echo_remover.cc | Explore in Territory

/*
 *  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 <stddef.h>

#include <algorithm>
#include <array>
#include <atomic>
#include <cmath>
#include <memory>

#include "api/array_view.h"
#include "modules/audio_processing/aec3/aec3_common.h"
#include "modules/audio_processing/aec3/aec3_fft.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/render_buffer.h"
#include "modules/audio_processing/aec3/render_signal_analyzer.h"
#include "modules/audio_processing/aec3/residual_echo_estimator.h"
#include "modules/audio_processing/aec3/subtractor.h"
#include "modules/audio_processing/aec3/subtractor_output.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/checks.h"
#include "rtc_base/logging.h"

namespace webrtc {

namespace {

// Maximum number of channels for which the capture channel data is stored on
// the stack. If the number of channels are larger than this, they are stored
// using scratch memory that is pre-allocated on the heap. The reason for this
// partitioning is not to waste heap space for handling the more common numbers
// of channels, while at the same time not limiting the support for higher
// numbers of channels by enforcing the capture channel data to be stored on the
// stack using a fixed maximum value.
constexpr size_t kMaxNumChannelsOnStack = …;

// Chooses the number of channels to store on the heap when that is required due
// to the number of capture channels being larger than the pre-defined number
// of channels to store on the stack.
size_t NumChannelsOnHeap(size_t num_capture_channels) { … }

void LinearEchoPower(const FftData& E,
                     const FftData& Y,
                     std::array<float, kFftLengthBy2Plus1>* S2) { … }

// Fades between two input signals using a fix-sized transition.
void SignalTransition(rtc::ArrayView<const float> from,
                      rtc::ArrayView<const float> to,
                      rtc::ArrayView<float> out) { … }

// Computes a windowed (square root Hanning) padded FFT and updates the related
// memory.
void WindowedPaddedFft(const Aec3Fft& fft,
                       rtc::ArrayView<const float> v,
                       rtc::ArrayView<float> v_old,
                       FftData* V) { … }

// Class for removing the echo from the capture signal.
class EchoRemoverImpl final : public EchoRemover { … };

std::atomic<int> EchoRemoverImpl::instance_count_(0);

EchoRemoverImpl::EchoRemoverImpl(const EchoCanceller3Config& config,
                                 int sample_rate_hz,
                                 size_t num_render_channels,
                                 size_t num_capture_channels)
    : … { … }

EchoRemoverImpl::~EchoRemoverImpl() = default;

void EchoRemoverImpl::GetMetrics(EchoControl::Metrics* metrics) const { … }

void EchoRemoverImpl::ProcessCapture(
    EchoPathVariability echo_path_variability,
    bool capture_signal_saturation,
    const absl::optional<DelayEstimate>& external_delay,
    RenderBuffer* render_buffer,
    Block* linear_output,
    Block* capture) { … }

void EchoRemoverImpl::FormLinearFilterOutput(
    const SubtractorOutput& subtractor_output,
    rtc::ArrayView<float> output) { … }

}  // namespace

EchoRemover* EchoRemover::Create(const EchoCanceller3Config& config,
                                 int sample_rate_hz,
                                 size_t num_render_channels,
                                 size_t num_capture_channels) { … }

}  // namespace webrtc
chromium/third_party/webrtc/modules/audio_processing/aec3/echo_remover.cc
