1 /* 2 * Copyright (c) 2012 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_VAD_PITCH_BASED_VAD_H_ 12 #define MODULES_AUDIO_PROCESSING_VAD_PITCH_BASED_VAD_H_ 13 14 #include <memory> 15 16 #include "modules/audio_processing/vad/common.h" 17 #include "modules/audio_processing/vad/gmm.h" 18 19 namespace webrtc { 20 21 class VadCircularBuffer; 22 23 // Computes the probability of the input audio frame to be active given 24 // the corresponding pitch-gain and lag of the frame. 25 class PitchBasedVad { 26 public: 27 PitchBasedVad(); 28 ~PitchBasedVad(); 29 30 // Compute pitch-based voicing probability, given the features. 31 // features: a structure containing features required for computing voicing 32 // probabilities. 33 // 34 // p_combined: an array which contains the combined activity probabilities 35 // computed prior to the call of this function. The method, 36 // then, computes the voicing probabilities and combine them 37 // with the given values. The result are returned in |p|. 38 int VoicingProbability(const AudioFeatures& features, double* p_combined); 39 40 private: 41 int UpdatePrior(double p); 42 43 // TODO(turajs): maybe defining this at a higher level (maybe enum) so that 44 // all the code recognize it as "no-error." 45 static const int kNoError = 0; 46 47 GmmParameters noise_gmm_; 48 GmmParameters voice_gmm_; 49 50 double p_prior_; 51 52 std::unique_ptr<VadCircularBuffer> circular_buffer_; 53 }; 54 55 } // namespace webrtc 56 57 #endif // MODULES_AUDIO_PROCESSING_VAD_PITCH_BASED_VAD_H_ 58