/*
* Copyright (C) 2011, Google Inc. All rights reserved.
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#ifndef WaveShaperDSPKernel_h
#define WaveShaperDSPKernel_h
#include "platform/audio/AudioArray.h"
#include "platform/audio/AudioDSPKernel.h"
#include "platform/audio/DownSampler.h"
#include "platform/audio/UpSampler.h"
#include "modules/webaudio/WaveShaperProcessor.h"
#include "wtf/OwnPtr.h"
namespace WebCore {
class WaveShaperProcessor;
// WaveShaperDSPKernel is an AudioDSPKernel and is responsible for non-linear distortion on one channel.
class WaveShaperDSPKernel FINAL : public AudioDSPKernel {
public:
explicit WaveShaperDSPKernel(WaveShaperProcessor*);
// AudioDSPKernel
virtual void process(const float* source, float* dest, size_t framesToProcess) OVERRIDE;
virtual void reset() OVERRIDE;
virtual double tailTime() const OVERRIDE { return 0; }
virtual double latencyTime() const OVERRIDE;
// Oversampling requires more resources, so let's only allocate them if needed.
void lazyInitializeOversampling();
protected:
// Apply the shaping curve.
void processCurve(const float* source, float* dest, size_t framesToProcess);
// Use up-sampling, process at the higher sample-rate, then down-sample.
void processCurve2x(const float* source, float* dest, size_t framesToProcess);
void processCurve4x(const float* source, float* dest, size_t framesToProcess);
WaveShaperProcessor* waveShaperProcessor() { return static_cast<WaveShaperProcessor*>(processor()); }
// Oversampling.
OwnPtr<AudioFloatArray> m_tempBuffer;
OwnPtr<AudioFloatArray> m_tempBuffer2;
OwnPtr<UpSampler> m_upSampler;
OwnPtr<DownSampler> m_downSampler;
OwnPtr<UpSampler> m_upSampler2;
OwnPtr<DownSampler> m_downSampler2;
};
} // namespace WebCore
#endif // WaveShaperDSPKernel_h