webrtc_m130/modules/audio_processing/echo_cancellation_impl.h

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/*
* Copyright (c) 2012 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.
*/
#ifndef MODULES_AUDIO_PROCESSING_ECHO_CANCELLATION_IMPL_H_
#define MODULES_AUDIO_PROCESSING_ECHO_CANCELLATION_IMPL_H_
#include <memory>
#include <vector>
#include "modules/audio_processing/include/audio_processing.h"
#include "rtc_base/constructormagic.h"
#include "rtc_base/criticalsection.h"
namespace webrtc {
class AudioBuffer;
class EchoCancellationImpl : public EchoCancellation {
public:
EchoCancellationImpl(rtc::CriticalSection* crit_render,
rtc::CriticalSection* crit_capture);
~EchoCancellationImpl() override;
void ProcessRenderAudio(rtc::ArrayView<const float> packed_render_audio);
int ProcessCaptureAudio(AudioBuffer* audio, int stream_delay_ms);
// EchoCancellation implementation.
bool is_enabled() const override;
int stream_drift_samples() const override;
SuppressionLevel suppression_level() const override;
bool is_drift_compensation_enabled() const override;
void Initialize(int sample_rate_hz,
size_t num_reverse_channels_,
size_t num_output_channels_,
size_t num_proc_channels_);
void SetExtraOptions(const webrtc::Config& config);
bool is_delay_agnostic_enabled() const;
bool is_extended_filter_enabled() const;
std::string GetExperimentsDescription();
Added support in the AEC for refined filter adaptation. The following algorithmic functionality was added: -Add support for an exact regressor power to be computed which avoids the issue with the updating of the filter sometimes being unstable. -Lowered the fixed step size of the adaptive filter to 0.05 which significantly reduces the sensitivity of the adaptive filter to near-end noise, nonlinearities, doubletalk and the unmodelled echo path tail. It also reduces the tracking speed of the adaptive filter but the chosen value proved to give a sufficient tradeoff for the requirements on the adaptive filter. To allow the new functionality to be selectively applied the following was done: -A new Config was added for selectively activating the functionality. -Functionality was added in the audioprocessing and echocancellationimpl classes for passing the activation of the functionality down to the AEC algorithms. To make the code for the introduction of the functionality clean, the following refactoring was done: -The selection of the step size was moved to a single place. -The constant for the step size of the adaptive filter in extended filter mode was made local. -The state variable storing the step-size was renamed to a more describing name. When the new functionality is not activated, the changes have been tested for bitexactness on Linux. TBR=minyue@webrtc.org BUG=webrtc:5778, webrtc:5777 Review URL: https://codereview.webrtc.org/1887003002 Cr-Commit-Position: refs/heads/master@{#12384}
2016-04-15 11:23:33 -07:00
bool is_refined_adaptive_filter_enabled() const;
// Returns the system delay of the first AEC component.
int GetSystemDelayInSamples() const;
static void PackRenderAudioBuffer(const AudioBuffer* audio,
size_t num_output_channels,
size_t num_channels,
std::vector<float>* packed_buffer);
static size_t NumCancellersRequired(size_t num_output_channels,
size_t num_reverse_channels);
// Enable logging of various AEC statistics.
int enable_metrics(bool enable) override;
// Provides various statistics about the AEC.
int GetMetrics(Metrics* metrics) override;
// Enable logging of delay metrics.
int enable_delay_logging(bool enable) override;
// Provides delay metrics.
int GetDelayMetrics(int* median,
int* std,
float* fraction_poor_delays) override;
private:
class Canceller;
struct StreamProperties;
// EchoCancellation implementation.
int Enable(bool enable) override;
int enable_drift_compensation(bool enable) override;
void set_stream_drift_samples(int drift) override;
int set_suppression_level(SuppressionLevel level) override;
bool are_metrics_enabled() const override;
bool stream_has_echo() const override;
bool is_delay_logging_enabled() const override;
int GetDelayMetrics(int* median, int* std) override;
struct AecCore* aec_core() const override;
void AllocateRenderQueue();
int Configure();
rtc::CriticalSection* const crit_render_ RTC_ACQUIRED_BEFORE(crit_capture_);
rtc::CriticalSection* const crit_capture_;
bool enabled_ = false;
bool drift_compensation_enabled_ RTC_GUARDED_BY(crit_capture_);
bool metrics_enabled_ RTC_GUARDED_BY(crit_capture_);
SuppressionLevel suppression_level_ RTC_GUARDED_BY(crit_capture_);
int stream_drift_samples_ RTC_GUARDED_BY(crit_capture_);
bool was_stream_drift_set_ RTC_GUARDED_BY(crit_capture_);
bool stream_has_echo_ RTC_GUARDED_BY(crit_capture_);
bool delay_logging_enabled_ RTC_GUARDED_BY(crit_capture_);
bool extended_filter_enabled_ RTC_GUARDED_BY(crit_capture_);
bool delay_agnostic_enabled_ RTC_GUARDED_BY(crit_capture_);
bool refined_adaptive_filter_enabled_ RTC_GUARDED_BY(crit_capture_) = false;
std::vector<std::unique_ptr<Canceller>> cancellers_;
std::unique_ptr<StreamProperties> stream_properties_;
RTC_DISALLOW_IMPLICIT_CONSTRUCTORS(EchoCancellationImpl);
};
} // namespace webrtc
#endif // MODULES_AUDIO_PROCESSING_ECHO_CANCELLATION_IMPL_H_