diff options
Diffstat (limited to 'webrtc/modules/audio_processing/ns/noise_suppressor.h')
-rw-r--r-- | webrtc/modules/audio_processing/ns/noise_suppressor.h | 83 |
1 files changed, 83 insertions, 0 deletions
diff --git a/webrtc/modules/audio_processing/ns/noise_suppressor.h b/webrtc/modules/audio_processing/ns/noise_suppressor.h new file mode 100644 index 0000000..d962886 --- /dev/null +++ b/webrtc/modules/audio_processing/ns/noise_suppressor.h @@ -0,0 +1,83 @@ +/* + * 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_NS_NOISE_SUPPRESSOR_H_ +#define MODULES_AUDIO_PROCESSING_NS_NOISE_SUPPRESSOR_H_ + +#include <memory> +#include <vector> + +#include "api/array_view.h" +#include "modules/audio_processing/audio_buffer.h" +#include "modules/audio_processing/ns/noise_estimator.h" +#include "modules/audio_processing/ns/ns_common.h" +#include "modules/audio_processing/ns/ns_config.h" +#include "modules/audio_processing/ns/ns_fft.h" +#include "modules/audio_processing/ns/speech_probability_estimator.h" +#include "modules/audio_processing/ns/wiener_filter.h" + +namespace webrtc { + +// Class for suppressing noise in a signal. +class NoiseSuppressor { + public: + NoiseSuppressor(const NsConfig& config, + size_t sample_rate_hz, + size_t num_channels); + NoiseSuppressor(const NoiseSuppressor&) = delete; + NoiseSuppressor& operator=(const NoiseSuppressor&) = delete; + + // Analyses the signal (typically applied before the AEC to avoid analyzing + // any comfort noise signal). + void Analyze(const AudioBuffer& audio); + + // Applies noise suppression. + void Process(AudioBuffer* audio); + + private: + const size_t num_bands_; + const size_t num_channels_; + const SuppressionParams suppression_params_; + int32_t num_analyzed_frames_ = -1; + NrFft fft_; + + struct ChannelState { + ChannelState(const SuppressionParams& suppression_params, size_t num_bands); + + SpeechProbabilityEstimator speech_probability_estimator; + WienerFilter wiener_filter; + NoiseEstimator noise_estimator; + std::array<float, kFftSizeBy2Plus1> prev_analysis_signal_spectrum; + std::array<float, kFftSize - kNsFrameSize> analyze_analysis_memory; + std::array<float, kOverlapSize> process_analysis_memory; + std::array<float, kOverlapSize> process_synthesis_memory; + std::vector<std::array<float, kOverlapSize>> process_delay_memory; + }; + + struct FilterBankState { + std::array<float, kFftSize> real; + std::array<float, kFftSize> imag; + std::array<float, kFftSize> extended_frame; + }; + + std::vector<FilterBankState> filter_bank_states_heap_; + std::vector<float> upper_band_gains_heap_; + std::vector<float> energies_before_filtering_heap_; + std::vector<float> gain_adjustments_heap_; + std::vector<std::unique_ptr<ChannelState>> channels_; + + // Aggregates the Wiener filters into a single filter to use. + void AggregateWienerFilters( + rtc::ArrayView<float, kFftSizeBy2Plus1> filter) const; +}; + +} // namespace webrtc + +#endif // MODULES_AUDIO_PROCESSING_NS_NOISE_SUPPRESSOR_H_ |