third_party/WebKit/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/ThreadingPrimitives.h"
#include "wtf/Vector.h"
#include <memory>

namespace blink {

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 std::unique_ptr<AudioDSPKernel> createKernel() = 0;

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

    double tailTime() const override;
    double latencyTime() const override;

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

} // namespace blink

#endif // AudioDSPKernelProcessor_h