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_RTP_RTCP_INCLUDE_REPORT_BLOCK_DATA_H_
+#define MODULES_RTP_RTCP_INCLUDE_REPORT_BLOCK_DATA_H_
+
+#include "api/units/time_delta.h"
+#include "api/units/timestamp.h"
+#include "modules/rtp_rtcp/source/rtcp_packet/report_block.h"
+
+namespace webrtc {
+
+// Represents fields and derived information received in RTCP report block
+// attached to RTCP sender report or RTCP receiver report, as described in
+// https://www.rfc-editor.org/rfc/rfc3550#section-6.4.1
+class ReportBlockData {
+ public:
+  ReportBlockData() = default;
+
+  ReportBlockData(const ReportBlockData&) = default;
+  ReportBlockData& operator=(const ReportBlockData&) = default;
+
+  // The SSRC identifier for the originator of this report block,
+  // i.e. remote receiver of the RTP stream.
+  uint32_t sender_ssrc() const { return sender_ssrc_; }
+
+  // The SSRC identifier of the source to which the information in this
+  // reception report block pertains, i.e. local sender of the RTP stream.
+  uint32_t source_ssrc() const { return source_ssrc_; }
+
+  // The fraction of RTP data packets from 'source_ssrc()' lost since the
+  // previous report block was sent.
+  // Fraction loss in range [0.0, 1.0].
+  float fraction_lost() const { return fraction_lost_raw() / 256.0; }
+
+  // Fraction loss as was written in the raw packet: range is [0, 255] where 0
+  // represents no loss, and 255 represents 99.6% loss (255/256 * 100%).
+  uint8_t fraction_lost_raw() const { return fraction_lost_raw_; }
+
+  // The total number of RTP data packets from 'source_ssrc()' that have been
+  // lost since the beginning of reception.  This number is defined to be the
+  // number of packets expected less the number of packets actually received,
+  // where the number of packets received includes any which are late or
+  // duplicates. Thus, packets that arrive late are not counted as lost, and the
+  // loss may be negative if there are duplicates.
+  int cumulative_lost() const { return cumulative_lost_; }
+
+  // The low 16 bits contain the highest sequence number received in an RTP data
+  // packet from 'source_ssrc()', and the most significant 16 bits extend that
+  // sequence number with the corresponding count of sequence number cycles.
+  uint32_t extended_highest_sequence_number() const {
+    return extended_highest_sequence_number_;
+  }
+
+  // An estimate of the statistical variance of the RTP data packet interarrival
+  // time, measured in RTP timestamp units. The interarrival jitter J is defined
+  // to be the mean deviation (smoothed absolute value) of the difference D in
+  // packet spacing at the receiver compared to the sender for a pair of
+  // packets.
+  uint32_t jitter() const { return jitter_; }
+
+  // Jitter converted to common time units.
+  TimeDelta jitter(int rtp_clock_rate_hz) const;
+
+  // Time in utc epoch (Jan 1st, 1970) the report block was received.
+  Timestamp report_block_timestamp_utc() const {
+    return report_block_timestamp_utc_;
+  }
+
+  // Round Trip Time measurments for given (sender_ssrc, source_ssrc) pair.
+  // Min, max, sum, number of measurements are since beginning of the call.
+  TimeDelta last_rtt() const { return last_rtt_; }
+  TimeDelta sum_rtts() const { return sum_rtt_; }
+  size_t num_rtts() const { return num_rtts_; }
+  bool has_rtt() const { return num_rtts_ != 0; }
+
+  void set_sender_ssrc(uint32_t ssrc) { sender_ssrc_ = ssrc; }
+  void set_source_ssrc(uint32_t ssrc) { source_ssrc_ = ssrc; }
+  void set_fraction_lost_raw(uint8_t lost) { fraction_lost_raw_ = lost; }
+  void set_cumulative_lost(int lost) { cumulative_lost_ = lost; }
+  void set_extended_highest_sequence_number(uint32_t sn) {
+    extended_highest_sequence_number_ = sn;
+  }
+  void set_jitter(uint32_t jitter) { jitter_ = jitter; }
+  void set_report_block_timestamp_utc(Timestamp arrival_time) {
+    report_block_timestamp_utc_ = arrival_time;
+  }
+
+  void SetReportBlock(uint32_t sender_ssrc,
+                      const rtcp::ReportBlock& report_block,
