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29 #include "AudioBasicProcessorNode.h"
32 #include "AudioContext.h"
33 #include "AudioNodeInput.h"
34 #include "AudioNodeOutput.h"
35 #include "AudioProcessor.h"
39 AudioBasicProcessorNode::AudioBasicProcessorNode(AudioContext* context, double sampleRate)
40 : AudioNode(context, sampleRate)
42 addInput(adoptPtr(new AudioNodeInput(this)));
43 addOutput(adoptPtr(new AudioNodeOutput(this, 0)));
45 // The subclass must create m_processor.
48 void AudioBasicProcessorNode::initialize()
54 processor()->initialize();
56 AudioNode::initialize();
59 void AudioBasicProcessorNode::uninitialize()
65 processor()->uninitialize();
67 AudioNode::uninitialize();
70 void AudioBasicProcessorNode::process(size_t framesToProcess)
72 AudioBus* destinationBus = output(0)->bus();
74 // The realtime thread can't block on this lock, so we call tryLock() instead.
75 if (m_processLock.tryLock()) {
76 if (!isInitialized() || !processor())
77 destinationBus->zero();
79 AudioBus* sourceBus = input(0)->bus();
81 // FIXME: if we take "tail time" into account, then we can avoid calling processor()->process() once the tail dies down.
82 if (!input(0)->isConnected())
85 processor()->process(sourceBus, destinationBus, framesToProcess);
88 m_processLock.unlock();
90 // Too bad - the tryLock() failed. We must be in the middle of re-connecting and were already outputting silence anyway...
91 destinationBus->zero();
95 // Nice optimization in the very common case allowing for "in-place" processing
96 void AudioBasicProcessorNode::pullInputs(size_t framesToProcess)
98 // Render input stream - suggest to the input to render directly into output bus for in-place processing in process() if possible.
99 input(0)->pull(output(0)->bus(), framesToProcess);
102 void AudioBasicProcessorNode::reset()
105 processor()->reset();
108 // As soon as we know the channel count of our input, we can lazily initialize.
109 // Sometimes this may be called more than once with different channel counts, in which case we must safely
110 // uninitialize and then re-initialize with the new channel count.
111 void AudioBasicProcessorNode::checkNumberOfChannelsForInput(AudioNodeInput* input)
113 ASSERT(context()->isAudioThread() && context()->isGraphOwner());
115 ASSERT(input == this->input(0));
116 if (input != this->input(0))
123 unsigned numberOfChannels = input->numberOfChannels();
125 if (isInitialized() && numberOfChannels != output(0)->numberOfChannels()) {
126 // We're already initialized but the channel count has changed.
127 // We need to be careful since we may be actively processing right now, so synchronize with process().
128 MutexLocker locker(m_processLock);
132 if (!isInitialized()) {
133 // This will propagate the channel count to any nodes connected further down the chain...
134 output(0)->setNumberOfChannels(numberOfChannels);
136 // Re-initialize the processor with the new channel count.
137 processor()->setNumberOfChannels(numberOfChannels);
142 unsigned AudioBasicProcessorNode::numberOfChannels()
144 return output(0)->numberOfChannels();
147 } // namespace WebCore
149 #endif // ENABLE(WEB_AUDIO)