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 #include "modules/audio_processing/aec3/fullband_erle_estimator.h"
12
13 #include <algorithm>
14 #include <memory>
15 #include <numeric>
16
17 #include "absl/types/optional.h"
18 #include "api/array_view.h"
19 #include "modules/audio_processing/aec3/aec3_common.h"
20 #include "modules/audio_processing/logging/apm_data_dumper.h"
21 #include "rtc_base/checks.h"
22 #include "rtc_base/numerics/safe_minmax.h"
23
24 namespace webrtc {
25
26 namespace {
27 constexpr float kEpsilon = 1e-3f;
28 constexpr float kX2BandEnergyThreshold = 44015068.0f;
29 constexpr int kBlocksToHoldErle = 100;
30 constexpr int kPointsToAccumulate = 6;
31 } // namespace
32
FullBandErleEstimator(const EchoCanceller3Config::Erle & config,size_t num_capture_channels)33 FullBandErleEstimator::FullBandErleEstimator(
34 const EchoCanceller3Config::Erle& config,
35 size_t num_capture_channels)
36 : min_erle_log2_(FastApproxLog2f(config.min + kEpsilon)),
37 max_erle_lf_log2_(FastApproxLog2f(config.max_l + kEpsilon)),
38 hold_counters_instantaneous_erle_(num_capture_channels, 0),
39 erle_time_domain_log2_(num_capture_channels, min_erle_log2_),
40 instantaneous_erle_(num_capture_channels, ErleInstantaneous(config)),
41 linear_filters_qualities_(num_capture_channels) {
42 Reset();
43 }
44
45 FullBandErleEstimator::~FullBandErleEstimator() = default;
46
Reset()47 void FullBandErleEstimator::Reset() {
48 for (auto& instantaneous_erle_ch : instantaneous_erle_) {
49 instantaneous_erle_ch.Reset();
50 }
51
52 UpdateQualityEstimates();
53 std::fill(erle_time_domain_log2_.begin(), erle_time_domain_log2_.end(),
54 min_erle_log2_);
55 std::fill(hold_counters_instantaneous_erle_.begin(),
56 hold_counters_instantaneous_erle_.end(), 0);
57 }
58
Update(rtc::ArrayView<const float> X2,rtc::ArrayView<const std::array<float,kFftLengthBy2Plus1>> Y2,rtc::ArrayView<const std::array<float,kFftLengthBy2Plus1>> E2,const std::vector<bool> & converged_filters)59 void FullBandErleEstimator::Update(
60 rtc::ArrayView<const float> X2,
61 rtc::ArrayView<const std::array<float, kFftLengthBy2Plus1>> Y2,
62 rtc::ArrayView<const std::array<float, kFftLengthBy2Plus1>> E2,
63 const std::vector<bool>& converged_filters) {
64 for (size_t ch = 0; ch < Y2.size(); ++ch) {
65 if (converged_filters[ch]) {
66 // Computes the fullband ERLE.
67 const float X2_sum = std::accumulate(X2.begin(), X2.end(), 0.0f);
68 if (X2_sum > kX2BandEnergyThreshold * X2.size()) {
69 const float Y2_sum =
70 std::accumulate(Y2[ch].begin(), Y2[ch].end(), 0.0f);
71 const float E2_sum =
72 std::accumulate(E2[ch].begin(), E2[ch].end(), 0.0f);
73 if (instantaneous_erle_[ch].Update(Y2_sum, E2_sum)) {
74 hold_counters_instantaneous_erle_[ch] = kBlocksToHoldErle;
75 erle_time_domain_log2_[ch] +=
76 0.05f * ((instantaneous_erle_[ch].GetInstErleLog2().value()) -
77 erle_time_domain_log2_[ch]);
78 erle_time_domain_log2_[ch] =
79 std::max(erle_time_domain_log2_[ch], min_erle_log2_);
80 }
81 }
82 }
83 --hold_counters_instantaneous_erle_[ch];
84 if (hold_counters_instantaneous_erle_[ch] == 0) {
85 instantaneous_erle_[ch].ResetAccumulators();
86 }
87 }
88
89 UpdateQualityEstimates();
90 }
91
Dump(const std::unique_ptr<ApmDataDumper> & data_dumper) const92 void FullBandErleEstimator::Dump(
93 const std::unique_ptr<ApmDataDumper>& data_dumper) const {
94 data_dumper->DumpRaw("aec3_fullband_erle_log2", FullbandErleLog2());
95 instantaneous_erle_[0].Dump(data_dumper);
96 }
97
