pitch_based_vad.h - mozsearch

Enable keyboard shortcuts

/*

 *  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_VAD_PITCH_BASED_VAD_H_

#define MODULES_AUDIO_PROCESSING_VAD_PITCH_BASED_VAD_H_

#include <memory>

#include "modules/audio_processing/vad/common.h"

#include "modules/audio_processing/vad/gmm.h"

namespace webrtc {

class VadCircularBuffer;

// Computes the probability of the input audio frame to be active given

// the corresponding pitch-gain and lag of the frame.

class PitchBasedVad {

 public:

  PitchBasedVad();

  ~PitchBasedVad();

  // Compute pitch-based voicing probability, given the features.

  //   features: a structure containing features required for computing voicing

  //             probabilities.

//

  //   p_combined: an array which contains the combined activity probabilities

  //               computed prior to the call of this function. The method,

  //               then, computes the voicing probabilities and combine them

  //               with the given values. The result are returned in `p`.

  int VoicingProbability(const AudioFeatures& features, double* p_combined);

 private:

  int UpdatePrior(double p);

  // TODO(turajs): maybe defining this at a higher level (maybe enum) so that

  // all the code recognize it as "no-error."

  static const int kNoError = 0;

  GmmParameters noise_gmm_;

  GmmParameters voice_gmm_;

  double p_prior_;

  std::unique_ptr<VadCircularBuffer> circular_buffer_;

};

}  // namespace webrtc

#endif  // MODULES_AUDIO_PROCESSING_VAD_PITCH_BASED_VAD_H_