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#ifndef ReverbConvolverStage_h
#define ReverbConvolverStage_h
#include "platform/audio/AudioArray.h"
#include "platform/audio/FFTFrame.h"
#include "wtf/Noncopyable.h"
#include "wtf/OwnPtr.h"
namespace WebCore {
class ReverbAccumulationBuffer;
class ReverbConvolver;
class FFTConvolver;
class DirectConvolver;
// A ReverbConvolverStage represents the convolution associated with a sub-section of a large impulse response.
// It incorporates a delay line to account for the offset of the sub-section within the larger impulse response.
class PLATFORM_EXPORT ReverbConvolverStage {
WTF_MAKE_NONCOPYABLE(ReverbConvolverStage);
public:
// renderPhase is useful to know so that we can manipulate the pre versus post delay so that stages will perform
// their heavy work (FFT processing) on different slices to balance the load in a real-time thread.
ReverbConvolverStage(const float* impulseResponse, size_t responseLength, size_t reverbTotalLatency, size_t stageOffset, size_t stageLength, size_t fftSize, size_t renderPhase, size_t renderSliceSize, ReverbAccumulationBuffer*, bool directMode = false);
// WARNING: framesToProcess must be such that it evenly divides the delay buffer size (stage_offset).
void process(const float* source, size_t framesToProcess);
void processInBackground(ReverbConvolver* convolver, size_t framesToProcess);
void reset();
// Useful for background processing
int inputReadIndex() const { return m_inputReadIndex; }
private:
OwnPtr<FFTFrame> m_fftKernel;
OwnPtr<FFTConvolver> m_fftConvolver;
AudioFloatArray m_preDelayBuffer;
ReverbAccumulationBuffer* m_accumulationBuffer;
int m_accumulationReadIndex;
int m_inputReadIndex;
size_t m_preDelayLength;
size_t m_postDelayLength;
size_t m_preReadWriteIndex;
size_t m_framesProcessed;
AudioFloatArray m_temporaryBuffer;
bool m_directMode;
OwnPtr<AudioFloatArray> m_directKernel;
OwnPtr<DirectConvolver> m_directConvolver;
};
} // namespace WebCore
#endif // ReverbConvolverStage_h