suppression_gain.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/suppression_gain.h"

#include <math.h>
#include <stddef.h>

#include <algorithm>
#include <numeric>

#include "modules/audio_processing/aec3/dominant_nearend_detector.h"
#include "modules/audio_processing/aec3/moving_average.h"
#include "modules/audio_processing/aec3/subband_nearend_detector.h"
#include "modules/audio_processing/aec3/vector_math.h"
#include "modules/audio_processing/logging/apm_data_dumper.h"
#include "rtc_base/checks.h"
#include "system_wrappers/include/field_trial.h"

namespace webrtc {
namespace {

void LimitLowFrequencyGains(std::array<float, kFftLengthBy2Plus1>* gain) { … }

void LimitHighFrequencyGains(bool conservative_hf_suppression,
                             std::array<float, kFftLengthBy2Plus1>* gain) { … }

// Scales the echo according to assessed audibility at the other end.
void WeightEchoForAudibility(const EchoCanceller3Config& config,
                             rtc::ArrayView<const float> echo,
                             rtc::ArrayView<float> weighted_echo) { … }

}  // namespace

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

float SuppressionGain::UpperBandsGain(
    rtc::ArrayView<const std::array<float, kFftLengthBy2Plus1>> echo_spectrum,
    rtc::ArrayView<const std::array<float, kFftLengthBy2Plus1>>
        comfort_noise_spectrum,
    const absl::optional<int>& narrow_peak_band,
    bool saturated_echo,
    const Block& render,
    const std::array<float, kFftLengthBy2Plus1>& low_band_gain) const { … }

// Computes the gain to reduce the echo to a non audible level.
void SuppressionGain::GainToNoAudibleEcho(
    const std::array<float, kFftLengthBy2Plus1>& nearend,
    const std::array<float, kFftLengthBy2Plus1>& echo,
    const std::array<float, kFftLengthBy2Plus1>& masker,
    std::array<float, kFftLengthBy2Plus1>* gain) const { … }

// Compute the minimum gain as the attenuating gain to put the signal just
// above the zero sample values.
void SuppressionGain::GetMinGain(
    rtc::ArrayView<const float> weighted_residual_echo,
    rtc::ArrayView<const float> last_nearend,
    rtc::ArrayView<const float> last_echo,
    bool low_noise_render,
    bool saturated_echo,
    rtc::ArrayView<float> min_gain) const { … }

// Compute the maximum gain by limiting the gain increase from the previous
// gain.
void SuppressionGain::GetMaxGain(rtc::ArrayView<float> max_gain) const { … }

void SuppressionGain::LowerBandGain(
    bool low_noise_render,
    const AecState& aec_state,
    rtc::ArrayView<const std::array<float, kFftLengthBy2Plus1>>
        suppressor_input,
    rtc::ArrayView<const std::array<float, kFftLengthBy2Plus1>> residual_echo,
    rtc::ArrayView<const std::array<float, kFftLengthBy2Plus1>> comfort_noise,
    bool clock_drift,
    std::array<float, kFftLengthBy2Plus1>* gain) { … }

SuppressionGain::SuppressionGain(const EchoCanceller3Config& config,
                                 Aec3Optimization optimization,
                                 int sample_rate_hz,
                                 size_t num_capture_channels)
    : … { … }

SuppressionGain::~SuppressionGain() = default;

void SuppressionGain::GetGain(
    rtc::ArrayView<const std::array<float, kFftLengthBy2Plus1>>
        nearend_spectrum,
    rtc::ArrayView<const std::array<float, kFftLengthBy2Plus1>> echo_spectrum,
    rtc::ArrayView<const std::array<float, kFftLengthBy2Plus1>>
        residual_echo_spectrum,
    rtc::ArrayView<const std::array<float, kFftLengthBy2Plus1>>
        residual_echo_spectrum_unbounded,
    rtc::ArrayView<const std::array<float, kFftLengthBy2Plus1>>
        comfort_noise_spectrum,
    const RenderSignalAnalyzer& render_signal_analyzer,
    const AecState& aec_state,
    const Block& render,
    bool clock_drift,
    float* high_bands_gain,
    std::array<float, kFftLengthBy2Plus1>* low_band_gain) { … }

void SuppressionGain::SetInitialState(bool state) { … }

// Detects when the render signal can be considered to have low power and
// consist of stationary noise.
bool SuppressionGain::LowNoiseRenderDetector::Detect(const Block& render) { … }

SuppressionGain::GainParameters::GainParameters(
    int last_lf_band,
    int first_hf_band,
    const EchoCanceller3Config::Suppressor::Tuning& tuning)
    : … { … }

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