1 /* 2 * Copyright (c) 2016 The WebRTC project authors. All Rights Reserved. 3 * 4 * Use of this source code is governed by a BSD-style license 5 * that can be found in the LICENSE file in the root of the source 6 * tree. An additional intellectual property rights grant can be found 7 * in the file PATENTS. All contributing project authors may 8 * be found in the AUTHORS file in the root of the source tree. 9 */ 10 11 #ifndef MODULES_AUDIO_PROCESSING_AGC2_SIGNAL_CLASSIFIER_H_ 12 #define MODULES_AUDIO_PROCESSING_AGC2_SIGNAL_CLASSIFIER_H_ 13 14 #include <memory> 15 #include <vector> 16 17 #include "api/array_view.h" 18 #include "common_audio/third_party/ooura/fft_size_128/ooura_fft.h" 19 #include "modules/audio_processing/agc2/down_sampler.h" 20 #include "modules/audio_processing/agc2/noise_spectrum_estimator.h" 21 #include "rtc_base/constructor_magic.h" 22 23 namespace webrtc { 24 25 class ApmDataDumper; 26 class AudioBuffer; 27 28 class SignalClassifier { 29 public: 30 enum class SignalType { kNonStationary, kStationary }; 31 32 explicit SignalClassifier(ApmDataDumper* data_dumper); 33 ~SignalClassifier(); 34 35 void Initialize(int sample_rate_hz); 36 SignalType Analyze(rtc::ArrayView<const float> signal); 37 38 private: 39 class FrameExtender { 40 public: 41 FrameExtender(size_t frame_size, size_t extended_frame_size); 42 ~FrameExtender(); 43 44 void ExtendFrame(rtc::ArrayView<const float> x, 45 rtc::ArrayView<float> x_extended); 46 47 private: 48 std::vector<float> x_old_; 49 50 RTC_DISALLOW_IMPLICIT_CONSTRUCTORS(FrameExtender); 51 }; 52 53 ApmDataDumper* const data_dumper_; 54 DownSampler down_sampler_; 55 std::unique_ptr<FrameExtender> frame_extender_; 56 NoiseSpectrumEstimator noise_spectrum_estimator_; 57 int sample_rate_hz_; 58 int initialization_frames_left_; 59 int consistent_classification_counter_; 60 SignalType last_signal_type_; 61 const OouraFft ooura_fft_; 62 RTC_DISALLOW_IMPLICIT_CONSTRUCTORS(SignalClassifier); 63 }; 64 65 } // namespace webrtc 66 67 #endif // MODULES_AUDIO_PROCESSING_AGC2_SIGNAL_CLASSIFIER_H_ 68