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