1 #ifndef KISS_FFT_S32_H 2 #define KISS_FFT_S32_H 3 4 #ifdef HAVE_CONFIG_H 5 #include "config.h" 6 #endif 7 8 #ifdef HAVE_STDINT_H 9 #include <stdint.h> 10 #endif 11 12 #include <stdlib.h> 13 #include <stdio.h> 14 #include <math.h> 15 #include <string.h> 16 #include <glib.h> 17 18 #ifdef __cplusplus 19 extern "C" { 20 #endif 21 22 /* 23 ATTENTION! 24 If you would like a : 25 -- a utility that will handle the caching of fft objects 26 -- real-only (no imaginary time component ) FFT 27 -- a multi-dimensional FFT 28 -- a command-line utility to perform ffts 29 -- a command-line utility to perform fast-convolution filtering 30 31 Then see kfc.h kiss_fftr.h kiss_fftnd.h fftutil.c kiss_fastfir.c 32 in the tools/ directory. 33 */ 34 35 #define KISS_FFT_S32_MALLOC g_malloc 36 37 #define kiss_fft_s32_scalar int32_t 38 39 typedef struct { 40 kiss_fft_s32_scalar r; 41 kiss_fft_s32_scalar i; 42 }kiss_fft_s32_cpx; 43 44 typedef struct kiss_fft_s32_state* kiss_fft_s32_cfg; 45 46 /* 47 * kiss_fft_s32_alloc 48 * 49 * Initialize a FFT (or IFFT) algorithm's cfg/state buffer. 50 * 51 * typical usage: kiss_fft_s32_cfg mycfg=kiss_fft_s32_alloc(1024,0,NULL,NULL); 52 * 53 * The return value from fft_alloc is a cfg buffer used internally 54 * by the fft routine or NULL. 55 * 56 * If lenmem is NULL, then kiss_fft_s32_alloc will allocate a cfg buffer using malloc. 57 * The returned value should be free()d when done to avoid memory leaks. 58 * 59 * The state can be placed in a user supplied buffer 'mem': 60 * If lenmem is not NULL and mem is not NULL and *lenmem is large enough, 61 * then the function places the cfg in mem and the size used in *lenmem 62 * and returns mem. 63 * 64 * If lenmem is not NULL and ( mem is NULL or *lenmem is not large enough), 65 * then the function returns NULL and places the minimum cfg 66 * buffer size in *lenmem. 67 * */ 68 69 kiss_fft_s32_cfg kiss_fft_s32_alloc(int nfft,int inverse_fft,void * mem,size_t * lenmem); 70 71 /* 72 * kiss_fft(cfg,in_out_buf) 73 * 74 * Perform an FFT on a complex input buffer. 75 * for a forward FFT, 76 * fin should be f[0] , f[1] , ... ,f[nfft-1] 77 * fout will be F[0] , F[1] , ... ,F[nfft-1] 78 * Note that each element is complex and can be accessed like 79 f[k].r and f[k].i 80 * */ 81 void kiss_fft_s32(kiss_fft_s32_cfg cfg,const kiss_fft_s32_cpx *fin,kiss_fft_s32_cpx *fout); 82 83 /* 84 A more generic version of the above function. It reads its input from every Nth sample. 85 * */ 86 void kiss_fft_s32_stride(kiss_fft_s32_cfg cfg,const kiss_fft_s32_cpx *fin,kiss_fft_s32_cpx *fout,int fin_stride); 87 88 /* If kiss_fft_s32_alloc allocated a buffer, it is one contiguous 89 buffer and can be simply free()d when no longer needed*/ 90 #define kiss_fft_s32_free g_free 91 92 /* 93 Cleans up some memory that gets managed internally. Not necessary to call, but it might clean up 94 your compiler output to call this before you exit. 95 */ 96 void kiss_fft_s32_cleanup(void); 97 98 99 /* 100 * Returns the smallest integer k, such that k>=n and k has only "fast" factors (2,3,5) 101 */ 102 int kiss_fft_s32_next_fast_size(int n); 103 104 /* for real ffts, we need an even size */ 105 #define kiss_fftr_next_fast_size_real(n) \ 106 (kiss_fft_next_fast_size( ((n)+1)>>1)<<1) 107 108 #ifdef __cplusplus 109 } 110 #endif 111 112 #endif 113