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fullband_erle_estimator.cc (6715B)


      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 <array>
     15 #include <cstddef>
     16 #include <memory>
     17 #include <numeric>
     18 #include <optional>
     19 #include <vector>
     20 
     21 #include "api/array_view.h"
     22 #include "api/audio/echo_canceller3_config.h"
     23 #include "modules/audio_processing/aec3/aec3_common.h"
     24 #include "modules/audio_processing/logging/apm_data_dumper.h"
     25 #include "rtc_base/checks.h"
     26 
     27 namespace webrtc {
     28 
     29 namespace {
     30 constexpr float kEpsilon = 1e-3f;
     31 constexpr float kX2BandEnergyThreshold = 44015068.0f;
     32 constexpr int kBlocksToHoldErle = 100;
     33 constexpr int kPointsToAccumulate = 6;
     34 }  // namespace
     35 
     36 FullBandErleEstimator::FullBandErleEstimator(
     37    const EchoCanceller3Config::Erle& config,
     38    size_t num_capture_channels)
     39    : min_erle_log2_(FastApproxLog2f(config.min + kEpsilon)),
     40      max_erle_lf_log2_(FastApproxLog2f(config.max_l + kEpsilon)),
     41      hold_counters_instantaneous_erle_(num_capture_channels, 0),
     42      erle_time_domain_log2_(num_capture_channels, min_erle_log2_),
     43      instantaneous_erle_(num_capture_channels, ErleInstantaneous(config)),
     44      linear_filters_qualities_(num_capture_channels) {
     45  Reset();
     46 }
     47 
     48 FullBandErleEstimator::~FullBandErleEstimator() = default;
     49 
     50 void FullBandErleEstimator::Reset() {
     51  for (auto& instantaneous_erle_ch : instantaneous_erle_) {
     52    instantaneous_erle_ch.Reset();
     53  }
     54 
     55  UpdateQualityEstimates();
     56  std::fill(erle_time_domain_log2_.begin(), erle_time_domain_log2_.end(),
     57            min_erle_log2_);
     58  std::fill(hold_counters_instantaneous_erle_.begin(),
     59            hold_counters_instantaneous_erle_.end(), 0);
     60 }
     61 
     62 void FullBandErleEstimator::Update(
     63    ArrayView<const float> X2,
     64    ArrayView<const std::array<float, kFftLengthBy2Plus1>> Y2,
     65    ArrayView<const std::array<float, kFftLengthBy2Plus1>> E2,
     66    const std::vector<bool>& converged_filters) {
     67  for (size_t ch = 0; ch < Y2.size(); ++ch) {
     68    if (converged_filters[ch]) {
     69      // Computes the fullband ERLE.
     70      const float X2_sum = std::accumulate(X2.begin(), X2.end(), 0.0f);
     71      if (X2_sum > kX2BandEnergyThreshold * X2.size()) {
     72        const float Y2_sum =
     73            std::accumulate(Y2[ch].begin(), Y2[ch].end(), 0.0f);
     74        const float E2_sum =
     75            std::accumulate(E2[ch].begin(), E2[ch].end(), 0.0f);
     76        if (instantaneous_erle_[ch].Update(Y2_sum, E2_sum)) {
     77          hold_counters_instantaneous_erle_[ch] = kBlocksToHoldErle;
     78          erle_time_domain_log2_[ch] +=
     79              0.05f * ((instantaneous_erle_[ch].GetInstErleLog2().value()) -
     80                       erle_time_domain_log2_[ch]);
     81          erle_time_domain_log2_[ch] =
     82              std::max(erle_time_domain_log2_[ch], min_erle_log2_);
     83        }
     84      }
     85    }
     86    --hold_counters_instantaneous_erle_[ch];
     87    if (hold_counters_instantaneous_erle_[ch] == 0) {
     88      instantaneous_erle_[ch].ResetAccumulators();
     89    }
     90  }
     91 
     92  UpdateQualityEstimates();
     93 }
     94 
     95 void FullBandErleEstimator::Dump(
     96    const std::unique_ptr<ApmDataDumper>& data_dumper) const {
     97  data_dumper->DumpRaw("aec3_fullband_erle_log2", FullbandErleLog2());
     98  instantaneous_erle_[0].Dump(data_dumper);
     99 }
    100 
