Add RemoteEstimatorProxy for capturing receive times

webrtc/modules/remote_bitrate_estimator/remote_estimator_proxy.h

+/*
+ *  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 WEBRTC_MODULES_REMOTE_BITRATE_ESTIMATOR_REMOTE_ESTIMATOR_PROXY_H_
+#define WEBRTC_MODULES_REMOTE_BITRATE_ESTIMATOR_REMOTE_ESTIMATOR_PROXY_H_
+
+#include <map>
+#include <vector>
+
+#include "webrtc/base/criticalsection.h"
+#include "webrtc/modules/interface/module_common_types.h"
+#include "webrtc/modules/remote_bitrate_estimator/include/remote_bitrate_estimator.h"
+
+namespace webrtc {
+
+class Clock;
+class PacketRouter;
+namespace rtcp {
+class TransportFeedback;
+}
+
+// Class used when send-side BWE is enabled: This proxy is instantiated on the
+// receive side. It buffers a number of receive timestamps and then sends
+// transport feedback messages back too the send side.
+
+class RemoteEstimatorProxy : public RemoteBitrateEstimator {
+ public:
+  RemoteEstimatorProxy(Clock* clock, PacketRouter* packet_router);
+  virtual ~RemoteEstimatorProxy();
+
+  void IncomingPacketFeedbackVector(
+      const std::vector<PacketInfo>& packet_feedback_vector) override;
+  void IncomingPacket(int64_t arrival_time_ms,
+                      size_t payload_size,
+                      const RTPHeader& header,
+                      bool was_paced) override;
+  void RemoveStream(unsigned int ssrc) override;
+  bool LatestEstimate(std::vector<unsigned int>* ssrcs,
+                      unsigned int* bitrate_bps) const override;
+  bool GetStats(ReceiveBandwidthEstimatorStats* output) const override;
+  void OnRttUpdate(int64_t avg_rtt_ms, int64_t max_rtt_ms) override;
+  int64_t TimeUntilNextProcess() override;
+  int32_t Process() override;
+
+  static const int kDefaultProcessIntervalMs;
+  static const int kBackWindowMs;
+
+ private:
+  void OnPacketArrival(uint16_t sequence_number, int64_t arrival_time)
+      EXCLUSIVE_LOCKS_REQUIRED(&lock_);
+  bool BuildFeedbackPacket(rtcp::TransportFeedback* feedback_packetket);
+
+  Clock* const clock_;
+  PacketRouter* const packet_router_;
+  int64_t last_process_time_ms_;
+
+  rtc::CriticalSection lock_;
+
+  uint32_t media_ssrc_ GUARDED_BY(&lock_);
+  uint8_t feedback_sequence_ GUARDED_BY(&lock_);
+  SequenceNumberUnwrapper unwrapper_ GUARDED_BY(&lock_);
+  int64_t window_start_seq_ GUARDED_BY(&lock_);
+  // Map unwrapped seq -> time.
+  std::map<int64_t, int64_t> packet_arrival_times_ GUARDED_BY(&lock_);
+};
+
+}  // namespace webrtc
+
+#endif  //  WEBRTC_MODULES_REMOTE_BITRATE_ESTIMATOR_REMOTE_ESTIMATOR_PROXY_H_