#ifndef KISS_FTR_H#define KISS_FTR_H#include "kiss_fft.h"#ifdef __cplusplusextern "C" {#endif    /*   Real optimized version can save about 45% cpu time vs. complex fft of a real seq.   */typedef struct kiss_fftr_state *kiss_fftr_cfg;kiss_fftr_cfg kiss_fftr_alloc(int nfft,int inverse_fft,void * mem, size_t * lenmem);/* nfft must be even If you don't care to allocate space, use mem = lenmem = NULL */void kiss_fftr(kiss_fftr_cfg cfg,const kiss_fft_scalar *timedata,kiss_fft_cpx *freqdata);/* input timedata has nfft scalar points output freqdata has nfft/2+1 complex points*/void kiss_fftri(kiss_fftr_cfg cfg,const kiss_fft_cpx *freqdata,kiss_fft_scalar *timedata);/* input freqdata has  nfft/2+1 complex points output timedata has nfft scalar points*/#define kiss_fftr_free free#ifdef __cplusplus}#endif#endif