#define FFTTOOLS_H
#include <QVector>
+#include <QHash>
+#include <tools/kiss_fftr.h>
class FFTTools
{
public:
FFTTools();
+ ~FFTTools();
enum WindowType { Window_Rect, Window_Triangle, Window_Hamming };
default is 0)
* Nothing for the Hamming window
*/
- static const QVector<float> window(const WindowType windowType, const int size, const float param);
+ static const QVector<float> window(const WindowType windowType, const int size, const float param = 0);
- static const QString windowSignature(const WindowType windowType, const int size, const float param);
+ static const QString windowSignature(const WindowType windowType, const int size, const float param = 0);
+
+ /** Returns a signature for a kiss_fft configuration
+ used as a hash in the cache */
+ static const QString cfgSignature(const int size);
+
+ /** Calculates the Fourier Tranformation of the input audio frame.
+ The resulting values will be given in relative dezibel: The maximum power is 0 dB, lower powers have
+ negative dB values.
+ * audioFrame: Interleaved format with #numChannels channels
+ * freqSpectrum: Array pointer to write the data into
+ * windowSize must be divisible by 2,
+ * freqSpectrum has to be of size windowSize/2
+ For windowType and param see the FFTTools::window() function above.
+ */
+ void fftNormalized(const QVector<int16_t> audioFrame, const uint channel, const uint numChannels, float *freqSpectrum,
+ const WindowType windowType, const uint windowSize, const float param = 0);
+
+private:
+ QHash<QString, kiss_fftr_cfg> m_fftCfgs; // FFT cfg cache
+ QHash<QString, QVector<float> > m_windowFunctions; // Window function cache
};