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 * 1. Redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution.
12 *
13 * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS'' AND ANY
14 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
15 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
16 * DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS BE LIABLE FOR ANY
17 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
18 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
19 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
20 * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
21 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
22 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
23 */
24
25 #include "config.h"
26
27 #if ENABLE(WEB_AUDIO)
28
29 #include "modules/webaudio/AudioBasicProcessorNode.h"
30
31 #include "platform/audio/AudioBus.h"
32 #include "platform/audio/AudioProcessor.h"
33 #include "modules/webaudio/AudioContext.h"
34 #include "modules/webaudio/AudioNodeInput.h"
35 #include "modules/webaudio/AudioNodeOutput.h"
36
37 namespace WebCore {
38
AudioBasicProcessorNode(AudioContext * context,float sampleRate)39 AudioBasicProcessorNode::AudioBasicProcessorNode(AudioContext* context, float sampleRate)
40 : AudioNode(context, sampleRate)
41 {
42 addInput(adoptPtr(new AudioNodeInput(this)));
43 addOutput(adoptPtr(new AudioNodeOutput(this, 1)));
44
45 // The subclass must create m_processor.
46 }
47
initialize()48 void AudioBasicProcessorNode::initialize()
49 {
50 if (isInitialized())
51 return;
52
53 ASSERT(processor());
54 processor()->initialize();
55
56 AudioNode::initialize();
57 }
58
uninitialize()59 void AudioBasicProcessorNode::uninitialize()
60 {
61 if (!isInitialized())
62 return;
63
64 ASSERT(processor());
65 processor()->uninitialize();
66
67 AudioNode::uninitialize();
68 }
69
process(size_t framesToProcess)70 void AudioBasicProcessorNode::process(size_t framesToProcess)
71 {
72 AudioBus* destinationBus = output(0)->bus();
73
74 if (!isInitialized() || !processor() || processor()->numberOfChannels() != numberOfChannels())
75 destinationBus->zero();
76 else {
77 AudioBus* sourceBus = input(0)->bus();
78
79 // FIXME: if we take "tail time" into account, then we can avoid calling processor()->process() once the tail dies down.
80 if (!input(0)->isConnected())
81 sourceBus->zero();
82
83 processor()->process(sourceBus, destinationBus, framesToProcess);
84 }
85 }
86
87 // Nice optimization in the very common case allowing for "in-place" processing
pullInputs(size_t framesToProcess)88 void AudioBasicProcessorNode::pullInputs(size_t framesToProcess)
89 {
90 // Render input stream - suggest to the input to render directly into output bus for in-place processing in process() if possible.
91 input(0)->pull(output(0)->bus(), framesToProcess);
92 }
93
94 // As soon as we know the channel count of our input, we can lazily initialize.
95 // Sometimes this may be called more than once with different channel counts, in which case we must safely
96 // uninitialize and then re-initialize with the new channel count.
checkNumberOfChannelsForInput(AudioNodeInput * input)97 void AudioBasicProcessorNode::checkNumberOfChannelsForInput(AudioNodeInput* input)
98 {
99 ASSERT(context()->isAudioThread() && context()->isGraphOwner());
100
101 ASSERT(input == this->input(0));
102 if (input != this->input(0))
103 return;
104
105 ASSERT(processor());
106 if (!processor())
107 return;
108
109 unsigned numberOfChannels = input->numberOfChannels();
110
111 if (isInitialized() && numberOfChannels != output(0)->numberOfChannels()) {
112 // We're already initialized but the channel count has changed.
113 uninitialize();
114 }
115
116 if (!isInitialized()) {
117 // This will propagate the channel count to any nodes connected further down the chain...
118 output(0)->setNumberOfChannels(numberOfChannels);
119
120 // Re-initialize the processor with the new channel count.
121 processor()->setNumberOfChannels(numberOfChannels);
122 initialize();
123 }
124
125 AudioNode::checkNumberOfChannelsForInput(input);
126 }
127
numberOfChannels()128 unsigned AudioBasicProcessorNode::numberOfChannels()
129 {
130 return output(0)->numberOfChannels();
131 }
132
tailTime() const133 double AudioBasicProcessorNode::tailTime() const
134 {
135 return m_processor->tailTime();
136 }
137
latencyTime() const138 double AudioBasicProcessorNode::latencyTime() const
139 {
140 return m_processor->latencyTime();
141 }
142
143 } // namespace WebCore
144
145 #endif // ENABLE(WEB_AUDIO)
146