utils.h Example File

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#ifndef UTILS_H
#define UTILS_H
#include <QtCore/qglobal.h>
#include <QDebug>
QT_FORWARD_DECLARE_CLASS(QAudioFormat)
//-----------------------------------------------------------------------------
// Miscellaneous utility functions
//-----------------------------------------------------------------------------
qint64 audioDuration(const QAudioFormat &format, qint64 bytes);
qint64 audioLength(const QAudioFormat &format, qint64 microSeconds);
QString formatToString(const QAudioFormat &format);
qreal nyquistFrequency(const QAudioFormat &format);
// Scale PCM value to [-1.0, 1.0]
qreal pcmToReal(qint16 pcm);
// Scale real value in [-1.0, 1.0] to PCM
qint16 realToPcm(qreal real);
// Check whether the audio format is PCM
bool isPCM(const QAudioFormat &format);
// Check whether the audio format is signed, little-endian, 16-bit PCM
bool isPCMS16LE(const QAudioFormat &format);
// Compile-time calculation of powers of two
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; };
//-----------------------------------------------------------------------------
// Debug output
//-----------------------------------------------------------------------------
class NullDebug
{
public:
    template <typename T>
    NullDebug& operator<<(const T&) { return *this; }
};
inline NullDebug nullDebug() { return NullDebug(); }
#ifdef LOG_ENGINE
#   define ENGINE_DEBUG qDebug()
#else
#   define ENGINE_DEBUG nullDebug()
#endif
#ifdef LOG_SPECTRUMANALYSER
#   define SPECTRUMANALYSER_DEBUG qDebug()
#else
#   define SPECTRUMANALYSER_DEBUG nullDebug()
#endif
#ifdef LOG_WAVEFORM
#   define WAVEFORM_DEBUG qDebug()
#else
#   define WAVEFORM_DEBUG nullDebug()
#endif
#endif // UTILS_H