+                      Timestamp report_block_timestamp_utc);
+  void AddRoundTripTimeSample(TimeDelta rtt);
+
+ private:
+  uint32_t sender_ssrc_ = 0;
+  uint32_t source_ssrc_ = 0;
+  uint8_t fraction_lost_raw_ = 0;
+  int32_t cumulative_lost_ = 0;
+  uint32_t extended_highest_sequence_number_ = 0;
+  uint32_t jitter_ = 0;
+  Timestamp report_block_timestamp_utc_ = Timestamp::Zero();
+  TimeDelta last_rtt_ = TimeDelta::Zero();
+  TimeDelta sum_rtt_ = TimeDelta::Zero();
+  size_t num_rtts_ = 0;
+};
+
+class ReportBlockDataObserver {
+ public:
+  virtual ~ReportBlockDataObserver() = default;
+
+  virtual void OnReportBlockDataUpdated(ReportBlockData report_block_data) = 0;
+};
+
+}  // namespace webrtc
+
+#endif  // MODULES_RTP_RTCP_INCLUDE_REPORT_BLOCK_DATA_H_
diff --git a/third_party/libwebrtc/modules/rtp_rtcp/include/rtcp_statistics.h b/third_party/libwebrtc/modules/rtp_rtcp/include/rtcp_statistics.h
new file mode 100644
index 0000000000..6d6246d8a8
--- /dev/null
+++ b/third_party/libwebrtc/modules/rtp_rtcp/include/rtcp_statistics.h
@@ -0,0 +1,77 @@
+/*
+ *  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 MODULES_RTP_RTCP_INCLUDE_RTCP_STATISTICS_H_
+#define MODULES_RTP_RTCP_INCLUDE_RTCP_STATISTICS_H_
+
+#include <stdint.h>
+
+#include "absl/strings/string_view.h"
+
+namespace webrtc {
+
+// Statistics for RTCP packet types.
+struct RtcpPacketTypeCounter {
+  RtcpPacketTypeCounter()
+      : nack_packets(0),
+        fir_packets(0),
+        pli_packets(0),
+        nack_requests(0),
+        unique_nack_requests(0) {}
+
+  void Add(const RtcpPacketTypeCounter& other) {
+    nack_packets += other.nack_packets;
+    fir_packets += other.fir_packets;
+    pli_packets += other.pli_packets;
+    nack_requests += other.nack_requests;
+    unique_nack_requests += other.unique_nack_requests;
+  }
+
+  void Subtract(const RtcpPacketTypeCounter& other) {
+    nack_packets -= other.nack_packets;
+    fir_packets -= other.fir_packets;
+    pli_packets -= other.pli_packets;
+    nack_requests -= other.nack_requests;
+    unique_nack_requests -= other.unique_nack_requests;
+  }
+
+  int UniqueNackRequestsInPercent() const {
+    if (nack_requests == 0) {
+      return 0;
+    }
+    return static_cast<int>((unique_nack_requests * 100.0f / nack_requests) +
+                            0.5f);
+  }
+
+  uint32_t nack_packets;          // Number of RTCP NACK packets.
+  uint32_t fir_packets;           // Number of RTCP FIR packets.
+  uint32_t pli_packets;           // Number of RTCP PLI packets.
+  uint32_t nack_requests;         // Number of NACKed RTP packets.
+  uint32_t unique_nack_requests;  // Number of unique NACKed RTP packets.
+};
+
+class RtcpPacketTypeCounterObserver {
+ public:
+  virtual ~RtcpPacketTypeCounterObserver() {}
+  virtual void RtcpPacketTypesCounterUpdated(
+      uint32_t ssrc,
+      const RtcpPacketTypeCounter& packet_counter) = 0;
+};
+
+// Invoked for each cname passed in RTCP SDES blocks.
+class RtcpCnameCallback {
+ public:
+  virtual ~RtcpCnameCallback() = default;
+
+  virtual void OnCname(uint32_t ssrc, absl::string_view cname) = 0;
+};
+
+}  // namespace webrtc
+#endif  // MODULES_RTP_RTCP_INCLUDE_RTCP_STATISTICS_H_
diff --git a/third_party/libwebrtc/modules/rtp_rtcp/include/rtp_cvo.h b/third_party/libwebrtc/modules/rtp_rtcp/include/rtp_cvo.h
new file mode 100644
index 0000000000..497946d6a7
--- /dev/null
+++ b/third_party/libwebrtc/modules/rtp_rtcp/include/rtp_cvo.h
@@ -0,0 +1,56 @@
+/*
+ *  Copyright (c) 2015 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_RTP_RTCP_INCLUDE_RTP_CVO_H_
+#define MODULES_RTP_RTCP_INCLUDE_RTP_CVO_H_
+
+#include "api/video/video_rotation.h"
+#include "rtc_base/checks.h"
+
+namespace webrtc {
+
+// Please refer to http://www.etsi.org/deliver/etsi_ts/126100_126199/126114/
+// 12.07.00_60/ts_126114v120700p.pdf Section 7.4.5. The rotation of a frame is
+// the clockwise angle the frames must be rotated in order to display the frames
+// correctly if the display is rotated in its natural orientation.
