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 #include "modules/audio_coding/neteq/delay_manager.h"
12
13 #include <stdio.h>
14 #include <stdlib.h>
15
16 #include <algorithm>
17 #include <memory>
18 #include <numeric>
19 #include <string>
20
21 #include "modules/include/module_common_types_public.h"
22 #include "rtc_base/checks.h"
23 #include "rtc_base/experiments/struct_parameters_parser.h"
24 #include "rtc_base/logging.h"
25 #include "rtc_base/numerics/safe_conversions.h"
26 #include "rtc_base/numerics/safe_minmax.h"
27 #include "system_wrappers/include/field_trial.h"
28
29 namespace webrtc {
30 namespace {
31
32 constexpr int kMinBaseMinimumDelayMs = 0;
33 constexpr int kMaxBaseMinimumDelayMs = 10000;
34 constexpr int kStartDelayMs = 80;
35
MaybeCreateReorderOptimizer(const DelayManager::Config & config)36 std::unique_ptr<ReorderOptimizer> MaybeCreateReorderOptimizer(
37 const DelayManager::Config& config) {
38 if (!config.use_reorder_optimizer) {
39 return nullptr;
40 }
41 return std::make_unique<ReorderOptimizer>(
42 (1 << 15) * config.reorder_forget_factor, config.ms_per_loss_percent,
43 config.start_forget_weight);
44 }
45
46 } // namespace
47
Config()48 DelayManager::Config::Config() {
49 StructParametersParser::Create( //
50 "quantile", &quantile, //
51 "forget_factor", &forget_factor, //
52 "start_forget_weight", &start_forget_weight, //
53 "resample_interval_ms", &resample_interval_ms, //
54 "use_reorder_optimizer", &use_reorder_optimizer, //
55 "reorder_forget_factor", &reorder_forget_factor, //
56 "ms_per_loss_percent", &ms_per_loss_percent)
57 ->Parse(webrtc::field_trial::FindFullName(
58 "WebRTC-Audio-NetEqDelayManagerConfig"));
59 }
60
Log()61 void DelayManager::Config::Log() {
62 RTC_LOG(LS_INFO) << "Delay manager config:"
63 " quantile="
64 << quantile << " forget_factor=" << forget_factor
65 << " start_forget_weight=" << start_forget_weight.value_or(0)
66 << " resample_interval_ms="
67 << resample_interval_ms.value_or(0)
68 << " use_reorder_optimizer=" << use_reorder_optimizer
69 << " reorder_forget_factor=" << reorder_forget_factor
70 << " ms_per_loss_percent=" << ms_per_loss_percent;
71 }
72
DelayManager(const Config & config,const TickTimer * tick_timer)73 DelayManager::DelayManager(const Config& config, const TickTimer* tick_timer)
74 : max_packets_in_buffer_(config.max_packets_in_buffer),
75 underrun_optimizer_(tick_timer,
76 (1 << 30) * config.quantile,
77 (1 << 15) * config.forget_factor,
78 config.start_forget_weight,
79 config.resample_interval_ms),
80 reorder_optimizer_(MaybeCreateReorderOptimizer(config)),
81 base_minimum_delay_ms_(config.base_minimum_delay_ms),
82 effective_minimum_delay_ms_(config.base_minimum_delay_ms),
83 minimum_delay_ms_(0),
84 maximum_delay_ms_(0),
85 target_level_ms_(kStartDelayMs) {
86 RTC_DCHECK_GE(base_minimum_delay_ms_, 0);
87
88 Reset();
89 }
90
~DelayManager()91 DelayManager::~DelayManager() {}
92
Update(int arrival_delay_ms,bool reordered)93 void DelayManager::Update(int arrival_delay_ms, bool reordered) {
94 if (!reorder_optimizer_ || !reordered) {
95 underrun_optimizer_.Update(arrival_delay_ms);
96 }
97 target_level_ms_ =
98 underrun_optimizer_.GetOptimalDelayMs().value_or(kStartDelayMs);
99 if (reorder_optimizer_) {
100 reorder_optimizer_->Update(arrival_delay_ms, reordered, target_level_ms_);
101 target_level_ms_ = std::max(
102 target_level_ms_, reorder_optimizer_->GetOptimalDelayMs().value_or(0));
103 }
104 unlimited_target_level_ms_ = target_level_ms_;
105 target_level_ms_ = std::max(target_level_ms_, effective_minimum_delay_ms_);
106 if (maximum_delay_ms_ > 0) {
107 target_level_ms_ = std::min(target_level_ms_, maximum_delay_ms_);
108 }
109 if (packet_len_ms_ > 0) {
110 // Limit to 75% of maximum buffer size.
