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25 #ifndef AudioDestinationNode_h
26 #define AudioDestinationNode_h
28 #include "platform/audio/AudioBus.h"
29 #include "platform/audio/AudioIOCallback.h"
30 #include "platform/audio/AudioSourceProvider.h"
31 #include "modules/webaudio/AudioBuffer.h"
32 #include "modules/webaudio/AudioNode.h"
39 class AudioDestinationNode : public AudioNode, public AudioIOCallback {
41 AudioDestinationNode(AudioContext*, float sampleRate);
42 virtual ~AudioDestinationNode();
45 virtual void dispose() OVERRIDE;
46 virtual void process(size_t) OVERRIDE FINAL { } // we're pulled by hardware so this is never called
48 // The audio hardware calls render() to get the next render quantum of audio into destinationBus.
49 // It will optionally give us local/live audio input in sourceBus (if it's not 0).
50 virtual void render(AudioBus* sourceBus, AudioBus* destinationBus, size_t numberOfFrames) OVERRIDE FINAL;
52 size_t currentSampleFrame() const { return m_currentSampleFrame; }
53 double currentTime() const { return currentSampleFrame() / static_cast<double>(sampleRate()); }
55 virtual unsigned long maxChannelCount() const { return 0; }
57 virtual void startRendering() = 0;
60 // LocalAudioInputProvider allows us to expose an AudioSourceProvider for local/live audio input.
61 // If there is local/live audio input, we call set() with the audio input data every render quantum.
62 class LocalAudioInputProvider FINAL : public AudioSourceProvider {
64 LocalAudioInputProvider()
65 : m_sourceBus(AudioBus::create(2, AudioNode::ProcessingSizeInFrames)) // FIXME: handle non-stereo local input.
69 void set(AudioBus* bus)
72 m_sourceBus->copyFrom(*bus);
75 // AudioSourceProvider.
76 virtual void provideInput(AudioBus* destinationBus, size_t numberOfFrames) OVERRIDE
78 bool isGood = destinationBus && destinationBus->length() == numberOfFrames && m_sourceBus->length() == numberOfFrames;
81 destinationBus->copyFrom(*m_sourceBus);
85 RefPtr<AudioBus> m_sourceBus;
88 virtual double tailTime() const OVERRIDE FINAL { return 0; }
89 virtual double latencyTime() const OVERRIDE FINAL { return 0; }
91 // Counts the number of sample-frames processed by the destination.
92 size_t m_currentSampleFrame;
94 LocalAudioInputProvider m_localAudioInputProvider;
99 #endif // AudioDestinationNode_h