Line data    Source code

       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 WEBRTC_MODULES_AUDIO_PROCESSING_LEVEL_CONTROLLER_SIGNAL_CLASSIFIER_H_
      12             : #define WEBRTC_MODULES_AUDIO_PROCESSING_LEVEL_CONTROLLER_SIGNAL_CLASSIFIER_H_
      13             : 
      14             : #include <memory>
      15             : #include <vector>
      16             : 
      17             : #include "webrtc/base/array_view.h"
      18             : #include "webrtc/base/constructormagic.h"
      19             : #include "webrtc/modules/audio_processing/level_controller/down_sampler.h"
      20             : #include "webrtc/modules/audio_processing/level_controller/noise_spectrum_estimator.h"
      21             : #include "webrtc/modules/audio_processing/utility/ooura_fft.h"
      22             : 
      23             : namespace webrtc {
      24             : 
      25             : class ApmDataDumper;
      26             : class AudioBuffer;
      27             : 
      28             : class SignalClassifier {
      29             :  public:
      30             :   enum class SignalType { kHighlyNonStationary, kNonStationary, kStationary };
      31             : 
      32             :   explicit SignalClassifier(ApmDataDumper* data_dumper);
      33             :   ~SignalClassifier();
      34             : 
      35             :   void Initialize(int sample_rate_hz);
      36             :   void Analyze(const AudioBuffer& audio, SignalType* signal_type);
      37             : 
      38             :  private:
      39           0 :   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  // WEBRTC_MODULES_AUDIO_PROCESSING_LEVEL_CONTROLLER_SIGNAL_CLASSIFIER_H_