1 /*
2  *  Copyright (c) 2015 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 #ifndef MODULES_RTP_RTCP_SOURCE_PACKET_LOSS_STATS_H_
12 #define MODULES_RTP_RTCP_SOURCE_PACKET_LOSS_STATS_H_
13 
14 #include <stdint.h>
15 
16 #include <set>
17 
18 namespace webrtc {
19 
20 // Keeps track of statistics of packet loss including whether losses are a
21 // single packet or multiple packets in a row.
22 class PacketLossStats {
23  public:
24   PacketLossStats();
25   ~PacketLossStats();
26 
27   // Adds a lost packet to the stats by sequence number.
28   void AddLostPacket(uint16_t sequence_number);
29 
30   // Queries the number of packets that were lost by themselves, no neighboring
31   // packets were lost.
32   int GetSingleLossCount() const;
33 
34   // Queries the number of times that multiple packets with sequential numbers
35   // were lost. This is the number of events with more than one packet lost,
36   // regardless of the size of the event;
37   int GetMultipleLossEventCount() const;
38 
39   // Queries the number of packets lost in multiple packet loss events. Combined
40   // with the event count, this can be used to determine the average event size.
41   int GetMultipleLossPacketCount() const;
42 
43  private:
44   std::set<uint16_t> lost_packets_buffer_;
45   std::set<uint16_t> lost_packets_wrapped_buffer_;
46   int single_loss_historic_count_;
47   int multiple_loss_historic_event_count_;
48   int multiple_loss_historic_packet_count_;
49 
50   void ComputeLossCounts(int* out_single_loss_count,
51                          int* out_multiple_loss_event_count,
52                          int* out_multiple_loss_packet_count) const;
53   void PruneBuffer();
54 };
55 
56 }  // namespace webrtc
57 
58 #endif  // MODULES_RTP_RTCP_SOURCE_PACKET_LOSS_STATS_H_
59