webrtc/modules/audio_processing/aec3/echo_remover.cc
Per Åhgren 971de07713 Corrected the detection of narrowband render signals
This CL corrects the bug that only looked at narrowband
render signals above 900 Hz and only assumed that the
influence of such lasted for 6 blocks, which resulted
in filter divergence and echo leakage.


Bug: webrtc:9008,chromium:821670
Change-Id: I9b2635d24b260e9d9a8c5c088ab663e03fb93c42
Reviewed-on: https://webrtc-review.googlesource.com/61800
Commit-Queue: Per Åhgren <peah@webrtc.org>
Reviewed-by: Ivo Creusen <ivoc@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#22434}
2018-03-15 08:50:56 +00:00

257 lines
10 KiB
C++

/*
* 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/echo_remover.h"
#include <math.h>
#include <algorithm>
#include <memory>
#include <numeric>
#include <string>
#include "api/array_view.h"
#include "modules/audio_processing/aec3/aec3_common.h"
#include "modules/audio_processing/aec3/aec_state.h"
#include "modules/audio_processing/aec3/comfort_noise_generator.h"
#include "modules/audio_processing/aec3/echo_path_variability.h"
#include "modules/audio_processing/aec3/echo_remover_metrics.h"
#include "modules/audio_processing/aec3/fft_data.h"
#include "modules/audio_processing/aec3/output_selector.h"
#include "modules/audio_processing/aec3/render_buffer.h"
#include "modules/audio_processing/aec3/render_delay_buffer.h"
#include "modules/audio_processing/aec3/residual_echo_estimator.h"
#include "modules/audio_processing/aec3/subtractor.h"
#include "modules/audio_processing/aec3/suppression_filter.h"
#include "modules/audio_processing/aec3/suppression_gain.h"
#include "modules/audio_processing/logging/apm_data_dumper.h"
#include "rtc_base/atomicops.h"
#include "rtc_base/constructormagic.h"
namespace webrtc {
namespace {
void LinearEchoPower(const FftData& E,
const FftData& Y,
std::array<float, kFftLengthBy2Plus1>* S2) {
for (size_t k = 0; k < E.re.size(); ++k) {
(*S2)[k] = (Y.re[k] - E.re[k]) * (Y.re[k] - E.re[k]) +
(Y.im[k] - E.im[k]) * (Y.im[k] - E.im[k]);
}
}
// Class for removing the echo from the capture signal.
class EchoRemoverImpl final : public EchoRemover {
public:
explicit EchoRemoverImpl(const EchoCanceller3Config& config,
int sample_rate_hz);
~EchoRemoverImpl() override;
void GetMetrics(EchoControl::Metrics* metrics) const override;
// Removes the echo from a block of samples from the capture signal. The
// supplied render signal is assumed to be pre-aligned with the capture
// signal.
void ProcessCapture(const EchoPathVariability& echo_path_variability,
bool capture_signal_saturation,
const rtc::Optional<DelayEstimate>& delay_estimate,
RenderBuffer* render_buffer,
std::vector<std::vector<float>>* capture) override;
// Updates the status on whether echo leakage is detected in the output of the
// echo remover.