UpdateQualityEstimates()98 void FullBandErleEstimator::UpdateQualityEstimates() {
99 for (size_t ch = 0; ch < instantaneous_erle_.size(); ++ch) {
100 linear_filters_qualities_[ch] =
101 instantaneous_erle_[ch].GetQualityEstimate();
102 }
103 }
104
ErleInstantaneous(const EchoCanceller3Config::Erle & config)105 FullBandErleEstimator::ErleInstantaneous::ErleInstantaneous(
106 const EchoCanceller3Config::Erle& config)
107 : clamp_inst_quality_to_zero_(config.clamp_quality_estimate_to_zero),
108 clamp_inst_quality_to_one_(config.clamp_quality_estimate_to_one) {
109 Reset();
110 }
111
112 FullBandErleEstimator::ErleInstantaneous::~ErleInstantaneous() = default;
113
Update(const float Y2_sum,const float E2_sum)114 bool FullBandErleEstimator::ErleInstantaneous::Update(const float Y2_sum,
115 const float E2_sum) {
116 bool update_estimates = false;
117 E2_acum_ += E2_sum;
118 Y2_acum_ += Y2_sum;
119 num_points_++;
120 if (num_points_ == kPointsToAccumulate) {
121 if (E2_acum_ > 0.f) {
122 update_estimates = true;
123 erle_log2_ = FastApproxLog2f(Y2_acum_ / E2_acum_ + kEpsilon);
124 }
125 num_points_ = 0;
126 E2_acum_ = 0.f;
127 Y2_acum_ = 0.f;
128 }
129
130 if (update_estimates) {
131 UpdateMaxMin();
132 UpdateQualityEstimate();
133 }
134 return update_estimates;
135 }
136
Reset()137 void FullBandErleEstimator::ErleInstantaneous::Reset() {
138 ResetAccumulators();
139 max_erle_log2_ = -10.f; // -30 dB.
140 min_erle_log2_ = 33.f; // 100 dB.
141 inst_quality_estimate_ = 0.f;
142 }
143
ResetAccumulators()144 void FullBandErleEstimator::ErleInstantaneous::ResetAccumulators() {
145 erle_log2_ = absl::nullopt;
146 inst_quality_estimate_ = 0.f;
147 num_points_ = 0;
148 E2_acum_ = 0.f;
149 Y2_acum_ = 0.f;
150 }
151
Dump(const std::unique_ptr<ApmDataDumper> & data_dumper) const152 void FullBandErleEstimator::ErleInstantaneous::Dump(
153 const std::unique_ptr<ApmDataDumper>& data_dumper) const {
154 data_dumper->DumpRaw("aec3_fullband_erle_inst_log2",
155 erle_log2_ ? *erle_log2_ : -10.f);
156 data_dumper->DumpRaw(
157 "aec3_erle_instantaneous_quality",
158 GetQualityEstimate() ? GetQualityEstimate().value() : 0.f);
159 data_dumper->DumpRaw("aec3_fullband_erle_max_log2", max_erle_log2_);
160 data_dumper->DumpRaw("aec3_fullband_erle_min_log2", min_erle_log2_);
161 }
162
UpdateMaxMin()163 void FullBandErleEstimator::ErleInstantaneous::UpdateMaxMin() {
164 RTC_DCHECK(erle_log2_);
165 // Adding the forgetting factors for the maximum and minimum and capping the
166 // result to the incoming value.
167 max_erle_log2_ -= 0.0004f; // Forget factor, approx 1dB every 3 sec.
168 max_erle_log2_ = std::max(max_erle_log2_, erle_log2_.value());
169 min_erle_log2_ += 0.0004f; // Forget factor, approx 1dB every 3 sec.
170 min_erle_log2_ = std::min(min_erle_log2_, erle_log2_.value());
171 }
172
UpdateQualityEstimate()173 void FullBandErleEstimator::ErleInstantaneous::UpdateQualityEstimate() {
174 const float alpha = 0.07f;
175 float quality_estimate = 0.f;
176 RTC_DCHECK(erle_log2_);
177 // TODO(peah): Currently, the estimate can become be less than 0; this should
178 // be corrected.
179 if (max_erle_log2_ > min_erle_log2_) {
180 quality_estimate = (erle_log2_.value() - min_erle_log2_) /
181 (max_erle_log2_ - min_erle_log2_);
182 }
183 if (quality_estimate > inst_quality_estimate_) {
184 inst_quality_estimate_ = quality_estimate;
185 } else {
186 inst_quality_estimate_ +=
187 alpha * (quality_estimate - inst_quality_estimate_);
188 }
189 }
190
191 } // namespace webrtc
192