1 /*
2  *  Copyright (c) 2018 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 API_TEST_NETEQ_SIMULATOR_H_
12 #define API_TEST_NETEQ_SIMULATOR_H_
13 
14 #include <stdint.h>
15 
16 #include <map>
17 #include <vector>
18 
19 namespace webrtc {
20 namespace test {
21 
22 class NetEqSimulator {
23  public:
24   virtual ~NetEqSimulator() = default;
25 
26   enum class Action { kNormal, kExpand, kAccelerate, kPreemptiveExpand };
27 
28   // The results of one simulation step.
29   struct SimulationStepResult {
30     SimulationStepResult();
31     SimulationStepResult(const SimulationStepResult& other);
32     ~SimulationStepResult();
33 
34     bool is_simulation_finished = false;
35     // The amount of audio produced (in ms) with the actions in this time step.
36     std::map<Action, int> action_times_ms;
37     // The amount of wall clock time (in ms) that elapsed since the previous
38     // event. This is not necessarily equal to the sum of the values in
39     // action_times_ms.
40     int64_t simulation_step_ms = 0;
41   };
42 
43   struct NetEqState {
44     NetEqState();
45     NetEqState(const NetEqState& other);
46     ~NetEqState();
47     // The sum of the packet buffer and sync buffer delay.
48     int current_delay_ms = 0;
49     // An indicator that packet loss occurred since the last GetAudio event.
50     bool packet_loss_occurred = false;
51     // An indicator that the packet buffer has been flushed since the last
52     // GetAudio event.
53     bool packet_buffer_flushed = false;
54     // Indicates if the next needed packet is available in the buffer.
55     bool next_packet_available = false;
56     // The inter-arrival times in ms of the packets that have arrived since the
57     // last GetAudio event.
58     std::vector<int> packet_iat_ms;
59     // The current packet size in ms.
60     int packet_size_ms = 0;
61   };
62 
63   // Runs the simulation until the end. Returns the duration of the produced
64   // audio in ms.
65   virtual int64_t Run() = 0;
66   // Runs the simulation until we hit the next GetAudio event. If the simulation
67   // is finished, is_simulation_finished will be set to true in the returned
68   // SimulationStepResult.
69   virtual SimulationStepResult RunToNextGetAudio() = 0;
70 
71   // Set the next action to be taken by NetEq. This will override any action
72   // that NetEq would normally decide to take.
73   virtual void SetNextAction(Action next_operation) = 0;
74 
75   // Get the current state of NetEq.
76   virtual NetEqState GetNetEqState() = 0;
77 };
78 
79 }  // namespace test
80 }  // namespace webrtc
81 
82 #endif  // API_TEST_NETEQ_SIMULATOR_H_
83