void UpdateEchoLeakageStatus(bool leakage_detected) override {
echo_leakage_detected_ = leakage_detected;
}
private:
static int instance_count_;
const EchoCanceller3Config config_;
const Aec3Fft fft_;
std::unique_ptr<ApmDataDumper> data_dumper_;
const Aec3Optimization optimization_;
const int sample_rate_hz_;
Subtractor subtractor_;
SuppressionGain suppression_gain_;
ComfortNoiseGenerator cng_;
SuppressionFilter suppression_filter_;
RenderSignalAnalyzer render_signal_analyzer_;
OutputSelector output_selector_;
ResidualEchoEstimator residual_echo_estimator_;
bool echo_leakage_detected_ = false;
AecState aec_state_;
EchoRemoverMetrics metrics_;
bool initial_state_ = true;
RTC_DISALLOW_COPY_AND_ASSIGN(EchoRemoverImpl);
};
int EchoRemoverImpl::instance_count_ = 0;
EchoRemoverImpl::EchoRemoverImpl(const EchoCanceller3Config& config,
int sample_rate_hz)
: config_(config),
fft_(),
data_dumper_(
new ApmDataDumper(rtc::AtomicOps::Increment(&instance_count_))),
optimization_(DetectOptimization()),
sample_rate_hz_(sample_rate_hz),
subtractor_(config, data_dumper_.get(), optimization_),
suppression_gain_(config_, optimization_),
cng_(optimization_),
suppression_filter_(sample_rate_hz_),
render_signal_analyzer_(config_),
residual_echo_estimator_(config_),
aec_state_(config_) {
RTC_DCHECK(ValidFullBandRate(sample_rate_hz));
}
EchoRemoverImpl::~EchoRemoverImpl() = default;
void EchoRemoverImpl::GetMetrics(EchoControl::Metrics* metrics) const {
// Echo return loss (ERL) is inverted to go from gain to attenuation.
metrics->echo_return_loss = -10.0 * log10(aec_state_.ErlTimeDomain());
metrics->echo_return_loss_enhancement =
10.0 * log10(aec_state_.ErleTimeDomain());
}
void EchoRemoverImpl::ProcessCapture(
const EchoPathVariability& echo_path_variability,
bool capture_signal_saturation,
const rtc::Optional<DelayEstimate>& delay_estimate,
RenderBuffer* render_buffer,
std::vector<std::vector<float>>* capture) {
const std::vector<std::vector<float>>& x = render_buffer->Block(0);
std::vector<std::vector<float>>* y = capture;
RTC_DCHECK(render_buffer);
RTC_DCHECK(y);
RTC_DCHECK_EQ(x.size(), NumBandsForRate(sample_rate_hz_));
RTC_DCHECK_EQ(y->size(), NumBandsForRate(sample_rate_hz_));
RTC_DCHECK_EQ(x[0].size(), kBlockSize);
RTC_DCHECK_EQ((*y)[0].size(), kBlockSize);
const std::vector<float>& x0 = x[0];
std::vector<float>& y0 = (*y)[0];
data_dumper_->DumpWav("aec3_echo_remover_capture_input", kBlockSize, &y0[0],
LowestBandRate(sample_rate_hz_), 1);
data_dumper_->DumpWav("aec3_echo_remover_render_input", kBlockSize, &x0[0],
LowestBandRate(sample_rate_hz_), 1);
data_dumper_->DumpRaw("aec3_echo_remover_capture_input", y0);
data_dumper_->DumpRaw("aec3_echo_remover_render_input", x0);
aec_state_.UpdateCaptureSaturation(capture_signal_saturation);
if (echo_path_variability.AudioPathChanged()) {
subtractor_.HandleEchoPathChange(echo_path_variability);
aec_state_.HandleEchoPathChange(echo_path_variability);
initial_state_ = true;
}
std::array<float, kFftLengthBy2Plus1> Y2;
std::array<float, kFftLengthBy2Plus1> R2;
std::array<float, kFftLengthBy2Plus1> S2_linear;
std::array<float, kFftLengthBy2Plus1> G;
float high_bands_gain;
FftData Y;
FftData comfort_noise;
FftData high_band_comfort_noise;
SubtractorOutput subtractor_output;
FftData& E_main_nonwindowed = subtractor_output.E_main_nonwindowed;
auto& E2_main = subtractor_output.E2_main_nonwindowed;
auto& E2_shadow = subtractor_output.E2_shadow;
auto& e_main = subtractor_output.e_main;
// Analyze the render signal.
render_signal_analyzer_.Update(*render_buffer, aec_state_.FilterDelay());
// Perform linear echo cancellation.
if (initial_state_ && !aec_state_.InitialState()) {
subtractor_.ExitInitialState();
initial_state_ = false;
}
subtractor_.Process(*render_buffer, y0, render_signal_analyzer_, aec_state_,
&subtractor_output);
// Compute spectra.
