Files
raDIYo/swfftcalc.h
2025-08-05 22:36:00 +02:00

93 lines
1.9 KiB
C++

/***************************************************************************
source::worx raDIYo
Copyright © 2020-2022 c.holzheuer
chris@sourceworx.org
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
***************************************************************************/
#ifndef SWFFTCALC_H
#define SWFFTCALC_H
#include <complex>
#include <iostream>
#include <valarray>
#include <QObject>
#include <QThread>
#include <QAudioFormat>
#include <QAudioProbe>
#include <QAudioDeviceInfo>
#include <QElapsedTimer>
#include <raDIYoglobals.h>
// Scale PCM value to [-1.0, 1.0]
qreal xpcmToReal(qint16 pcm);
/**
* @brief Berechnet mittels FFT ein Spectrum
* aus dem @see @QAudioBuffer. Das Spectrum wird beim
* Abspielen eines Songs angezeigt.
* @see SWSpectrumWidget
* @see SWPlayerControl
*/
class SWFFTCalc : public QObject
{
Q_OBJECT
public:
explicit SWFFTCalc( QObject* parent = nullptr );
virtual ~SWFFTCalc();
signals:
void spectrumReady( const SWValVec& spectrum );
public slots:
void onAudioProbed( const QAudioBuffer& audiobuffer );
protected:
using Complex = std::complex<double>;
using CArray = std::valarray<Complex>;
void bareFFT( CArray& x );
static constexpr const int SWNumSamples = 4096;
const double PI = 3.141592653589793238460;
// Fudge factor used to calculate the spectrum bar heights
//const qreal SpectrumAnalyserMultiplier = 0.15;
const qreal SWFudgeFactor = 0.17;
int _bufferDuration = 0;
QElapsedTimer _timer;
SWValVec _frames;
SWValVec _hannWindow;
// überdenken: geht das so schneller?
// SWValVec _logscale;
SWValVec _spectrum;
CArray _complexFrame;
};
#endif // SWFFTCALC_H