    101 void FullBandErleEstimator::UpdateQualityEstimates() {
    102  for (size_t ch = 0; ch < instantaneous_erle_.size(); ++ch) {
    103    linear_filters_qualities_[ch] =
    104        instantaneous_erle_[ch].GetQualityEstimate();
    105  }
    106 }
    107 
    108 FullBandErleEstimator::ErleInstantaneous::ErleInstantaneous(
    109    const EchoCanceller3Config::Erle& config)
    110    : clamp_inst_quality_to_zero_(config.clamp_quality_estimate_to_zero),
    111      clamp_inst_quality_to_one_(config.clamp_quality_estimate_to_one) {
    112  Reset();
    113 }
    114 
    115 FullBandErleEstimator::ErleInstantaneous::~ErleInstantaneous() = default;
    116 
    117 bool FullBandErleEstimator::ErleInstantaneous::Update(const float Y2_sum,
    118                                                      const float E2_sum) {
    119  bool update_estimates = false;
    120  E2_acum_ += E2_sum;
    121  Y2_acum_ += Y2_sum;
    122  num_points_++;
    123  if (num_points_ == kPointsToAccumulate) {
    124    if (E2_acum_ > 0.f) {
    125      update_estimates = true;
    126      erle_log2_ = FastApproxLog2f(Y2_acum_ / E2_acum_ + kEpsilon);
    127    }
    128    num_points_ = 0;
    129    E2_acum_ = 0.f;
    130    Y2_acum_ = 0.f;
    131  }
    132 
    133  if (update_estimates) {
    134    UpdateMaxMin();
    135    UpdateQualityEstimate();
    136  }
    137  return update_estimates;
    138 }
    139 
    140 void FullBandErleEstimator::ErleInstantaneous::Reset() {
    141  ResetAccumulators();
    142  max_erle_log2_ = -10.f;  // -30 dB.
    143  min_erle_log2_ = 33.f;   // 100 dB.
    144  inst_quality_estimate_ = 0.f;
    145 }
    146 
    147 void FullBandErleEstimator::ErleInstantaneous::ResetAccumulators() {
    148  erle_log2_ = std::nullopt;
    149  inst_quality_estimate_ = 0.f;
    150  num_points_ = 0;
    151  E2_acum_ = 0.f;
    152  Y2_acum_ = 0.f;
    153 }
    154 
    155 void FullBandErleEstimator::ErleInstantaneous::Dump(
    156    const std::unique_ptr<ApmDataDumper>& data_dumper) const {
    157  data_dumper->DumpRaw("aec3_fullband_erle_inst_log2",
    158                       erle_log2_ ? *erle_log2_ : -10.f);
    159  data_dumper->DumpRaw(
    160      "aec3_erle_instantaneous_quality",
    161      GetQualityEstimate() ? GetQualityEstimate().value() : 0.f);
    162  data_dumper->DumpRaw("aec3_fullband_erle_max_log2", max_erle_log2_);
    163  data_dumper->DumpRaw("aec3_fullband_erle_min_log2", min_erle_log2_);
    164 }
    165 
    166 void FullBandErleEstimator::ErleInstantaneous::UpdateMaxMin() {
    167  RTC_DCHECK(erle_log2_);
    168  // Adding the forgetting factors for the maximum and minimum and capping the
    169  // result to the incoming value.
    170  max_erle_log2_ -= 0.0004f;  // Forget factor, approx 1dB every 3 sec.
    171  max_erle_log2_ = std::max(max_erle_log2_, erle_log2_.value());
    172  min_erle_log2_ += 0.0004f;  // Forget factor, approx 1dB every 3 sec.
    173  min_erle_log2_ = std::min(min_erle_log2_, erle_log2_.value());
    174 }
    175 
    176 void FullBandErleEstimator::ErleInstantaneous::UpdateQualityEstimate() {
    177  const float alpha = 0.07f;
    178  float quality_estimate = 0.f;
    179  RTC_DCHECK(erle_log2_);
    180  // TODO(peah): Currently, the estimate can become be less than 0; this should
    181  // be corrected.
    182  if (max_erle_log2_ > min_erle_log2_) {
    183    quality_estimate = (erle_log2_.value() - min_erle_log2_) /
    184                       (max_erle_log2_ - min_erle_log2_);
    185  }
    186  if (quality_estimate > inst_quality_estimate_) {
    187    inst_quality_estimate_ = quality_estimate;
    188  } else {
    189    inst_quality_estimate_ +=
    190        alpha * (quality_estimate - inst_quality_estimate_);
    191  }
    192 }
    193 
    194 }  // namespace webrtc