1 /* 2 * Copyright (c) 2012 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 // This class estimates the incoming available bandwidth. 12 13 #ifndef WEBRTC_MODULES_REMOTE_BITRATE_ESTIMATOR_INCLUDE_REMOTE_BITRATE_ESTIMATOR_H_ 14 #define WEBRTC_MODULES_REMOTE_BITRATE_ESTIMATOR_INCLUDE_REMOTE_BITRATE_ESTIMATOR_H_ 15 16 #include <map> 17 #include <vector> 18 19 #include "webrtc/common_types.h" 20 #include "webrtc/modules/interface/module.h" 21 #include "webrtc/modules/interface/module_common_types.h" 22 #include "webrtc/typedefs.h" 23 24 namespace webrtc { 25 26 class Clock; 27 28 enum RateControlType { 29 kMimdControl, 30 kAimdControl 31 }; 32 33 // RemoteBitrateObserver is used to signal changes in bitrate estimates for 34 // the incoming streams. 35 class RemoteBitrateObserver { 36 public: 37 // Called when a receive channel group has a new bitrate estimate for the 38 // incoming streams. 39 virtual void OnReceiveBitrateChanged(const std::vector<unsigned int>& ssrcs, 40 unsigned int bitrate) = 0; 41 ~RemoteBitrateObserver()42 virtual ~RemoteBitrateObserver() {} 43 }; 44 45 struct ReceiveBandwidthEstimatorStats { ReceiveBandwidthEstimatorStatsReceiveBandwidthEstimatorStats46 ReceiveBandwidthEstimatorStats() : total_propagation_time_delta_ms(0) {} 47 48 // The "propagation_time_delta" of a frame is defined as (d_arrival - d_sent), 49 // where d_arrival is the delta of the arrival times of the frame and the 50 // previous frame, d_sent is the delta of the sent times of the frame and 51 // the previous frame. The sent time is calculated from the RTP timestamp. 52 53 // |total_propagation_time_delta_ms| is the sum of the propagation_time_deltas 54 // of all received frames, except that it's is adjusted to 0 when it becomes 55 // negative. 56 int total_propagation_time_delta_ms; 57 // The propagation_time_deltas for the frames arrived in the last 58 // kProcessIntervalMs using the clock passed to 59 // RemoteBitrateEstimatorFactory::Create. 60 std::vector<int> recent_propagation_time_delta_ms; 61 // The arrival times for the frames arrived in the last kProcessIntervalMs 62 // using the clock passed to RemoteBitrateEstimatorFactory::Create. 63 std::vector<int64_t> recent_arrival_time_ms; 64 }; 65 66 struct PacketInfo { PacketInfoPacketInfo67 PacketInfo(int64_t arrival_time_ms, 68 int64_t send_time_ms, 69 uint16_t sequence_number, 70 size_t payload_size) 71 : arrival_time_ms(arrival_time_ms), 72 send_time_ms(send_time_ms), 73 sequence_number(sequence_number), 74 payload_size(payload_size) {} 75 // Time corresponding to when the packet was received. Timestamped with the 76 // receiver's clock. 77 int64_t arrival_time_ms; 78 // Time corresponding to when the packet was sent, timestamped with the 79 // sender's clock. 80 int64_t send_time_ms; 81 // Packet identifier, incremented with 1 for every packet generated by the 82 // sender. 83 uint16_t sequence_number; 84 // Size of the packet excluding RTP headers. 85 size_t payload_size; 86 }; 87 88 class RemoteBitrateEstimator : public CallStatsObserver, public Module { 89 public: ~RemoteBitrateEstimator()90 virtual ~RemoteBitrateEstimator() {} 91 IncomingPacketFeedbackVector(const std::vector<PacketInfo> & packet_feedback_vector)92 virtual void IncomingPacketFeedbackVector( 93 const std::vector<PacketInfo>& packet_feedback_vector) { 94 assert(false); 95 } 96 97 // Called for each incoming packet. Updates the incoming payload bitrate 98 // estimate and the over-use detector. If an over-use is detected the 99 // remote bitrate estimate will be updated. Note that |payload_size| is the 100 // packet size excluding headers. 101 // Note that |arrival_time_ms| can be of an arbitrary time base. 102 virtual void IncomingPacket(int64_t arrival_time_ms, 103 size_t payload_size, 104 const RTPHeader& header) = 0; 105 106 // Removes all data for |ssrc|. 107 virtual void RemoveStream(unsigned int ssrc) = 0; 108 109 // Returns true if a valid estimate exists and sets |bitrate_bps| to the 110 // estimated payload bitrate in bits per second. |ssrcs| is the list of ssrcs 111 // currently being received and of which the bitrate estimate is based upon. 112 virtual bool LatestEstimate(std::vector<unsigned int>* ssrcs, 113 unsigned int* bitrate_bps) const = 0; 114 115 // Returns true if the statistics are available. 116 virtual bool GetStats(ReceiveBandwidthEstimatorStats* output) const = 0; 117 118 protected: 119 static const int64_t kProcessIntervalMs = 1000; 120 static const int64_t kStreamTimeOutMs = 2000; 121 }; 122 123 struct RemoteBitrateEstimatorFactory { RemoteBitrateEstimatorFactoryRemoteBitrateEstimatorFactory124 RemoteBitrateEstimatorFactory() {} ~RemoteBitrateEstimatorFactoryRemoteBitrateEstimatorFactory125 virtual ~RemoteBitrateEstimatorFactory() {} 126 127 virtual RemoteBitrateEstimator* Create( 128 RemoteBitrateObserver* observer, 129 Clock* clock, 130 RateControlType control_type, 131 uint32_t min_bitrate_bps) const; 132 }; 133 134 struct AbsoluteSendTimeRemoteBitrateEstimatorFactory 135 : public RemoteBitrateEstimatorFactory { AbsoluteSendTimeRemoteBitrateEstimatorFactoryAbsoluteSendTimeRemoteBitrateEstimatorFactory136 AbsoluteSendTimeRemoteBitrateEstimatorFactory() {} ~AbsoluteSendTimeRemoteBitrateEstimatorFactoryAbsoluteSendTimeRemoteBitrateEstimatorFactory137 virtual ~AbsoluteSendTimeRemoteBitrateEstimatorFactory() {} 138 139 virtual RemoteBitrateEstimator* Create( 140 RemoteBitrateObserver* observer, 141 Clock* clock, 142 RateControlType control_type, 143 uint32_t min_bitrate_bps) const; 144 }; 145 } // namespace webrtc 146 147 #endif // WEBRTC_MODULES_REMOTE_BITRATE_ESTIMATOR_INCLUDE_REMOTE_BITRATE_ESTIMATOR_H_ 148