blob: c1909f3b90bc59fc85bdaee8470656b8136c2404 [file] [log] [blame]
/*
* 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/subtractor.h"
#include <algorithm>
#include <numeric>
#include "api/array_view.h"
#include "modules/audio_processing/logging/apm_data_dumper.h"
#include "rtc_base/checks.h"
#include "rtc_base/safe_minmax.h"
namespace webrtc {
namespace {
void PredictionError(const Aec3Fft& fft,
const FftData& S,
rtc::ArrayView<const float> y,
std::array<float, kBlockSize>* e,
FftData* E,
std::array<float, kBlockSize>* s) {
std::array<float, kFftLength> s_scratch;
fft.Ifft(S, &s_scratch);
constexpr float kScale = 1.0f / kFftLengthBy2;
std::transform(y.begin(), y.end(), s_scratch.begin() + kFftLengthBy2,
e->begin(), [&](float a, float b) { return a - b * kScale; });
std::for_each(e->begin(), e->end(),
[](float& a) { a = rtc::SafeClamp(a, -32768.f, 32767.f); });
fft.ZeroPaddedFft(*e, E);
if (s) {
for (size_t k = 0; k < s->size(); ++k) {
(*s)[k] = kScale * s_scratch[k + kFftLengthBy2];
}
}
}
} // namespace
Subtractor::Subtractor(ApmDataDumper* data_dumper,
Aec3Optimization optimization)
: fft_(),
data_dumper_(data_dumper),
optimization_(optimization),
main_filter_(kAdaptiveFilterLength, optimization, data_dumper_),
shadow_filter_(kAdaptiveFilterLength, optimization, data_dumper_) {
RTC_DCHECK(data_dumper_);
}
Subtractor::~Subtractor() = default;
void Subtractor::HandleEchoPathChange(
const EchoPathVariability& echo_path_variability) {
if (echo_path_variability.delay_change) {
main_filter_.HandleEchoPathChange();
shadow_filter_.HandleEchoPathChange();
G_main_.HandleEchoPathChange();
G_shadow_.HandleEchoPathChange();
converged_filter_ = false;
}
}
void Subtractor::Process(const RenderBuffer& render_buffer,
const rtc::ArrayView<const float> capture,
const RenderSignalAnalyzer& render_signal_analyzer,
const AecState& aec_state,
SubtractorOutput* output) {
RTC_DCHECK_EQ(kBlockSize, capture.size());
rtc::ArrayView<const float> y = capture;
FftData& E_main = output->E_main;
FftData E_shadow;
std::array<float, kBlockSize>& e_main = output->e_main;
std::array<float, kBlockSize>& e_shadow = output->e_shadow;
FftData S;
FftData& G = S;
// Form the output of the main filter.
main_filter_.Filter(render_buffer, &S);
PredictionError(fft_, S, y, &e_main, &E_main, &output->s_main);
// Form the output of the shadow filter.
shadow_filter_.Filter(render_buffer, &S);
PredictionError(fft_, S, y, &e_shadow, &E_shadow, nullptr);
if (!converged_filter_) {
const auto sum_of_squares = [](float a, float b) { return a + b * b; };
const float e2_main =
std::accumulate(e_main.begin(), e_main.end(), 0.f, sum_of_squares);
const float e2_shadow =
std::accumulate(e_shadow.begin(), e_shadow.end(), 0.f, sum_of_squares);
const float y2 = std::accumulate(y.begin(), y.end(), 0.f, sum_of_squares);
if (y2 > kBlockSize * 50.f * 50.f) {
converged_filter_ = (e2_main > 0.3 * y2 || e2_shadow > 0.1 * y2);
}
}
// Compute spectra for future use.
E_main.Spectrum(optimization_, &output->E2_main);
E_shadow.Spectrum(optimization_, &output->E2_shadow);
// Update the main filter.
G_main_.Compute(render_buffer, render_signal_analyzer, *output, main_filter_,
aec_state.SaturatedCapture(), &G);
main_filter_.Adapt(render_buffer, G);
data_dumper_->DumpRaw("aec3_subtractor_G_main", G.re);
data_dumper_->DumpRaw("aec3_subtractor_G_main", G.im);
// Update the shadow filter.
G_shadow_.Compute(render_buffer, render_signal_analyzer, E_shadow,
shadow_filter_.SizePartitions(),
aec_state.SaturatedCapture(), &G);
shadow_filter_.Adapt(render_buffer, G);
data_dumper_->DumpRaw("aec3_subtractor_G_shadow", G.re);
data_dumper_->DumpRaw("aec3_subtractor_G_shadow", G.im);
main_filter_.DumpFilter("aec3_subtractor_H_main");
shadow_filter_.DumpFilter("aec3_subtractor_H_shadow");
}
} // namespace webrtc