+inline uint8_t ConvertVideoRotationToCVOByte(VideoRotation rotation) {
+  switch (rotation) {
+    case kVideoRotation_0:
+      return 0;
+    case kVideoRotation_90:
+      return 1;
+    case kVideoRotation_180:
+      return 2;
+    case kVideoRotation_270:
+      return 3;
+  }
+  RTC_DCHECK_NOTREACHED();
+  return 0;
+}
+
+inline VideoRotation ConvertCVOByteToVideoRotation(uint8_t cvo_byte) {
+  // CVO byte: |0 0 0 0 C F R R|.
+  const uint8_t rotation_bits = cvo_byte & 0x3;
+  switch (rotation_bits) {
+    case 0:
+      return kVideoRotation_0;
+    case 1:
+      return kVideoRotation_90;
+    case 2:
+      return kVideoRotation_180;
+    case 3:
+      return kVideoRotation_270;
+    default:
+      RTC_DCHECK_NOTREACHED();
+      return kVideoRotation_0;
+  }
+}
+
+}  // namespace webrtc
+#endif  // MODULES_RTP_RTCP_INCLUDE_RTP_CVO_H_
diff --git a/third_party/libwebrtc/modules/rtp_rtcp/include/rtp_header_extension_map.h b/third_party/libwebrtc/modules/rtp_rtcp/include/rtp_header_extension_map.h
new file mode 100644
index 0000000000..ff1ea61f52
--- /dev/null
+++ b/third_party/libwebrtc/modules/rtp_rtcp/include/rtp_header_extension_map.h
@@ -0,0 +1,75 @@
+/*
+ *  Copyright (c) 2012 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_RTP_RTCP_INCLUDE_RTP_HEADER_EXTENSION_MAP_H_
+#define MODULES_RTP_RTCP_INCLUDE_RTP_HEADER_EXTENSION_MAP_H_
+
+#include <stdint.h>
+
+#include <string>
+
+#include "absl/strings/string_view.h"
+#include "api/array_view.h"
+#include "api/rtp_parameters.h"
+#include "modules/rtp_rtcp/include/rtp_rtcp_defines.h"
+#include "rtc_base/checks.h"
+
+namespace webrtc {
+
+class RtpHeaderExtensionMap {
+ public:
+  static constexpr RTPExtensionType kInvalidType = kRtpExtensionNone;
+  static constexpr int kInvalidId = 0;
+
+  RtpHeaderExtensionMap();
+  explicit RtpHeaderExtensionMap(bool extmap_allow_mixed);
+  explicit RtpHeaderExtensionMap(rtc::ArrayView<const RtpExtension> extensions);
+
+  void Reset(rtc::ArrayView<const RtpExtension> extensions);
+
+  template <typename Extension>
+  bool Register(int id) {
+    return Register(id, Extension::kId, Extension::Uri());
+  }
+  bool RegisterByType(int id, RTPExtensionType type);
+  bool RegisterByUri(int id, absl::string_view uri);
+
+  bool IsRegistered(RTPExtensionType type) const {
+    return GetId(type) != kInvalidId;
+  }
+  // Return kInvalidType if not found.
+  RTPExtensionType GetType(int id) const;
+  // Return kInvalidId if not found.
+  uint8_t GetId(RTPExtensionType type) const {
+    RTC_DCHECK_GT(type, kRtpExtensionNone);
+    RTC_DCHECK_LT(type, kRtpExtensionNumberOfExtensions);
+    return ids_[type];
+  }
+
+  void Deregister(absl::string_view uri);
+
+  // Corresponds to the SDP attribute extmap-allow-mixed, see RFC8285.
+  // Set to true if it's allowed to mix one- and two-byte RTP header extensions
+  // in the same stream.
+  bool ExtmapAllowMixed() const { return extmap_allow_mixed_; }
+  void SetExtmapAllowMixed(bool extmap_allow_mixed) {
+    extmap_allow_mixed_ = extmap_allow_mixed;
+  }
+
+ private:
+  bool Register(int id, RTPExtensionType type, absl::string_view uri);
+
+  uint8_t ids_[kRtpExtensionNumberOfExtensions];
+  bool extmap_allow_mixed_;
+};
+
+}  // namespace webrtc
+
+#endif  // MODULES_RTP_RTCP_INCLUDE_RTP_HEADER_EXTENSION_MAP_H_
diff --git a/third_party/libwebrtc/modules/rtp_rtcp/include/rtp_packet_sender.h b/third_party/libwebrtc/modules/rtp_rtcp/include/rtp_packet_sender.h
new file mode 100644
index 0000000000..ebc65298a5
--- /dev/null
+++ b/third_party/libwebrtc/modules/rtp_rtcp/include/rtp_packet_sender.h
@@ -0,0 +1,40 @@
+/*
+ *  Copyright (c) 2019 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_RTP_RTCP_INCLUDE_RTP_PACKET_SENDER_H_
+#define MODULES_RTP_RTCP_INCLUDE_RTP_PACKET_SENDER_H_
+
+#include <memory>
+#include <vector>
+
+#include "modules/rtp_rtcp/include/rtp_rtcp_defines.h"
+#include "modules/rtp_rtcp/source/rtp_packet_to_send.h"
+
+namespace webrtc {
+
+class RtpPacketSender {
+ public:
+  virtual ~RtpPacketSender() = default;
+
+  // Insert a set of packets into queue, for eventual transmission. Based on the
+  // type of packets, they will be prioritized and scheduled relative to other
+  // packets and the current target send rate.
