1 /* 2 * Copyright (c) 2003-2004, Mark Borgerding. All rights reserved. 3 * This file is part of KISS FFT - https://github.com/mborgerding/kissfft 4 * 5 * SPDX-License-Identifier: BSD-3-Clause 6 * See COPYING file for more information. 7 */ 8 9 #ifndef KISS_FTR_H 10 #define KISS_FTR_H 11 12 #include "kiss_fft.h" 13 #ifdef __cplusplus 14 extern "C" { 15 #endif 16 17 18 /* 19 20 Real optimized version can save about 45% cpu time vs. complex fft of a real seq. 21 22 23 24 */ 25 26 typedef struct kiss_fftr_state *kiss_fftr_cfg; 27 28 29 kiss_fftr_cfg kiss_fftr_alloc(int nfft,int inverse_fft,void * mem, size_t * lenmem); 30 /* 31 nfft must be even 32 33 If you don't care to allocate space, use mem = lenmem = NULL 34 */ 35 36 37 void kiss_fftr(kiss_fftr_cfg cfg,const kiss_fft_scalar *timedata,kiss_fft_cpx *freqdata); 38 /* 39 input timedata has nfft scalar points 40 output freqdata has nfft/2+1 complex points 41 */ 42 43 void kiss_fftri(kiss_fftr_cfg cfg,const kiss_fft_cpx *freqdata,kiss_fft_scalar *timedata); 44 /* 45 input freqdata has nfft/2+1 complex points 46 output timedata has nfft scalar points 47 */ 48 49 #define kiss_fftr_free KISS_FFT_FREE 50 51 #ifdef __cplusplus 52 } 53 #endif 54 #endif 55