OLD | NEW |
| (Empty) |
1 // Copyright 2013 The Chromium Authors. All rights reserved. | |
2 // Use of this source code is governed by a BSD-style license that can be | |
3 // found in the LICENSE file. | |
4 | |
5 #include "webkit/renderer/media/webaudiosourceprovider_impl.h" | |
6 | |
7 #include <vector> | |
8 | |
9 #include "base/logging.h" | |
10 #include "third_party/WebKit/public/web/WebAudioSourceProviderClient.h" | |
11 | |
12 using WebKit::WebVector; | |
13 | |
14 namespace webkit_media { | |
15 | |
16 namespace { | |
17 | |
18 // Simple helper class for Try() locks. Lock is Try()'d on construction and | |
19 // must be checked via the locked() attribute. If acquisition was successful | |
20 // the lock will be released upon destruction. | |
21 // TODO(dalecurtis): This should probably move to base/ if others start using | |
22 // this pattern. | |
23 class AutoTryLock { | |
24 public: | |
25 explicit AutoTryLock(base::Lock& lock) | |
26 : lock_(lock), | |
27 acquired_(lock_.Try()) {} | |
28 | |
29 bool locked() const { return acquired_; } | |
30 | |
31 ~AutoTryLock() { | |
32 if (acquired_) { | |
33 lock_.AssertAcquired(); | |
34 lock_.Release(); | |
35 } | |
36 } | |
37 | |
38 private: | |
39 base::Lock& lock_; | |
40 const bool acquired_; | |
41 DISALLOW_COPY_AND_ASSIGN(AutoTryLock); | |
42 }; | |
43 | |
44 } // namespace | |
45 | |
46 WebAudioSourceProviderImpl::WebAudioSourceProviderImpl( | |
47 const scoped_refptr<media::AudioRendererSink>& sink) | |
48 : channels_(0), | |
49 sample_rate_(0), | |
50 volume_(1.0), | |
51 state_(kStopped), | |
52 renderer_(NULL), | |
53 client_(NULL), | |
54 sink_(sink) { | |
55 } | |
56 | |
57 WebAudioSourceProviderImpl::~WebAudioSourceProviderImpl() {} | |
58 | |
59 void WebAudioSourceProviderImpl::setClient( | |
60 WebKit::WebAudioSourceProviderClient* client) { | |
61 base::AutoLock auto_lock(sink_lock_); | |
62 if (client && client != client_) { | |
63 // Detach the audio renderer from normal playback. | |
64 sink_->Stop(); | |
65 | |
66 // The client will now take control by calling provideInput() periodically. | |
67 client_ = client; | |
68 | |
69 if (renderer_) { | |
70 // The client needs to be notified of the audio format, if available. | |
71 // If the format is not yet available, we'll be notified later | |
72 // when Initialize() is called. | |
73 | |
74 // Inform WebKit about the audio stream format. | |
75 client->setFormat(channels_, sample_rate_); | |
76 } | |
77 } else if (!client && client_) { | |
78 // Restore normal playback. | |
79 client_ = NULL; | |
80 sink_->SetVolume(volume_); | |
81 if (state_ >= kStarted) | |
82 sink_->Start(); | |
83 if (state_ >= kPlaying) | |
84 sink_->Play(); | |
85 } | |
86 } | |
87 | |
88 void WebAudioSourceProviderImpl::provideInput( | |
89 const WebVector<float*>& audio_data, size_t number_of_frames) { | |
90 if (!bus_wrapper_ || | |
91 static_cast<size_t>(bus_wrapper_->channels()) != audio_data.size()) { | |
92 bus_wrapper_ = media::AudioBus::CreateWrapper(audio_data.size()); | |
93 } | |
94 | |
95 bus_wrapper_->set_frames(number_of_frames); | |
96 for (size_t i = 0; i < audio_data.size(); ++i) | |
97 bus_wrapper_->SetChannelData(i, audio_data[i]); | |
98 | |
99 // Use a try lock to avoid contention in the real-time audio thread. | |
100 AutoTryLock auto_try_lock(sink_lock_); | |
101 if (!auto_try_lock.locked() || state_ != kPlaying) { | |
102 // Provide silence if we failed to acquire the lock or the source is not | |
103 // running. | |
104 bus_wrapper_->Zero(); | |
105 return; | |
106 } | |
107 | |
108 DCHECK(renderer_); | |
109 DCHECK(client_); | |
110 DCHECK_EQ(channels_, bus_wrapper_->channels()); | |
111 renderer_->Render(bus_wrapper_.get(), 0); | |
112 bus_wrapper_->Scale(volume_); | |
113 } | |
114 | |
115 void WebAudioSourceProviderImpl::Start() { | |
116 base::AutoLock auto_lock(sink_lock_); | |
117 DCHECK_EQ(state_, kStopped); | |
118 state_ = kStarted; | |
119 if (!client_) | |
120 sink_->Start(); | |
121 } | |
122 | |
123 void WebAudioSourceProviderImpl::Stop() { | |
124 base::AutoLock auto_lock(sink_lock_); | |
125 state_ = kStopped; | |
126 if (!client_) | |
127 sink_->Stop(); | |
128 } | |
129 | |
130 void WebAudioSourceProviderImpl::Play() { | |
131 base::AutoLock auto_lock(sink_lock_); | |
132 DCHECK_EQ(state_, kStarted); | |
133 state_ = kPlaying; | |
134 if (!client_) | |
135 sink_->Play(); | |
136 } | |
137 | |
138 void WebAudioSourceProviderImpl::Pause() { | |
139 base::AutoLock auto_lock(sink_lock_); | |
140 DCHECK(state_ == kPlaying || state_ == kStarted); | |
141 state_ = kStarted; | |
142 if (!client_) | |
143 sink_->Pause(); | |
144 } | |
145 | |
146 bool WebAudioSourceProviderImpl::SetVolume(double volume) { | |
147 base::AutoLock auto_lock(sink_lock_); | |
148 volume_ = volume; | |
149 if (!client_) | |
150 sink_->SetVolume(volume); | |
151 return true; | |
152 } | |
153 | |
154 void WebAudioSourceProviderImpl::Initialize( | |
155 const media::AudioParameters& params, | |
156 RenderCallback* renderer) { | |
157 base::AutoLock auto_lock(sink_lock_); | |
158 CHECK(!renderer_); | |
159 renderer_ = renderer; | |
160 | |
161 DCHECK_EQ(state_, kStopped); | |
162 sink_->Initialize(params, renderer); | |
163 | |
164 // Keep track of the format in case the client hasn't yet been set. | |
165 channels_ = params.channels(); | |
166 sample_rate_ = params.sample_rate(); | |
167 | |
168 if (client_) { | |
169 // Inform WebKit about the audio stream format. | |
170 client_->setFormat(channels_, sample_rate_); | |
171 } | |
172 } | |
173 | |
174 } // namespace webkit_media | |
OLD | NEW |