xref: /aosp_15_r20/external/webrtc/modules/audio_coding/audio_network_adaptor/frame_length_controller.h (revision d9f758449e529ab9291ac668be2861e7a55c2422)
1 /*
2  *  Copyright (c) 2016 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_AUDIO_CODING_AUDIO_NETWORK_ADAPTOR_FRAME_LENGTH_CONTROLLER_H_
12 #define MODULES_AUDIO_CODING_AUDIO_NETWORK_ADAPTOR_FRAME_LENGTH_CONTROLLER_H_
13 
14 #include <stddef.h>
15 
16 #include <map>
17 #include <set>
18 
19 #include "absl/types/optional.h"
20 #include "modules/audio_coding/audio_network_adaptor/controller.h"
21 #include "modules/audio_coding/audio_network_adaptor/include/audio_network_adaptor_config.h"
22 
23 namespace webrtc {
24 
25 // Determines target frame length based on the network metrics and the decision
26 // of FEC controller.
27 class FrameLengthController final : public Controller {
28  public:
29   struct Config {
30     struct FrameLengthChange {
31       FrameLengthChange(int from_frame_length_ms, int to_frame_length_ms);
32       bool operator<(const FrameLengthChange& rhs) const;
33       int from_frame_length_ms;
34       int to_frame_length_ms;
35     };
36     Config(const std::set<int>& encoder_frame_lengths_ms,
37            int initial_frame_length_ms,
38            int min_encoder_bitrate_bps,
39            float fl_increasing_packet_loss_fraction,
40            float fl_decreasing_packet_loss_fraction,
41            int fl_increase_overhead_offset,
42            int fl_decrease_overhead_offset,
43            std::map<FrameLengthChange, int> fl_changing_bandwidths_bps);
44     Config(const Config& other);
45     ~Config();
46     std::set<int> encoder_frame_lengths_ms;
47     int initial_frame_length_ms;
48     int min_encoder_bitrate_bps;
49     // Uplink packet loss fraction below which frame length can increase.
50     float fl_increasing_packet_loss_fraction;
51     // Uplink packet loss fraction below which frame length should decrease.
52     float fl_decreasing_packet_loss_fraction;
53     // Offset to apply to overhead calculation when increasing frame length.
54     int fl_increase_overhead_offset;
55     // Offset to apply to overhead calculation when decreasing frame length.
56     int fl_decrease_overhead_offset;
57     std::map<FrameLengthChange, int> fl_changing_bandwidths_bps;
58   };
59 
60   explicit FrameLengthController(const Config& config);
61 
62   ~FrameLengthController() override;
63 
64   FrameLengthController(const FrameLengthController&) = delete;
65   FrameLengthController& operator=(const FrameLengthController&) = delete;
66 
67   void UpdateNetworkMetrics(const NetworkMetrics& network_metrics) override;
68 
69   void MakeDecision(AudioEncoderRuntimeConfig* config) override;
70 
71  private:
72   bool FrameLengthIncreasingDecision(const AudioEncoderRuntimeConfig& config);
73 
74   bool FrameLengthDecreasingDecision(const AudioEncoderRuntimeConfig& config);
75 
76   const Config config_;
77 
78   std::set<int>::const_iterator frame_length_ms_;
79 
80   absl::optional<int> uplink_bandwidth_bps_;
81 
82   absl::optional<float> uplink_packet_loss_fraction_;
83 
84   absl::optional<size_t> overhead_bytes_per_packet_;
85 
86   // True if the previous frame length decision was an increase, otherwise
87   // false.
88   bool prev_decision_increase_ = false;
89 };
90 
91 }  // namespace webrtc
92 
93 #endif  // MODULES_AUDIO_CODING_AUDIO_NETWORK_ADAPTOR_FRAME_LENGTH_CONTROLLER_H_
94