Source/platform/audio/MultiChannelResampler.h

/*
 * Copyright (C) 2011 Google Inc. All rights reserved.
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 *
 * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
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#ifndef MultiChannelResampler_h
#define MultiChannelResampler_h

#include "platform/audio/SincResampler.h"
#include "wtf/Noncopyable.h"
#include "wtf/OwnPtr.h"

namespace WebCore {

class AudioBus;

class PLATFORM_EXPORT MultiChannelResampler {
    WTF_MAKE_NONCOPYABLE(MultiChannelResampler);
public:
    MultiChannelResampler(double scaleFactor, unsigned numberOfChannels);

    // Process given AudioSourceProvider for streaming applications.
    void process(AudioSourceProvider*, AudioBus* destination, size_t framesToProcess);

private:
    // FIXME: the mac port can have a more highly optimized implementation based on CoreAudio
    // instead of SincResampler. For now the default implementation will be used on all ports.
    // https://bugs.webkit.org/show_bug.cgi?id=75118

    // Each channel will be resampled using a high-quality SincResampler.
    Vector<OwnPtr<SincResampler> > m_kernels;

    unsigned m_numberOfChannels;
};

} // namespace WebCore

#endif // MultiChannelResampler_h