1 /*
2  *  Copyright (c) 2013 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_coding/neteq/post_decode_vad.h"
12 
13 namespace webrtc {
14 
~PostDecodeVad()15 PostDecodeVad::~PostDecodeVad() {
16   if (vad_instance_)
17     WebRtcVad_Free(vad_instance_);
18 }
19 
Enable()20 void PostDecodeVad::Enable() {
21   if (!vad_instance_) {
22     // Create the instance.
23     vad_instance_ = WebRtcVad_Create();
24     if (vad_instance_ == nullptr) {
25       // Failed to create instance.
26       Disable();
27       return;
28     }
29   }
30   Init();
31   enabled_ = true;
32 }
33 
Disable()34 void PostDecodeVad::Disable() {
35   enabled_ = false;
36   running_ = false;
37 }
38 
Init()39 void PostDecodeVad::Init() {
40   running_ = false;
41   if (vad_instance_) {
42     WebRtcVad_Init(vad_instance_);
43     WebRtcVad_set_mode(vad_instance_, kVadMode);
44     running_ = true;
45   }
46 }
47 
Update(int16_t * signal,size_t length,AudioDecoder::SpeechType speech_type,bool sid_frame,int fs_hz)48 void PostDecodeVad::Update(int16_t* signal, size_t length,
49                            AudioDecoder::SpeechType speech_type,
50                            bool sid_frame,
51                            int fs_hz) {
52   if (!vad_instance_ || !enabled_) {
53     return;
54   }
55 
56   if (speech_type == AudioDecoder::kComfortNoise || sid_frame ||
57       fs_hz > 16000) {
58     // TODO(hlundin): Remove restriction on fs_hz.
59     running_ = false;
60     active_speech_ = true;
61     sid_interval_counter_ = 0;
62   } else if (!running_) {
63     ++sid_interval_counter_;
64   }
65 
66   if (sid_interval_counter_ >= kVadAutoEnable) {
67     Init();
68   }
69 
70   if (length > 0 && running_) {
71     size_t vad_sample_index = 0;
72     active_speech_ = false;
73     // Loop through frame sizes 30, 20, and 10 ms.
74     for (int vad_frame_size_ms = 30; vad_frame_size_ms >= 10;
75         vad_frame_size_ms -= 10) {
76       size_t vad_frame_size_samples =
77           static_cast<size_t>(vad_frame_size_ms * fs_hz / 1000);
78       while (length - vad_sample_index >= vad_frame_size_samples) {
79         int vad_return = WebRtcVad_Process(
80             vad_instance_, fs_hz, &signal[vad_sample_index],
81             vad_frame_size_samples);
82         active_speech_ |= (vad_return == 1);
83         vad_sample_index += vad_frame_size_samples;
84       }
85     }
86   }
87 }
88 
89 }  // namespace webrtc
90