| /* |
| * Copyright (c) 2017 The WebRTC project authors. All Rights Reserved. |
| * |
| * Use of this source code is governed by a BSD-style license |
| * that can be found in the LICENSE file in the root of the source |
| * tree. An additional intellectual property rights grant can be found |
| * in the file PATENTS. All contributing project authors may |
| * be found in the AUTHORS file in the root of the source tree. |
| */ |
| |
| #include "modules/audio_processing/aec3/erle_estimator.h" |
| |
| #include <algorithm> |
| #include <numeric> |
| |
| #include "absl/types/optional.h" |
| #include "modules/audio_processing/aec3/aec3_common.h" |
| #include "modules/audio_processing/logging/apm_data_dumper.h" |
| #include "rtc_base/numerics/safe_minmax.h" |
| |
| namespace webrtc { |
| |
| namespace { |
| constexpr int kPointsToAccumulate = 6; |
| constexpr float kEpsilon = 1e-3f; |
| } // namespace |
| |
| ErleEstimator::ErleEstimator(float min_erle, |
| float max_erle_lf, |
| float max_erle_hf) |
| : min_erle_(min_erle), |
| min_erle_log2_(FastApproxLog2f(min_erle_ + kEpsilon)), |
| max_erle_lf_(max_erle_lf), |
| max_erle_lf_log2(FastApproxLog2f(max_erle_lf_ + kEpsilon)), |
| max_erle_hf_(max_erle_hf), |
| erle_freq_inst_(kPointsToAccumulate), |
| erle_time_inst_(kPointsToAccumulate) { |
| Reset(); |
| } |
| |
| ErleEstimator::~ErleEstimator() = default; |
| |
| void ErleEstimator::Reset() { |
| erle_time_inst_.Reset(); |
| erle_.fill(min_erle_); |
| erle_onsets_.fill(min_erle_); |
| hold_counters_.fill(0); |
| coming_onset_.fill(true); |
| erle_time_domain_log2_ = min_erle_log2_; |
| hold_counter_time_domain_ = 0; |
| } |
| |
| ErleEstimator::ErleTimeInstantaneous::ErleTimeInstantaneous( |
| int points_to_accumulate) |
| : points_to_accumulate_(points_to_accumulate) { |
| Reset(); |
| } |
| ErleEstimator::ErleTimeInstantaneous::~ErleTimeInstantaneous() = default; |
| |
| bool ErleEstimator::ErleTimeInstantaneous::Update(const float Y2_sum, |
| const float E2_sum) { |
| bool ret = false; |
| E2_acum_ += E2_sum; |
| Y2_acum_ += Y2_sum; |
| num_points_++; |
| if (num_points_ == points_to_accumulate_) { |
| if (E2_acum_ > 0.f) { |
| ret = true; |
| erle_log2_ = FastApproxLog2f(Y2_acum_ / E2_acum_ + kEpsilon); |
| } |
| num_points_ = 0; |
| E2_acum_ = 0.f; |
| Y2_acum_ = 0.f; |
| } |
| |
| if (ret) { |
| UpdateMaxMin(); |
| UpdateQualityEstimate(); |
| } |
| return ret; |
| } |
| |
| void ErleEstimator::ErleTimeInstantaneous::Reset() { |
| ResetAccumulators(); |
| max_erle_log2_ = -10.f; // -30 dB. |
| min_erle_log2_ = 33.f; // 100 dB. |
| inst_quality_estimate_ = 0.f; |
| } |
| |
| void ErleEstimator::ErleTimeInstantaneous::ResetAccumulators() { |
| erle_log2_ = absl::nullopt; |
| inst_quality_estimate_ = 0.f; |
| num_points_ = 0; |
| E2_acum_ = 0.f; |
| Y2_acum_ = 0.f; |
| } |
| |
| void ErleEstimator::ErleTimeInstantaneous::Dump( |
| const std::unique_ptr<ApmDataDumper>& data_dumper) { |
| data_dumper->DumpRaw("aec3_erle_time_inst_log2", |
| erle_log2_ ? *erle_log2_ : -10.f); |
| data_dumper->DumpRaw( |
| "aec3_erle_time_quality", |
