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1 /* | |
2 * Copyright (C) 2010 Google Inc. All rights reserved. | |
3 * | |
4 * Redistribution and use in source and binary forms, with or without | |
5 * modification, are permitted provided that the following conditions | |
6 * are met: | |
7 * | |
8 * 1. Redistributions of source code must retain the above copyright | |
9 * notice, this list of conditions and the following disclaimer. | |
10 * 2. Redistributions in binary form must reproduce the above copyright | |
11 * notice, this list of conditions and the following disclaimer in the | |
12 * documentation and/or other materials provided with the distribution. | |
13 * 3. Neither the name of Apple Computer, Inc. ("Apple") nor the names of | |
14 * its contributors may be used to endorse or promote products derived | |
15 * from this software without specific prior written permission. | |
16 * | |
17 * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY | |
18 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED | |
19 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE | |
20 * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY | |
21 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES | |
22 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; | |
23 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND | |
24 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT | |
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF | |
26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. | |
27 */ | |
28 | |
29 #include "config.h" | |
30 | |
31 #if ENABLE(WEB_AUDIO) | |
32 | |
33 #include "platform/audio/chromium/AudioDestinationChromium.h" | |
34 | |
35 #include "platform/audio/AudioFIFO.h" | |
36 #include "platform/audio/AudioPullFIFO.h" | |
37 #include "public/platform/Platform.h" | |
38 | |
39 namespace WebCore { | |
40 | |
41 // Buffer size at which the web audio engine will render. | |
42 const unsigned renderBufferSize = 128; | |
43 | |
44 // Size of the FIFO | |
45 const size_t fifoSize = 8192; | |
46 | |
47 // Factory method: Chromium-implementation | |
48 PassOwnPtr<AudioDestination> AudioDestination::create(AudioIOCallback& callback,
const String& inputDeviceId, unsigned numberOfInputChannels, unsigned numberOfO
utputChannels, float sampleRate) | |
49 { | |
50 return adoptPtr(new AudioDestinationChromium(callback, inputDeviceId, number
OfInputChannels, numberOfOutputChannels, sampleRate)); | |
51 } | |
52 | |
53 AudioDestinationChromium::AudioDestinationChromium(AudioIOCallback& callback, co
nst String& inputDeviceId, unsigned numberOfInputChannels, unsigned numberOfOutp
utChannels, float sampleRate) | |
54 : m_callback(callback) | |
55 , m_numberOfOutputChannels(numberOfOutputChannels) | |
56 , m_inputBus(AudioBus::create(numberOfInputChannels, renderBufferSize)) | |
57 , m_renderBus(AudioBus::create(numberOfOutputChannels, renderBufferSize, fal
se)) | |
58 , m_sampleRate(sampleRate) | |
59 , m_isPlaying(false) | |
60 { | |
61 // Use the optimal buffer size recommended by the audio backend. | |
62 m_callbackBufferSize = blink::Platform::current()->audioHardwareBufferSize()
; | |
63 | |
64 #if OS(ANDROID) | |
65 // The optimum low-latency hardware buffer size is usually too small on Andr
oid for WebAudio to | |
66 // render without glitching. So, if it is small, use a larger size. If it wa
s already large, use | |
67 // the requested size. | |
68 // | |
69 // Since WebAudio renders in 128-frame blocks, the small buffer sizes (144 f
or a Galaxy Nexus), | |
70 // cause significant processing jitter. Sometimes multiple blocks will proce
ssed, but other | |
71 // times will not be since the FIFO can satisfy the request. By using a larg
er | |
72 // callbackBufferSize, we smooth out the jitter. | |
73 const size_t kSmallBufferSize = 1024; | |
74 const size_t kDefaultCallbackBufferSize = 2048; | |
75 | |
76 if (m_callbackBufferSize <= kSmallBufferSize) | |
77 m_callbackBufferSize = kDefaultCallbackBufferSize; | |
