| /* |
| * 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 |