| GetInstQualityEstimate() ? GetInstQualityEstimate().value() : 0.f); |
| data_dumper->DumpRaw("aec3_erle_time_max_log2", max_erle_log2_); |
| data_dumper->DumpRaw("aec3_erle_time_min_log2", min_erle_log2_); |
| } |
| |
| void ErleEstimator::ErleTimeInstantaneous::UpdateMaxMin() { |
| RTC_DCHECK(erle_log2_); |
| if (erle_log2_.value() > max_erle_log2_) { |
| max_erle_log2_ = erle_log2_.value(); |
| } else { |
| max_erle_log2_ -= 0.0004; // Forget factor, approx 1dB every 3 sec. |
| } |
| |
| if (erle_log2_.value() < min_erle_log2_) { |
| min_erle_log2_ = erle_log2_.value(); |
| } else { |
| min_erle_log2_ += 0.0004; // Forget factor, approx 1dB every 3 sec. |
| } |
| } |
| |
| void ErleEstimator::ErleTimeInstantaneous::UpdateQualityEstimate() { |
| const float alpha = 0.07f; |
| float quality_estimate = 0.f; |
| RTC_DCHECK(erle_log2_); |
| if (max_erle_log2_ > min_erle_log2_) { |
| quality_estimate = (erle_log2_.value() - min_erle_log2_) / |
| (max_erle_log2_ - min_erle_log2_); |
| } |
| if (quality_estimate > inst_quality_estimate_) { |
| inst_quality_estimate_ = quality_estimate; |
| } else { |
| inst_quality_estimate_ += |
| alpha * (quality_estimate - inst_quality_estimate_); |
| } |
| } |
| |
| ErleEstimator::ErleFreqInstantaneous::ErleFreqInstantaneous( |
| int points_to_accumulate) |
| : points_to_accumulate_(points_to_accumulate) { |
| Reset(); |
| } |
| |
| ErleEstimator::ErleFreqInstantaneous::~ErleFreqInstantaneous() = default; |
| |
| absl::optional<float> |
| ErleEstimator::ErleFreqInstantaneous::Update(float Y2, float E2, size_t band) { |
| absl::optional<float> ret = absl::nullopt; |
| RTC_DCHECK_LT(band, kFftLengthBy2Plus1); |
| Y2_acum_[band] += Y2; |
| E2_acum_[band] += E2; |
| if (++num_points_[band] == points_to_accumulate_) { |
| if (E2_acum_[band]) { |
| ret = Y2_acum_[band] / E2_acum_[band]; |
| } |
| num_points_[band] = 0; |
| Y2_acum_[band] = 0.f; |
| E2_acum_[band] = 0.f; |
| } |
| |
| return ret; |
| } |
| |
| void ErleEstimator::ErleFreqInstantaneous::Reset() { |
| Y2_acum_.fill(0.f); |
| E2_acum_.fill(0.f); |
| num_points_.fill(0); |
| } |
| |
| void ErleEstimator::Update(rtc::ArrayView<const float> render_spectrum, |
| rtc::ArrayView<const float> capture_spectrum, |
| rtc::ArrayView<const float> subtractor_spectrum, |
| bool converged_filter, |
| bool onset_detection) { |
| RTC_DCHECK_EQ(kFftLengthBy2Plus1, render_spectrum.size()); |
| RTC_DCHECK_EQ(kFftLengthBy2Plus1, capture_spectrum.size()); |
| RTC_DCHECK_EQ(kFftLengthBy2Plus1, subtractor_spectrum.size()); |
| const auto& X2 = render_spectrum; |
| const auto& Y2 = capture_spectrum; |
| const auto& E2 = subtractor_spectrum; |
| |
| // Corresponds of WGN of power -46 dBFS. |
| constexpr float kX2Min = 44015068.0f; |
| |
| constexpr int kErleHold = 100; |
| constexpr int kBlocksForOnsetDetection = kErleHold + 150; |
| |
| auto erle_band_update = [](float erle_band, float new_erle, float alpha_inc, |
| float alpha_dec, float min_erle, float max_erle) { |
| float alpha = new_erle > erle_band ? alpha_inc : alpha_dec; |
| float erle_band_out = erle_band; |
