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 #include "webrtc/modules/audio_processing/vad/standalone_vad.h" 12 13 #include <assert.h> 14 15 #include "webrtc/modules/include/module_common_types.h" 16 #include "webrtc/modules/utility/include/audio_frame_operations.h" 17 #include "webrtc/typedefs.h" 18 19 namespace webrtc { 20 21 static const int kDefaultStandaloneVadMode = 3; 22 23 StandaloneVad::StandaloneVad(VadInst* vad) 24 : vad_(vad), buffer_(), index_(0), mode_(kDefaultStandaloneVadMode) { 25 } 26 27 StandaloneVad::~StandaloneVad() { 28 WebRtcVad_Free(vad_); 29 } 30 31 StandaloneVad* StandaloneVad::Create() { 32 VadInst* vad = WebRtcVad_Create(); 33 if (!vad) 34 return nullptr; 35 36 int err = WebRtcVad_Init(vad); 37 err |= WebRtcVad_set_mode(vad, kDefaultStandaloneVadMode); 38 if (err != 0) { 39 WebRtcVad_Free(vad); 40 return nullptr; 41 } 42 return new StandaloneVad(vad); 43 } 44 45 int StandaloneVad::AddAudio(const int16_t* data, size_t length) { 46 if (length != kLength10Ms) 47 return -1; 48 49 if (index_ + length > kLength10Ms * kMaxNum10msFrames) 50 // Reset the buffer if it's full. 51 // TODO(ajm): Instead, consider just processing every 10 ms frame. Then we 52 // can forgo the buffering. 53 index_ = 0; 54 55 memcpy(&buffer_[index_], data, sizeof(int16_t) * length); 56 index_ += length; 57 return 0; 58 } 59 60 int StandaloneVad::GetActivity(double* p, size_t length_p) { 61 if (index_ == 0) 62 return -1; 63 64 const size_t num_frames = index_ / kLength10Ms; 65 if (num_frames > length_p) 66 return -1; 67 assert(WebRtcVad_ValidRateAndFrameLength(kSampleRateHz, index_) == 0); 68 69 int activity = WebRtcVad_Process(vad_, kSampleRateHz, buffer_, index_); 70 if (activity < 0) 71 return -1; 72 else if (activity == 0) 73 p[0] = 0.01; // Arbitrary but small and non-zero. 74 else 75 p[0] = 0.5; // 0.5 is neutral values when combinned by other probabilities. 76 for (size_t n = 1; n < num_frames; n++) 77 p[n] = p[0]; 78 // Reset the buffer to start from the beginning. 79 index_ = 0; 80 return activity; 81 } 82 83 int StandaloneVad::set_mode(int mode) { 84 if (mode < 0 || mode > 3) 85 return -1; 86 if (WebRtcVad_set_mode(vad_, mode) != 0) 87 return -1; 88 89 mode_ = mode; 90 return 0; 91 } 92 93 } // namespace webrtc 94
