1 #ifndef KISS_FTR_H 2 #define KISS_FTR_H 3 4 #include "kiss_fft.h" 5 #ifdef __cplusplus 6 extern "C" { 7 #endif 8 9 10 /* 11 12 Real optimized version can save about 45% cpu time vs. complex fft of a real seq. 13 14 15 16 */ 17 18 typedef struct kiss_fftr_state *kiss_fftr_cfg; 19 20 21 kiss_fftr_cfg kiss_fftr_alloc(int nfft,int inverse_fft,void * mem, size_t * lenmem); 22 /* 23 nfft must be even 24 25 If you don't care to allocate space, use mem = lenmem = NULL 26 */ 27 28 29 void kiss_fftr(kiss_fftr_cfg cfg,const kiss_fft_scalar *timedata,kiss_fft_cpx *freqdata); 30 /* 31 input timedata has nfft scalar points 32 output freqdata has nfft/2+1 complex points 33 */ 34 35 void kiss_fftri(kiss_fftr_cfg cfg,const kiss_fft_cpx *freqdata,kiss_fft_scalar *timedata); 36 /* 37 input freqdata has nfft/2+1 complex points 38 output timedata has nfft scalar points 39 */ 40 41 #define kiss_fftr_free free 42 43 #ifdef __cplusplus 44 } 45 #endif 46 #endif 47