Utils.h

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#ifndef UTILS_H
#define UTILS_H

#include <fftreal_wrapper.h>
//-----------------------------------------------------------------------------
// Miscellaneous utility functions
//-----------------------------------------------------------------------------

// 将pcm数据缩放到 [-1.0, 1.0]
qreal pcmToReal(qint16 pcm);

// 把 [-1.0, 1.0] 的数据转变为 PCM
qint16 realToPcm(qreal real);


template<int N> class PowerOfTwo
{ public: static const int Result = PowerOfTwo<N-1>::Result * 2; };

template<> class PowerOfTwo<0>
{ public: static const int Result = 1; };

const int    SpectrumLengthSamples  = PowerOfTwo<FFTLengthPowerOfTwo>::Result;


// 钂欐贩鍥犲瓙
const qreal SpectrumAnalyserMultiplier = 0.15;

enum WindowFunction {
    NoWindow,
    GuassWindow,
    HannWindow,
    HammingWindow,
    BartlettWindow,
    TriangleWindow,
    BlackmanWindow,
    NuttallWindow,
    SinWindow
};

const WindowFunction DefaultWindowFunction = GuassWindow;

#endif // UTILS_H