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Diffstat (limited to 'third_party/libwebrtc/modules/audio_processing/ns/noise_estimator.h')
-rw-r--r-- | third_party/libwebrtc/modules/audio_processing/ns/noise_estimator.h | 77 |
1 files changed, 77 insertions, 0 deletions
diff --git a/third_party/libwebrtc/modules/audio_processing/ns/noise_estimator.h b/third_party/libwebrtc/modules/audio_processing/ns/noise_estimator.h new file mode 100644 index 0000000000..0c0466a679 --- /dev/null +++ b/third_party/libwebrtc/modules/audio_processing/ns/noise_estimator.h @@ -0,0 +1,77 @@ +/* + * Copyright (c) 2019 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_ESTIMATOR_H_ +#define MODULES_AUDIO_PROCESSING_NS_NOISE_ESTIMATOR_H_ + +#include <array> + +#include "api/array_view.h" +#include "modules/audio_processing/ns/ns_common.h" +#include "modules/audio_processing/ns/quantile_noise_estimator.h" +#include "modules/audio_processing/ns/suppression_params.h" + +namespace webrtc { + +// Class for estimating the spectral characteristics of the noise in an incoming +// signal. +class NoiseEstimator { + public: + explicit NoiseEstimator(const SuppressionParams& suppression_params); + + // Prepare the estimator for analysis of a new frame. + void PrepareAnalysis(); + + // Performs the first step of the estimator update. + void PreUpdate(int32_t num_analyzed_frames, + rtc::ArrayView<const float, kFftSizeBy2Plus1> signal_spectrum, + float signal_spectral_sum); + + // Performs the second step of the estimator update. + void PostUpdate( + rtc::ArrayView<const float> speech_probability, + rtc::ArrayView<const float, kFftSizeBy2Plus1> signal_spectrum); + + // Returns the noise spectral estimate. + rtc::ArrayView<const float, kFftSizeBy2Plus1> get_noise_spectrum() const { + return noise_spectrum_; + } + + // Returns the noise from the previous frame. + rtc::ArrayView<const float, kFftSizeBy2Plus1> get_prev_noise_spectrum() + const { + return prev_noise_spectrum_; + } + + // Returns a noise spectral estimate based on white and pink noise parameters. + rtc::ArrayView<const float, kFftSizeBy2Plus1> get_parametric_noise_spectrum() + const { + return parametric_noise_spectrum_; + } + rtc::ArrayView<const float, kFftSizeBy2Plus1> + get_conservative_noise_spectrum() const { + return conservative_noise_spectrum_; + } + + private: + const SuppressionParams& suppression_params_; + float white_noise_level_ = 0.f; + float pink_noise_numerator_ = 0.f; + float pink_noise_exp_ = 0.f; + std::array<float, kFftSizeBy2Plus1> prev_noise_spectrum_; + std::array<float, kFftSizeBy2Plus1> conservative_noise_spectrum_; + std::array<float, kFftSizeBy2Plus1> parametric_noise_spectrum_; + std::array<float, kFftSizeBy2Plus1> noise_spectrum_; + QuantileNoiseEstimator quantile_noise_estimator_; +}; + +} // namespace webrtc + +#endif // MODULES_AUDIO_PROCESSING_NS_NOISE_ESTIMATOR_H_ |