+  virtual void EnqueuePackets(
+      std::vector<std::unique_ptr<RtpPacketToSend>> packets) = 0;
+
+  // Clear any pending packets with the given SSRC from the queue.
+  // TODO(crbug.com/1395081): Make pure virtual when downstream code has been
+  // updated.
+  virtual void RemovePacketsForSsrc(uint32_t ssrc) {}
+};
+
+}  // namespace webrtc
+
+#endif  // MODULES_RTP_RTCP_INCLUDE_RTP_PACKET_SENDER_H_
diff --git a/third_party/libwebrtc/modules/rtp_rtcp/include/rtp_rtcp.h b/third_party/libwebrtc/modules/rtp_rtcp/include/rtp_rtcp.h
new file mode 100644
index 0000000000..e56d5ef637
--- /dev/null
+++ b/third_party/libwebrtc/modules/rtp_rtcp/include/rtp_rtcp.h
@@ -0,0 +1,38 @@
+/*
+ *  Copyright (c) 2012 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_RTP_RTCP_INCLUDE_RTP_RTCP_H_
+#define MODULES_RTP_RTCP_INCLUDE_RTP_RTCP_H_
+
+#include <memory>
+
+#include "absl/base/attributes.h"
+#include "modules/rtp_rtcp/source/rtp_rtcp_interface.h"
+
+namespace webrtc {
+
+class ABSL_DEPRECATED("") RtpRtcp : public RtpRtcpInterface {
+ public:
+  // Instantiates a deprecated version of the RtpRtcp module.
+  static std::unique_ptr<RtpRtcp> ABSL_DEPRECATED("")
+      Create(const Configuration& configuration) {
+    return DEPRECATED_Create(configuration);
+  }
+
+  static std::unique_ptr<RtpRtcp> DEPRECATED_Create(
+      const Configuration& configuration);
+
+  // Process any pending tasks such as timeouts.
+  virtual void Process() = 0;
+};
+
+}  // namespace webrtc
+
+#endif  // MODULES_RTP_RTCP_INCLUDE_RTP_RTCP_H_
diff --git a/third_party/libwebrtc/modules/rtp_rtcp/include/rtp_rtcp_defines.cc b/third_party/libwebrtc/modules/rtp_rtcp/include/rtp_rtcp_defines.cc
new file mode 100644
index 0000000000..0d91ab9546
--- /dev/null
+++ b/third_party/libwebrtc/modules/rtp_rtcp/include/rtp_rtcp_defines.cc
@@ -0,0 +1,75 @@
+/*
+ *  Copyright (c) 2017 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/rtp_rtcp_defines.h"
+
+#include <string.h>
+
+#include <type_traits>
+
+#include "absl/algorithm/container.h"
+#include "api/array_view.h"
+#include "modules/rtp_rtcp/source/rtp_packet.h"
+#include "modules/rtp_rtcp/source/rtp_packet_to_send.h"
+
+namespace webrtc {
+
+namespace {
+constexpr size_t kMidRsidMaxSize = 16;
+
+// Check if passed character is a "token-char" from RFC 4566.