78 #endif | |
79 | |
80 // Quick exit if the requested size is too large. | |
81 ASSERT(m_callbackBufferSize + renderBufferSize <= fifoSize); | |
82 if (m_callbackBufferSize + renderBufferSize > fifoSize) | |
83 return; | |
84 | |
85 m_audioDevice = adoptPtr(blink::Platform::current()->createAudioDevice(m_cal
lbackBufferSize, numberOfInputChannels, numberOfOutputChannels, sampleRate, this
, inputDeviceId)); | |
86 ASSERT(m_audioDevice); | |
87 | |
88 // Create a FIFO to handle the possibility of the callback size | |
89 // not being a multiple of the render size. If the FIFO already | |
90 // contains enough data, the data will be provided directly. | |
91 // Otherwise, the FIFO will call the provider enough times to | |
92 // satisfy the request for data. | |
93 m_fifo = adoptPtr(new AudioPullFIFO(*this, numberOfOutputChannels, fifoSize,
renderBufferSize)); | |
94 | |
95 // Input buffering. | |
96 m_inputFifo = adoptPtr(new AudioFIFO(numberOfInputChannels, fifoSize)); | |
97 | |
98 // If the callback size does not match the render size, then we need to buff
er some | |
99 // extra silence for the input. Otherwise, we can over-consume the input FIF
O. | |
100 if (m_callbackBufferSize != renderBufferSize) { | |
101 // FIXME: handle multi-channel input and don't hard-code to stereo. | |
102 RefPtr<AudioBus> silence = AudioBus::create(2, renderBufferSize); | |
103 m_inputFifo->push(silence.get()); | |
104 } | |
105 } | |
106 | |
107 AudioDestinationChromium::~AudioDestinationChromium() | |
108 { | |
109 stop(); | |
110 } | |
111 | |
112 void AudioDestinationChromium::start() | |
113 { | |
114 if (!m_isPlaying && m_audioDevice) { | |
115 m_audioDevice->start(); | |
116 m_isPlaying = true; | |
117 } | |
118 } | |
119 | |
120 void AudioDestinationChromium::stop() | |
121 { | |
122 if (m_isPlaying && m_audioDevice) { | |
123 m_audioDevice->stop(); | |
124 m_isPlaying = false; | |
125 } | |
126 } | |
127 | |
128 float AudioDestination::hardwareSampleRate() | |
129 { | |
130 return static_cast<float>(blink::Platform::current()->audioHardwareSampleRat
e()); | |
131 } | |
132 | |
133 unsigned long AudioDestination::maxChannelCount() | |
134 { | |
135 return static_cast<float>(blink::Platform::current()->audioHardwareOutputCha
nnels()); | |
136 } | |
137 | |
138 void AudioDestinationChromium::render(const blink::WebVector<float*>& sourceData
, const blink::WebVector<float*>& audioData, size_t numberOfFrames) | |
139 { | |
140 bool isNumberOfChannelsGood = audioData.size() == m_numberOfOutputChannels; | |
141 if (!isNumberOfChannelsGood) { | |
142 ASSERT_NOT_REACHED(); | |
143 return; | |
144 } | |
145 | |
146 bool isBufferSizeGood = numberOfFrames == m_callbackBufferSize; | |
147 if (!isBufferSizeGood) { | |
148 ASSERT_NOT_REACHED(); | |
149 return; | |
150 } | |
151 | |
152 // Buffer optional live input. | |
153 if (sourceData.size() >= 2) { | |
154 // FIXME: handle multi-channel input and don't hard-code to stereo. | |
155 RefPtr<AudioBus> wrapperBus = AudioBus::create(2, numberOfFrames, false)
; | |
156 wrapperBus->setChannelMemory(0, sourceData[0], numberOfFrames); | |
157 wrapperBus->setChannelMemory(1, sourceData[1], numberOfFrames); | |
158 m_inputFifo->push(wrapperBus.get()); | |
159 } | |
160 | |
161 for (unsigned i = 0; i < m_numberOfOutputChannels; ++i) | |
162 m_renderBus->setChannelMemory(i, audioData[i], numberOfFrames); | |
163 | |
164 m_fifo->consume(m_renderBus.get(), numberOfFrames); | |
165 } | |
166 | |
167 void AudioDestinationChromium::provideInput(AudioBus* bus, size_t framesToProces
s) | |
168 { | |
169 AudioBus* sourceBus = 0; | |
170 if (m_inputFifo->framesInFifo() >= framesToProcess) { | |
171 m_inputFifo->consume(m_inputBus.get(), framesToProcess); | |
172 sourceBus = m_inputBus.get(); | |
173 } | |
174 | |
175 m_callback.render(sourceBus, bus, framesToProcess); | |
176 } | |
177 | |
178 } // namespace WebCore | |
179 | |
180 #endif // ENABLE(WEB_AUDIO) | |
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