Source/platform/audio/AudioDSPKernelProcessor.h

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#ifndef AudioDSPKernelProcessor_h
#define AudioDSPKernelProcessor_h

#include "platform/audio/AudioBus.h"
#include "platform/audio/AudioProcessor.h"
#include "wtf/OwnPtr.h"
#include "wtf/PassOwnPtr.h"
#include "wtf/ThreadingPrimitives.h"
#include "wtf/Vector.h"

namespace WebCore {

class AudioBus;
class AudioDSPKernel;
class AudioProcessor;

// AudioDSPKernelProcessor processes one input -> one output (N channels each)
// It uses one AudioDSPKernel object per channel to do the processing, thus there is no cross-channel processing.
// Despite this limitation it turns out to be a very common and useful type of processor.

class PLATFORM_EXPORT AudioDSPKernelProcessor : public AudioProcessor {
public:
    // numberOfChannels may be later changed if object is not yet in an "initialized" state
    AudioDSPKernelProcessor(float sampleRate, unsigned numberOfChannels);

    // Subclasses create the appropriate type of processing kernel here.
    // We'll call this to create a kernel for each channel.
    virtual PassOwnPtr<AudioDSPKernel> createKernel() = 0;

    // AudioProcessor methods
    virtual void initialize();
    virtual void uninitialize();
    virtual void process(const AudioBus* source, AudioBus* destination, size_t framesToProcess);
    virtual void reset();
    virtual void setNumberOfChannels(unsigned numberOfChannels);
    virtual unsigned numberOfChannels() const { return m_numberOfChannels; }

    virtual double tailTime() const OVERRIDE;
    virtual double latencyTime() const OVERRIDE;

protected:
    Vector<OwnPtr<AudioDSPKernel> > m_kernels;
    mutable Mutex m_processLock;
    bool m_hasJustReset;
};

} // namespace WebCore

#endif // AudioDSPKernelProcessor_h