+// https://datatracker.ietf.org/doc/html/rfc4566#section-9
+//    token-char =          %x21 / %x23-27 / %x2A-2B / %x2D-2E / %x30-39
+//                         / %x41-5A / %x5E-7E
+bool IsTokenChar(char ch) {
+  return ch == 0x21 || (ch >= 0x23 && ch <= 0x27) || ch == 0x2a || ch == 0x2b ||
+         ch == 0x2d || ch == 0x2e || (ch >= 0x30 && ch <= 0x39) ||
+         (ch >= 0x41 && ch <= 0x5a) || (ch >= 0x5e && ch <= 0x7e);
+}
+}  // namespace
+
+bool IsLegalMidName(absl::string_view name) {
+  return (name.size() <= kMidRsidMaxSize && !name.empty() &&
+          absl::c_all_of(name, IsTokenChar));
+}
+
+bool IsLegalRsidName(absl::string_view name) {
+  return (name.size() <= kMidRsidMaxSize && !name.empty() &&
+          absl::c_all_of(name, isalnum));
+}
+
+StreamDataCounters::StreamDataCounters() = default;
+
+RtpPacketCounter::RtpPacketCounter(const RtpPacket& packet)
+    : header_bytes(packet.headers_size()),
+      payload_bytes(packet.payload_size()),
+      padding_bytes(packet.padding_size()),
+      packets(1) {}
+
+RtpPacketCounter::RtpPacketCounter(const RtpPacketToSend& packet_to_send)
+    : RtpPacketCounter(static_cast<const RtpPacket&>(packet_to_send)) {
+  total_packet_delay =
+      packet_to_send.time_in_send_queue().value_or(TimeDelta::Zero());
+}
+
+void RtpPacketCounter::AddPacket(const RtpPacket& packet) {
+  ++packets;
+  header_bytes += packet.headers_size();
+  padding_bytes += packet.padding_size();
+  payload_bytes += packet.payload_size();
+}
+
+void RtpPacketCounter::AddPacket(const RtpPacketToSend& packet_to_send) {
+  AddPacket(static_cast<const RtpPacket&>(packet_to_send));
+  total_packet_delay +=
+      packet_to_send.time_in_send_queue().value_or(TimeDelta::Zero());
+}
+
+}  // namespace webrtc
diff --git a/third_party/libwebrtc/modules/rtp_rtcp/include/rtp_rtcp_defines.h b/third_party/libwebrtc/modules/rtp_rtcp/include/rtp_rtcp_defines.h
new file mode 100644
index 0000000000..de85abd4ae
--- /dev/null
+++ b/third_party/libwebrtc/modules/rtp_rtcp/include/rtp_rtcp_defines.h
@@ -0,0 +1,428 @@
+/*
+ *  Copyright (c) 2012 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_RTP_RTCP_INCLUDE_RTP_RTCP_DEFINES_H_
+#define MODULES_RTP_RTCP_INCLUDE_RTP_RTCP_DEFINES_H_
+
+#include <stddef.h>
+
+#include <memory>
+#include <vector>
+
+#include "absl/algorithm/container.h"
+#include "absl/strings/string_view.h"
+#include "absl/types/optional.h"
+#include "absl/types/variant.h"
+#include "api/array_view.h"
+#include "api/audio_codecs/audio_format.h"
+#include "api/rtp_headers.h"
+#include "api/transport/network_types.h"
+#include "api/units/data_rate.h"
+#include "api/units/time_delta.h"
+#include "api/units/timestamp.h"
+#include "modules/rtp_rtcp/include/report_block_data.h"
+#include "modules/rtp_rtcp/source/rtcp_packet/remote_estimate.h"
+#include "system_wrappers/include/clock.h"
+
+#define RTCP_CNAME_SIZE 256  // RFC 3550 page 44, including null termination
+#define IP_PACKET_SIZE 1500  // we assume ethernet
+
+namespace webrtc {
+class RtpPacket;
+class RtpPacketToSend;
+namespace rtcp {
+class TransportFeedback;
+}
+
+const int kVideoPayloadTypeFrequency = 90000;
+
+// TODO(bugs.webrtc.org/6458): Remove this when all the depending projects are
+// updated to correctly set rtp rate for RtcpSender.
+const int kBogusRtpRateForAudioRtcp = 8000;
+
+// Minimum RTP header size in bytes.
+const uint8_t kRtpHeaderSize = 12;
+
+bool IsLegalMidName(absl::string_view name);
+bool IsLegalRsidName(absl::string_view name);
+
+// This enum must not have any gaps, i.e., all integers between
+// kRtpExtensionNone and kRtpExtensionNumberOfExtensions must be valid enum
+// entries.
+enum RTPExtensionType : int {
+  kRtpExtensionNone,
+  kRtpExtensionTransmissionTimeOffset,
+  kRtpExtensionAudioLevel,
+  kRtpExtensionCsrcAudioLevel,
+  kRtpExtensionInbandComfortNoise,
+  kRtpExtensionAbsoluteSendTime,
+  kRtpExtensionAbsoluteCaptureTime,
+  kRtpExtensionVideoRotation,
+  kRtpExtensionTransportSequenceNumber,
+  kRtpExtensionTransportSequenceNumber02,
+  kRtpExtensionPlayoutDelay,
+  kRtpExtensionVideoContentType,
+  kRtpExtensionVideoLayersAllocation,
+  kRtpExtensionVideoTiming,
+  kRtpExtensionRtpStreamId,
+  kRtpExtensionRepairedRtpStreamId,
+  kRtpExtensionMid,
+  kRtpExtensionGenericFrameDescriptor,
+  kRtpExtensionGenericFrameDescriptor00 [[deprecated]] =
+      kRtpExtensionGenericFrameDescriptor,
+  kRtpExtensionDependencyDescriptor,
+  kRtpExtensionGenericFrameDescriptor02 [[deprecated]] =
+      kRtpExtensionDependencyDescriptor,
+  kRtpExtensionColorSpace,
+  kRtpExtensionVideoFrameTrackingId,
+  kRtpExtensionNumberOfExtensions  // Must be the last entity in the enum.