// fft_.ZeroPaddedFft(y0, Aec3Fft::Window::kHanning, &Y);
fft_.ZeroPaddedFft(y0, Aec3Fft::Window::kRectangular, &Y);
LinearEchoPower(E_main_nonwindowed, Y, &S2_linear);
Y.Spectrum(optimization_, Y2);
// Update the AEC state information.
aec_state_.Update(delay_estimate, subtractor_.FilterFrequencyResponse(),
subtractor_.FilterImpulseResponse(),
subtractor_.ConvergedFilter(), *render_buffer, E2_main, Y2,
subtractor_output.s_main, echo_leakage_detected_);
// Choose the linear output.
output_selector_.FormLinearOutput(!aec_state_.TransparentMode(), e_main, y0);
data_dumper_->DumpWav("aec3_output_linear", kBlockSize, &y0[0],
LowestBandRate(sample_rate_hz_), 1);
data_dumper_->DumpRaw("aec3_output_linear", y0);
const auto& E2 = output_selector_.UseSubtractorOutput() ? E2_main : Y2;
// Estimate the residual echo power.
residual_echo_estimator_.Estimate(aec_state_, *render_buffer, S2_linear, Y2,
&R2);
// Estimate the comfort noise.
cng_.Compute(aec_state_, Y2, &comfort_noise, &high_band_comfort_noise);
// A choose and apply echo suppression gain.
suppression_gain_.GetGain(E2, R2, cng_.NoiseSpectrum(),
render_signal_analyzer_, aec_state_, x,
&high_bands_gain, &G);
suppression_filter_.ApplyGain(comfort_noise, high_band_comfort_noise, G,
high_bands_gain, y);
// Update the metrics.
metrics_.Update(aec_state_, cng_.NoiseSpectrum(), G);
// Update the aec state with the aec output characteristics.
aec_state_.UpdateWithOutput(y0);
// Debug outputs for the purpose of development and analysis.
data_dumper_->DumpWav("aec3_echo_estimate", kBlockSize,
&subtractor_output.s_main[0],
LowestBandRate(sample_rate_hz_), 1);
data_dumper_->DumpRaw("aec3_output", y0);
data_dumper_->DumpRaw("aec3_narrow_render",
render_signal_analyzer_.NarrowPeakBand() ? 1 : 0);
data_dumper_->DumpRaw("aec3_N2", cng_.NoiseSpectrum());
data_dumper_->DumpRaw("aec3_suppressor_gain", G);
data_dumper_->DumpWav("aec3_output",
rtc::ArrayView<const float>(&y0[0], kBlockSize),
LowestBandRate(sample_rate_hz_), 1);
data_dumper_->DumpRaw("aec3_using_subtractor_output",
output_selector_.UseSubtractorOutput() ? 1 : 0);
data_dumper_->DumpRaw("aec3_E2", E2);
data_dumper_->DumpRaw("aec3_E2_main", E2_main);
data_dumper_->DumpRaw("aec3_E2_shadow", E2_shadow);
data_dumper_->DumpRaw("aec3_S2_linear", S2_linear);
data_dumper_->DumpRaw("aec3_Y2", Y2);
data_dumper_->DumpRaw("aec3_X2", render_buffer->Spectrum(0));
data_dumper_->DumpRaw("aec3_R2", R2);
data_dumper_->DumpRaw("aec3_erle", aec_state_.Erle());
data_dumper_->DumpRaw("aec3_erl", aec_state_.Erl());
data_dumper_->DumpRaw("aec3_usable_linear_estimate",
aec_state_.UsableLinearEstimate());
data_dumper_->DumpRaw("aec3_filter_delay", aec_state_.FilterDelay());
data_dumper_->DumpRaw("aec3_capture_saturation",
aec_state_.SaturatedCapture() ? 1 : 0);
}
} // namespace
EchoRemover* EchoRemover::Create(const EchoCanceller3Config& config,
int sample_rate_hz) {
return new EchoRemoverImpl(config, sample_rate_hz);
}
} // namespace webrtc