| erle_band_out = erle_band + alpha * (new_erle - erle_band); |
| erle_band_out = rtc::SafeClamp(erle_band_out, min_erle, max_erle); |
| return erle_band_out; |
| }; |
| |
| // Update the estimates in a clamped minimum statistics manner. |
| auto erle_update = [&](size_t start, size_t stop, float max_erle, |
| bool onset_detection) { |
| for (size_t k = start; k < stop; ++k) { |
| if (X2[k] > kX2Min) { |
| absl::optional<float> new_erle = |
| erle_freq_inst_.Update(Y2[k], E2[k], k); |
| if (new_erle) { |
| if (onset_detection) { |
| if (coming_onset_[k]) { |
| coming_onset_[k] = false; |
| erle_onsets_[k] = |
| erle_band_update(erle_onsets_[k], new_erle.value(), 0.15f, |
| 0.3f, min_erle_, max_erle); |
| } |
| hold_counters_[k] = kBlocksForOnsetDetection; |
| } |
| erle_[k] = erle_band_update(erle_[k], new_erle.value(), 0.05f, 0.1f, |
| min_erle_, max_erle); |
| } |
| } |
| } |
| }; |
| |
| if (converged_filter) { |
| // Note that the use of the converged_filter flag already imposed |
| // a minimum of the erle that can be estimated as that flag would |
| // be false if the filter is performing poorly. |
| constexpr size_t kFftLengthBy4 = kFftLengthBy2 / 2; |
| erle_update(1, kFftLengthBy4, max_erle_lf_, onset_detection); |
| erle_update(kFftLengthBy4, kFftLengthBy2, max_erle_hf_, onset_detection); |
| } |
| |
| if (onset_detection) { |
| for (size_t k = 1; k < kFftLengthBy2; ++k) { |
| hold_counters_[k]--; |
| if (hold_counters_[k] <= (kBlocksForOnsetDetection - kErleHold)) { |
| if (erle_[k] > erle_onsets_[k]) { |
| erle_[k] = std::max(erle_onsets_[k], 0.97f * erle_[k]); |
| RTC_DCHECK_LE(min_erle_, erle_[k]); |
| } |
| if (hold_counters_[k] <= 0) { |
| coming_onset_[k] = true; |
| hold_counters_[k] = 0; |
| } |
| } |
| } |
| } |
| |
| erle_[0] = erle_[1]; |
| erle_[kFftLengthBy2] = erle_[kFftLengthBy2 - 1]; |
| |
| if (converged_filter) { |
| // Compute ERLE over all frequency bins. |
| const float X2_sum = std::accumulate(X2.begin(), X2.end(), 0.0f); |
| if (X2_sum > kX2Min * X2.size()) { |
| const float Y2_sum = std::accumulate(Y2.begin(), Y2.end(), 0.0f); |
| const float E2_sum = std::accumulate(E2.begin(), E2.end(), 0.0f); |
| if (erle_time_inst_.Update(Y2_sum, E2_sum)) { |
| hold_counter_time_domain_ = kErleHold; |
| erle_time_domain_log2_ += |
| 0.1f * ((erle_time_inst_.GetInstErle_log2().value()) - |
| erle_time_domain_log2_); |
| erle_time_domain_log2_ = rtc::SafeClamp( |
| erle_time_domain_log2_, min_erle_log2_, max_erle_lf_log2); |
| } |
| } |
| } |
| --hold_counter_time_domain_; |
| if (hold_counter_time_domain_ <= 0) { |
| erle_time_domain_log2_ = |
| std::max(min_erle_log2_, erle_time_domain_log2_ - 0.044f); |
| } |
| if (hold_counter_time_domain_ == 0) { |
| erle_time_inst_.ResetAccumulators(); |
| } |
| } |
| |
| void ErleEstimator::Dump(const std::unique_ptr<ApmDataDumper>& data_dumper) { |
| data_dumper->DumpRaw("aec3_erle", Erle()); |
| data_dumper->DumpRaw("aec3_erle_onset", ErleOnsets()); |
| data_dumper->DumpRaw("aec3_erle_time_domain_log2", ErleTimeDomainLog2()); |
| erle_time_inst_.Dump(data_dumper); |
| } |
| |
| } // namespace webrtc |