+};
+
+enum RTCPAppSubTypes { kAppSubtypeBwe = 0x00 };
+
+// TODO(sprang): Make this an enum class once rtcp_receiver has been cleaned up.
+enum RTCPPacketType : uint32_t {
+  kRtcpReport = 0x0001,
+  kRtcpSr = 0x0002,
+  kRtcpRr = 0x0004,
+  kRtcpSdes = 0x0008,
+  kRtcpBye = 0x0010,
+  kRtcpPli = 0x0020,
+  kRtcpNack = 0x0040,
+  kRtcpFir = 0x0080,
+  kRtcpTmmbr = 0x0100,
+  kRtcpTmmbn = 0x0200,
+  kRtcpSrReq = 0x0400,
+  kRtcpLossNotification = 0x2000,
+  kRtcpRemb = 0x10000,
+  kRtcpTransmissionTimeOffset = 0x20000,
+  kRtcpXrReceiverReferenceTime = 0x40000,
+  kRtcpXrDlrrReportBlock = 0x80000,
+  kRtcpTransportFeedback = 0x100000,
+  kRtcpXrTargetBitrate = 0x200000
+};
+
+enum class KeyFrameReqMethod : uint8_t {
+  kNone,     // Don't request keyframes.
+  kPliRtcp,  // Request keyframes through Picture Loss Indication.
+  kFirRtcp   // Request keyframes through Full Intra-frame Request.
+};
+
+enum RtxMode {
+  kRtxOff = 0x0,
+  kRtxRetransmitted = 0x1,     // Only send retransmissions over RTX.
+  kRtxRedundantPayloads = 0x2  // Preventively send redundant payloads
+                               // instead of padding.
+};
+
+const size_t kRtxHeaderSize = 2;
+
+struct RtpState {
+  uint16_t sequence_number = 0;
+  uint32_t start_timestamp = 0;
+  uint32_t timestamp = 0;
+  Timestamp capture_time = Timestamp::MinusInfinity();
+  Timestamp last_timestamp_time = Timestamp::MinusInfinity();
+  bool ssrc_has_acked = false;
+};
+
+class RtcpIntraFrameObserver {
+ public:
+  virtual ~RtcpIntraFrameObserver() {}
+
+  virtual void OnReceivedIntraFrameRequest(uint32_t ssrc) = 0;
+};
+
+// Observer for incoming LossNotification RTCP messages.
+// See the documentation of LossNotification for details.
+class RtcpLossNotificationObserver {
+ public:
+  virtual ~RtcpLossNotificationObserver() = default;
+
+  virtual void OnReceivedLossNotification(uint32_t ssrc,
+                                          uint16_t seq_num_of_last_decodable,
+                                          uint16_t seq_num_of_last_received,
+                                          bool decodability_flag) = 0;
+};
+
+// Interface to watch incoming rtcp packets related to the link in general.
+// All message handlers have default empty implementation. This way users only
+// need to implement the ones they are interested in.
+// All message handles pass `receive_time` parameter, which is receive time
+// of the rtcp packet that triggered the update.
+class NetworkLinkRtcpObserver {
+ public:
+  virtual ~NetworkLinkRtcpObserver() = default;
+
+  virtual void OnTransportFeedback(Timestamp receive_time,
+                                   const rtcp::TransportFeedback& feedback) {}
+  virtual void OnReceiverEstimatedMaxBitrate(Timestamp receive_time,
+                                             DataRate bitrate) {}
+
+  // Called on an RTCP packet with sender or receiver reports with non zero
+  // report blocks. Report blocks are combined from all reports into one array.
+  virtual void OnReport(Timestamp receive_time,
+                        rtc::ArrayView<const ReportBlockData> report_blocks) {}
+  virtual void OnRttUpdate(Timestamp receive_time, TimeDelta rtt) {}
+};
+
+class RtcpEventObserver {
+ public:
+  virtual void OnRtcpBye() = 0;
+  virtual void OnRtcpTimeout() = 0;
+
+  virtual ~RtcpEventObserver() {}
+};
+
+// NOTE! `kNumMediaTypes` must be kept in sync with RtpPacketMediaType!
+static constexpr size_t kNumMediaTypes = 5;
+enum class RtpPacketMediaType : size_t {
+  kAudio,                         // Audio media packets.
+  kVideo,                         // Video media packets.
+  kRetransmission,                // Retransmisions, sent as response to NACK.
+  kForwardErrorCorrection,        // FEC packets.
+  kPadding = kNumMediaTypes - 1,  // RTX or plain padding sent to maintain BWE.
