AudioRealFFT.h

#pragma once
 
#include "AudioFFT.h"
#include "FFT/FFTReal.h"
 
namespace audio_tools {
 
class FFTDriverRealFFT : public FFTDriver {
    public:
        bool begin(int len) override {
            this->len = len;
            if (p_fft_object==nullptr) p_fft_object = new ffft::FFTReal<float>(len);
            if (p_x==nullptr) p_x = new float[len];
            if (p_f==nullptr) p_f = new float[len];
            assert(p_fft_object!=nullptr);
            assert(p_x!=nullptr);
            assert(p_f!=nullptr);
            return p_fft_object!=nullptr && p_x!=nullptr && p_f!=nullptr;
        }
        void end()override{
            if (p_fft_object!=nullptr) delete p_fft_object;
            if (p_x!=nullptr) delete[] p_x;
            if (p_f!=nullptr) delete[] p_f;
            p_fft_object = nullptr;
            p_x = nullptr;
            p_f = nullptr;
        }
        void setValue(int idx, int value) override{
            p_x[idx] = value; 
        }
 
        void fft() override{
            memset(p_f,0,len*sizeof(float));
            p_fft_object->do_fft(p_f, p_x);    
        };
 
        float magnitude(int idx) override {
            return sqrt(p_x[idx] * p_x[idx] + p_f[idx] * p_f[idx]);
        }
 
        float magnitudeFast(int idx) override {
            return (p_x[idx] * p_x[idx] + p_f[idx] * p_f[idx]);
        }
 
        virtual bool isValid() override{ return p_fft_object!=nullptr; }
 
        ffft::FFTReal <float> *p_fft_object=nullptr;
        float *p_x = nullptr; // real
        float *p_f = nullptr; // complex
        int len;
 
};
 
class AudioRealFFT : public AudioFFTBase {
    public:
        AudioRealFFT():AudioFFTBase(new FFTDriverRealFFT()) {}
 
        float* realArray() {
            return driverEx()->p_x;
        }
 
        float *imgArray() {
            return driverEx()->p_f;
        }
 
        float* ifft(float *real, float* complex){
           // update mirrored values
           int len = length();
           static_cast<FFTDriverRealFFT*>(driver())->p_fft_object->do_ifft(real, complex);
           return real;
        }
 
        FFTDriverRealFFT* driverEx() {
            return (FFTDriverRealFFT*)driver();
        }
};
 
}