111 target_level_ms_ = std::min(
112 target_level_ms_, 3 * max_packets_in_buffer_ * packet_len_ms_ / 4);
113 }
114 }
115
SetPacketAudioLength(int length_ms)116 int DelayManager::SetPacketAudioLength(int length_ms) {
117 if (length_ms <= 0) {
118 RTC_LOG_F(LS_ERROR) << "length_ms = " << length_ms;
119 return -1;
120 }
121 packet_len_ms_ = length_ms;
122 return 0;
123 }
124
Reset()125 void DelayManager::Reset() {
126 packet_len_ms_ = 0;
127 underrun_optimizer_.Reset();
128 target_level_ms_ = kStartDelayMs;
129 if (reorder_optimizer_) {
130 reorder_optimizer_->Reset();
131 }
132 }
133
TargetDelayMs() const134 int DelayManager::TargetDelayMs() const {
135 return target_level_ms_;
136 }
137
UnlimitedTargetLevelMs() const138 int DelayManager::UnlimitedTargetLevelMs() const {
139 return unlimited_target_level_ms_;
140 }
141
IsValidMinimumDelay(int delay_ms) const142 bool DelayManager::IsValidMinimumDelay(int delay_ms) const {
143 return 0 <= delay_ms && delay_ms <= MinimumDelayUpperBound();
144 }
145
IsValidBaseMinimumDelay(int delay_ms) const146 bool DelayManager::IsValidBaseMinimumDelay(int delay_ms) const {
147 return kMinBaseMinimumDelayMs <= delay_ms &&
148 delay_ms <= kMaxBaseMinimumDelayMs;
149 }
150
SetMinimumDelay(int delay_ms)151 bool DelayManager::SetMinimumDelay(int delay_ms) {
152 if (!IsValidMinimumDelay(delay_ms)) {
153 return false;
154 }
155
156 minimum_delay_ms_ = delay_ms;
157 UpdateEffectiveMinimumDelay();
158 return true;
159 }
160
SetMaximumDelay(int delay_ms)161 bool DelayManager::SetMaximumDelay(int delay_ms) {
162 // If `delay_ms` is zero then it unsets the maximum delay and target level is
163 // unconstrained by maximum delay.
164 if (delay_ms != 0 && delay_ms < minimum_delay_ms_) {
165 // Maximum delay shouldn't be less than minimum delay or less than a packet.
166 return false;
167 }
168
169 maximum_delay_ms_ = delay_ms;
170 UpdateEffectiveMinimumDelay();
171 return true;
172 }
173
SetBaseMinimumDelay(int delay_ms)174 bool DelayManager::SetBaseMinimumDelay(int delay_ms) {
175 if (!IsValidBaseMinimumDelay(delay_ms)) {
176 return false;
177 }
178
179 base_minimum_delay_ms_ = delay_ms;
180 UpdateEffectiveMinimumDelay();
181 return true;
182 }
183
GetBaseMinimumDelay() const184 int DelayManager::GetBaseMinimumDelay() const {
185 return base_minimum_delay_ms_;
186 }
187
UpdateEffectiveMinimumDelay()188 void DelayManager::UpdateEffectiveMinimumDelay() {
189 // Clamp `base_minimum_delay_ms_` into the range which can be effectively
190 // used.
191 const int base_minimum_delay_ms =
192 rtc::SafeClamp(base_minimum_delay_ms_, 0, MinimumDelayUpperBound());
193 effective_minimum_delay_ms_ =
194 std::max(minimum_delay_ms_, base_minimum_delay_ms);
195 }
196
MinimumDelayUpperBound() const197 int DelayManager::MinimumDelayUpperBound() const {
198 // Choose the lowest possible bound discarding 0 cases which mean the value
199 // is not set and unconstrained.
200 int q75 = max_packets_in_buffer_ * packet_len_ms_ * 3 / 4;
201 q75 = q75 > 0 ? q75 : kMaxBaseMinimumDelayMs;
202 const int maximum_delay_ms =
203 maximum_delay_ms_ > 0 ? maximum_delay_ms_ : kMaxBaseMinimumDelayMs;
204 return std::min(maximum_delay_ms, q75);
205 }
206
207 } // namespace webrtc
208