+  // Again, don't forget to update `kNumMediaTypes` if you add another value!
+};
+
+struct RtpPacketSendInfo {
+  uint16_t transport_sequence_number = 0;
+  absl::optional<uint32_t> media_ssrc;
+  uint16_t rtp_sequence_number = 0;  // Only valid if `media_ssrc` is set.
+  uint32_t rtp_timestamp = 0;
+  size_t length = 0;
+  absl::optional<RtpPacketMediaType> packet_type;
+  PacedPacketInfo pacing_info;
+};
+
+class NetworkStateEstimateObserver {
+ public:
+  virtual void OnRemoteNetworkEstimate(NetworkStateEstimate estimate) = 0;
+  virtual ~NetworkStateEstimateObserver() = default;
+};
+
+class TransportFeedbackObserver {
+ public:
+  virtual ~TransportFeedbackObserver() = default;
+
+  virtual void OnAddPacket(const RtpPacketSendInfo& packet_info) = 0;
+};
+
+// Interface for PacketRouter to send rtcp feedback on behalf of
+// congestion controller.
+// TODO(bugs.webrtc.org/8239): Remove and use RtcpTransceiver directly
+// when RtcpTransceiver always present in rtp transport.
+class RtcpFeedbackSenderInterface {
+ public:
+  virtual ~RtcpFeedbackSenderInterface() = default;
+  virtual void SendCombinedRtcpPacket(
+      std::vector<std::unique_ptr<rtcp::RtcpPacket>> rtcp_packets) = 0;
+  virtual void SetRemb(int64_t bitrate_bps, std::vector<uint32_t> ssrcs) = 0;
+  virtual void UnsetRemb() = 0;
+};
+
+class StreamFeedbackObserver {
+ public:
+  struct StreamPacketInfo {
+    bool received;
+
+    // `rtp_sequence_number` and `is_retransmission` are only valid if `ssrc`
+    // is populated.
+    absl::optional<uint32_t> ssrc;
+    uint16_t rtp_sequence_number;
+    bool is_retransmission;
+  };
+  virtual ~StreamFeedbackObserver() = default;
+
+  virtual void OnPacketFeedbackVector(
+      std::vector<StreamPacketInfo> packet_feedback_vector) = 0;
+};
+
+class StreamFeedbackProvider {
+ public:
+  virtual void RegisterStreamFeedbackObserver(
+      std::vector<uint32_t> ssrcs,
+      StreamFeedbackObserver* observer) = 0;
+  virtual void DeRegisterStreamFeedbackObserver(
+      StreamFeedbackObserver* observer) = 0;
+  virtual ~StreamFeedbackProvider() = default;
+};
+
+class RtcpRttStats {
+ public:
+  virtual void OnRttUpdate(int64_t rtt) = 0;
+
+  virtual int64_t LastProcessedRtt() const = 0;
+
+  virtual ~RtcpRttStats() {}
+};
+
+struct RtpPacketCounter {
+  RtpPacketCounter()
+      : header_bytes(0), payload_bytes(0), padding_bytes(0), packets(0) {}
+
+  explicit RtpPacketCounter(const RtpPacket& packet);
+  explicit RtpPacketCounter(const RtpPacketToSend& packet_to_send);
+
+  void Add(const RtpPacketCounter& other) {
+    header_bytes += other.header_bytes;
+    payload_bytes += other.payload_bytes;
+    padding_bytes += other.padding_bytes;
+    packets += other.packets;
+    total_packet_delay += other.total_packet_delay;
+  }
+
+  bool operator==(const RtpPacketCounter& other) const {
+    return header_bytes == other.header_bytes &&
+           payload_bytes == other.payload_bytes &&
+           padding_bytes == other.padding_bytes && packets == other.packets &&
+           total_packet_delay == other.total_packet_delay;
+  }
+
+  // Not inlined, since use of RtpPacket would result in circular includes.
+  void AddPacket(const RtpPacket& packet);
+  void AddPacket(const RtpPacketToSend& packet_to_send);
+
+  size_t TotalBytes() const {
+    return header_bytes + payload_bytes + padding_bytes;
+  }
+
+  size_t header_bytes;   // Number of bytes used by RTP headers.
+  size_t payload_bytes;  // Payload bytes, excluding RTP headers and padding.
+  size_t padding_bytes;  // Number of padding bytes.
+  size_t packets;        // Number of packets.
+  // The total delay of all `packets`. For RtpPacketToSend packets, this is
+  // `time_in_send_queue()`. For receive packets, this is zero.
+  webrtc::TimeDelta total_packet_delay = webrtc::TimeDelta::Zero();
+};
+
+// Data usage statistics for a (rtp) stream.
