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