1 /*
2  *  Copyright (c) 2017 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_processing/gain_controller2.h"
12 
13 #include "common_audio/include/audio_util.h"
14 #include "modules/audio_processing/audio_buffer.h"
15 #include "modules/audio_processing/include/audio_frame_view.h"
16 #include "modules/audio_processing/logging/apm_data_dumper.h"
17 #include "rtc_base/atomic_ops.h"
18 #include "rtc_base/checks.h"
19 #include "rtc_base/strings/string_builder.h"
20 
21 namespace webrtc {
22 
23 int GainController2::instance_count_ = 0;
24 
GainController2()25 GainController2::GainController2()
26     : data_dumper_(
27           new ApmDataDumper(rtc::AtomicOps::Increment(&instance_count_))),
28       gain_applier_(/*hard_clip_samples=*/false,
29                     /*initial_gain_factor=*/0.f),
30       limiter_(static_cast<size_t>(48000), data_dumper_.get(), "Agc2") {
31   if (config_.adaptive_digital.enabled) {
32     adaptive_agc_.reset(new AdaptiveAgc(data_dumper_.get()));
33   }
34 }
35 
36 GainController2::~GainController2() = default;
37 
Initialize(int sample_rate_hz)38 void GainController2::Initialize(int sample_rate_hz) {
39   RTC_DCHECK(sample_rate_hz == AudioProcessing::kSampleRate8kHz ||
40              sample_rate_hz == AudioProcessing::kSampleRate16kHz ||
41              sample_rate_hz == AudioProcessing::kSampleRate32kHz ||
42              sample_rate_hz == AudioProcessing::kSampleRate48kHz);
43   limiter_.SetSampleRate(sample_rate_hz);
44   data_dumper_->InitiateNewSetOfRecordings();
45   data_dumper_->DumpRaw("sample_rate_hz", sample_rate_hz);
46 }
47 
Process(AudioBuffer * audio)48 void GainController2::Process(AudioBuffer* audio) {
49   AudioFrameView<float> float_frame(audio->channels(), audio->num_channels(),
50                                     audio->num_frames());
51   // Apply fixed gain first, then the adaptive one.
52   gain_applier_.ApplyGain(float_frame);
53   if (adaptive_agc_) {
54     adaptive_agc_->Process(float_frame, limiter_.LastAudioLevel());
55   }
56   limiter_.Process(float_frame);
57 }
58 
NotifyAnalogLevel(int level)59 void GainController2::NotifyAnalogLevel(int level) {
60   if (analog_level_ != level && adaptive_agc_) {
61     adaptive_agc_->Reset();
62   }
63   analog_level_ = level;
64 }
65 
ApplyConfig(const AudioProcessing::Config::GainController2 & config)66 void GainController2::ApplyConfig(
67     const AudioProcessing::Config::GainController2& config) {
68   RTC_DCHECK(Validate(config))
69       << " the invalid config was " << ToString(config);
70 
71   config_ = config;
72   if (config.fixed_digital.gain_db != config_.fixed_digital.gain_db) {
73     // Reset the limiter to quickly react on abrupt level changes caused by
74     // large changes of the fixed gain.
75     limiter_.Reset();
76   }
77   gain_applier_.SetGainFactor(DbToRatio(config_.fixed_digital.gain_db));
78   if (config_.adaptive_digital.enabled) {
79     adaptive_agc_.reset(new AdaptiveAgc(data_dumper_.get(), config_));
80   } else {
81     adaptive_agc_.reset();
82   }
83 }
84 
Validate(const AudioProcessing::Config::GainController2 & config)85 bool GainController2::Validate(
86     const AudioProcessing::Config::GainController2& config) {
87   return config.fixed_digital.gain_db >= 0.f &&
88          config.fixed_digital.gain_db < 50.f &&
89          config.adaptive_digital.extra_saturation_margin_db >= 0.f &&
90          config.adaptive_digital.extra_saturation_margin_db <= 100.f;
91 }
92 
ToString(const AudioProcessing::Config::GainController2 & config)93 std::string GainController2::ToString(
94     const AudioProcessing::Config::GainController2& config) {
95   rtc::StringBuilder ss;
96   std::string adaptive_digital_level_estimator;
97   using LevelEstimatorType =
98       AudioProcessing::Config::GainController2::LevelEstimator;
99   switch (config.adaptive_digital.level_estimator) {
100     case LevelEstimatorType::kRms:
101       adaptive_digital_level_estimator = "RMS";
102       break;
103     case LevelEstimatorType::kPeak:
104       adaptive_digital_level_estimator = "peak";
105       break;
106   }
107   // clang-format off
108   // clang formatting doesn't respect custom nested style.
109   ss << "{"
110         "enabled: " << (config.enabled ? "true" : "false") << ", "
111         "fixed_digital: {gain_db: " << config.fixed_digital.gain_db << "}, "
112         "adaptive_digital: {"
113           "enabled: "
114             << (config.adaptive_digital.enabled ? "true" : "false") << ", "
115           "level_estimator: " << adaptive_digital_level_estimator << ", "
116           "extra_saturation_margin_db:"
117             << config.adaptive_digital.extra_saturation_margin_db << "}"
118           "}";
119   // clang-format on
120   return ss.Release();
121 }
122 
123 }  // namespace webrtc
124