+struct StreamDataCounters {
+  StreamDataCounters();
+
+  void Add(const StreamDataCounters& other) {
+    transmitted.Add(other.transmitted);
+    retransmitted.Add(other.retransmitted);
+    fec.Add(other.fec);
+    if (other.first_packet_time < first_packet_time) {
+      // Use oldest time (excluding unsed value represented as plus infinity.
+      first_packet_time = other.first_packet_time;
+    }
+  }
+
+  void MaybeSetFirstPacketTime(Timestamp now) {
+    if (first_packet_time == Timestamp::PlusInfinity()) {
+      first_packet_time = now;
+    }
+  }
+
+  // Return time since first packet is send/received, or zero if such event
+  // haven't happen.
+  TimeDelta TimeSinceFirstPacket(Timestamp now) const {
+    return first_packet_time == Timestamp::PlusInfinity()
+               ? TimeDelta::Zero()
+               : now - first_packet_time;
+  }
+
+  // Returns the number of bytes corresponding to the actual media payload (i.e.
+  // RTP headers, padding, retransmissions and fec packets are excluded).
+  // Note this function does not have meaning for an RTX stream.
+  size_t MediaPayloadBytes() const {
+    return transmitted.payload_bytes - retransmitted.payload_bytes -
+           fec.payload_bytes;
+  }
+
+  // Time when first packet is sent/received.
+  Timestamp first_packet_time = Timestamp::PlusInfinity();
+
+  RtpPacketCounter transmitted;    // Number of transmitted packets/bytes.
+  RtpPacketCounter retransmitted;  // Number of retransmitted packets/bytes.
+  RtpPacketCounter fec;            // Number of redundancy packets/bytes.
+};
+
+class RtpSendRates {
+  template <std::size_t... Is>
+  constexpr std::array<DataRate, sizeof...(Is)> make_zero_array(
+      std::index_sequence<Is...>) {
+    return {{(static_cast<void>(Is), DataRate::Zero())...}};
+  }
+
+ public:
+  RtpSendRates()
+      : send_rates_(
+            make_zero_array(std::make_index_sequence<kNumMediaTypes>())) {}
+  RtpSendRates(const RtpSendRates& rhs) = default;
+  RtpSendRates& operator=(const RtpSendRates&) = default;
+
+  DataRate& operator[](RtpPacketMediaType type) {
+    return send_rates_[static_cast<size_t>(type)];
+  }
+  const DataRate& operator[](RtpPacketMediaType type) const {
+    return send_rates_[static_cast<size_t>(type)];
+  }
+  DataRate Sum() const {
+    return absl::c_accumulate(send_rates_, DataRate::Zero());
+  }
+
+ private:
+  std::array<DataRate, kNumMediaTypes> send_rates_;
+};
+
+// Callback, called whenever byte/packet counts have been updated.
+class StreamDataCountersCallback {
+ public:
+  virtual ~StreamDataCountersCallback() {}
+
+  virtual void DataCountersUpdated(const StreamDataCounters& counters,
+                                   uint32_t ssrc) = 0;
+};
+
+// Information exposed through the GetStats api.
+struct RtpReceiveStats {
+  // `packets_lost` and `jitter` are defined by RFC 3550, and exposed in the
+  // RTCReceivedRtpStreamStats dictionary, see
+  // https://w3c.github.io/webrtc-stats/#receivedrtpstats-dict*
+  int32_t packets_lost = 0;
+  // Interarrival jitter in samples.
+  uint32_t jitter = 0;
+  // Interarrival jitter in time.
+  webrtc::TimeDelta interarrival_jitter = webrtc::TimeDelta::Zero();
+
+  // Time of the last packet received in unix epoch,
+  // i.e. Timestamp::Zero() represents 1st Jan 1970 00:00
+  absl::optional<Timestamp> last_packet_received;
+
+  // Counters exposed in RTCInboundRtpStreamStats, see
+  // https://w3c.github.io/webrtc-stats/#inboundrtpstats-dict*
+  RtpPacketCounter packet_counter;
+};
+
+// Callback, used to notify an observer whenever new rates have been estimated.
+class BitrateStatisticsObserver {
+ public:
+  virtual ~BitrateStatisticsObserver() {}
+
+  virtual void Notify(uint32_t total_bitrate_bps,
+                      uint32_t retransmit_bitrate_bps,
+                      uint32_t ssrc) = 0;
+};
+
+// Callback, used to notify an observer whenever a packet is sent to the
+// transport.
+class SendPacketObserver {
+ public:
+  virtual ~SendPacketObserver() = default;
+  virtual void OnSendPacket(absl::optional<uint16_t> packet_id,
+                            Timestamp capture_time,
+                            uint32_t ssrc) = 0;
+};
+
+}  // namespace webrtc
+#endif  // MODULES_RTP_RTCP_INCLUDE_RTP_RTCP_DEFINES_H_