blob: d8cb7a76315f26624a106540d75e69a39cecd725 [file] [log] [blame]
/*
* Copyright (c) 2018 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/subband_erle_estimator.h"
#include <algorithm>
#include <memory>
#include "absl/types/optional.h"
#include "api/array_view.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"
#include "system_wrappers/include/field_trial.h"
namespace webrtc {
namespace {
constexpr int kPointsToAccumulate = 6;
constexpr float kX2BandEnergyThreshold = 44015068.0f;
constexpr int kErleHold = 100;
constexpr int kBlocksForOnsetDetection = kErleHold + 150;
bool EnableAdaptErleOnLowRender() {
return !field_trial::IsEnabled("WebRTC-Aec3AdaptErleOnLowRenderKillSwitch");
}
} // namespace
SubbandErleEstimator::SubbandErleEstimator(float min_erle,
float max_erle_lf,
float max_erle_hf)
: min_erle_(min_erle),
max_erle_lf_(max_erle_lf),
max_erle_hf_(max_erle_hf),
adapt_on_low_render_(EnableAdaptErleOnLowRender()) {
Reset();
}
SubbandErleEstimator::~SubbandErleEstimator() = default;
void SubbandErleEstimator::Reset() {
erle_.fill(min_erle_);
erle_onsets_.fill(min_erle_);
hold_counters_.fill(0);
coming_onset_.fill(true);
}
void SubbandErleEstimator::Update(rtc::ArrayView<const float> X2,
rtc::ArrayView<const float> Y2,
rtc::ArrayView<const float> E2,
bool converged_filter,
bool onset_detection) {
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;
UpdateBands(X2, Y2, E2, 1, kFftLengthBy4, max_erle_lf_, onset_detection);
UpdateBands(X2, Y2, E2, kFftLengthBy4, kFftLengthBy2, max_erle_hf_,
onset_detection);
}
if (onset_detection) {
DecreaseErlePerBandForLowRenderSignals();
}
erle_[0] = erle_[1];
erle_[kFftLengthBy2] = erle_[kFftLengthBy2 - 1];
}
void SubbandErleEstimator::Dump(
const std::unique_ptr<ApmDataDumper>& data_dumper) const {
data_dumper->DumpRaw("aec3_erle", Erle());
data_dumper->DumpRaw("aec3_erle_onset", ErleOnsets());
}
void SubbandErleEstimator::UpdateBands(rtc::ArrayView<const float> X2,
rtc::ArrayView<const float> Y2,
rtc::ArrayView<const float> E2,
size_t start,
size_t stop,
float max_erle,
bool onset_detection) {
auto erle_band_update = [](float erle_band, float new_erle,
bool low_render_energy, float alpha_inc,
float alpha_dec, float min_erle, float max_erle) {
if (new_erle < erle_band && low_render_energy) {
// Decreases are not allowed if low render energy signals were used for
// the erle computation.
return erle_band;
}
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;
};
for (size_t k = start; k < stop; ++k) {
if (adapt_on_low_render_ || X2[k] > kX2BandEnergyThreshold) {
bool low_render_energy = false;
absl::optional<float> new_erle = instantaneous_erle_.Update(
X2[k], Y2[k], E2[k], k, &low_render_energy);
if (new_erle) {
RTC_DCHECK(adapt_on_low_render_ || !low_render_energy);
if (onset_detection && !low_render_energy) {
if (coming_onset_[k]) {
coming_onset_[k] = false;
erle_onsets_[k] = erle_band_update(
erle_onsets_[k], new_erle.value(), low_render_energy, 0.15f,
0.3f, min_erle_, max_erle);
}
hold_counters_[k] = kBlocksForOnsetDetection;
}
erle_[k] =
erle_band_update(erle_[k], new_erle.value(), low_render_energy,
0.05f, 0.1f, min_erle_, max_erle);
}
}
}
}
void SubbandErleEstimator::DecreaseErlePerBandForLowRenderSignals() {
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;
}
}
}
}
SubbandErleEstimator::ErleInstantaneous::ErleInstantaneous() {
Reset();
}
SubbandErleEstimator::ErleInstantaneous::~ErleInstantaneous() = default;
absl::optional<float> SubbandErleEstimator::ErleInstantaneous::Update(
float X2,
float Y2,
float E2,
size_t band,
bool* low_render_energy) {
absl::optional<float> erle_instantaneous = absl::nullopt;
RTC_DCHECK_LT(band, kFftLengthBy2Plus1);
Y2_acum_[band] += Y2;
E2_acum_[band] += E2;
low_render_energy_[band] =
low_render_energy_[band] || X2 < kX2BandEnergyThreshold;
if (++num_points_[band] == kPointsToAccumulate) {
if (E2_acum_[band]) {
erle_instantaneous = Y2_acum_[band] / E2_acum_[band];
}
*low_render_energy = low_render_energy_[band];
num_points_[band] = 0;
Y2_acum_[band] = 0.f;
E2_acum_[band] = 0.f;
low_render_energy_[band] = false;
}
return erle_instantaneous;
}
void SubbandErleEstimator::ErleInstantaneous::Reset() {
Y2_acum_.fill(0.f);
E2_acum_.fill(0.f);
low_render_energy_.fill(false);
num_points_.fill(0);
}
} // namespace webrtc