| #ifndef KISS_FFT_S16_H |
| #define KISS_FFT_S16_H |
| |
| #ifdef HAVE_CONFIG_H |
| #include "config.h" |
| #endif |
| |
| #ifdef HAVE_STDINT_H |
| #include <stdint.h> |
| #endif |
| |
| #include <stdlib.h> |
| #include <stdio.h> |
| #include <math.h> |
| #include <string.h> |
| #include <glib.h> |
| |
| #ifdef __cplusplus |
| extern "C" { |
| #endif |
| |
| /* |
| ATTENTION! |
| If you would like a : |
| -- a utility that will handle the caching of fft objects |
| -- real-only (no imaginary time component ) FFT |
| -- a multi-dimensional FFT |
| -- a command-line utility to perform ffts |
| -- a command-line utility to perform fast-convolution filtering |
| |
| Then see kfc.h kiss_fftr.h kiss_fftnd.h fftutil.c kiss_fastfir.c |
| in the tools/ directory. |
| */ |
| |
| #define KISS_FFT_S16_MALLOC g_malloc |
| |
| #define kiss_fft_s16_scalar int16_t |
| |
| typedef struct { |
| kiss_fft_s16_scalar r; |
| kiss_fft_s16_scalar i; |
| }kiss_fft_s16_cpx; |
| |
| typedef struct kiss_fft_s16_state* kiss_fft_s16_cfg; |
| |
| /* |
| * kiss_fft_s16_alloc |
| * |
| * Initialize a FFT (or IFFT) algorithm's cfg/state buffer. |
| * |
| * typical usage: kiss_fft_s16_cfg mycfg=kiss_fft_s16_alloc(1024,0,NULL,NULL); |
| * |
| * The return value from fft_alloc is a cfg buffer used internally |
| * by the fft routine or NULL. |
| * |
| * If lenmem is NULL, then kiss_fft_s16_alloc will allocate a cfg buffer using malloc. |
| * The returned value should be free()d when done to avoid memory leaks. |
| * |
| * The state can be placed in a user supplied buffer 'mem': |
| * If lenmem is not NULL and mem is not NULL and *lenmem is large enough, |
| * then the function places the cfg in mem and the size used in *lenmem |
| * and returns mem. |
| * |
| * If lenmem is not NULL and ( mem is NULL or *lenmem is not large enough), |
| * then the function returns NULL and places the minimum cfg |
| * buffer size in *lenmem. |
| * */ |
| |
| kiss_fft_s16_cfg kiss_fft_s16_alloc(int nfft,int inverse_fft,void * mem,size_t * lenmem); |
| |
| /* |
| * kiss_fft(cfg,in_out_buf) |
| * |
| * Perform an FFT on a complex input buffer. |
| * for a forward FFT, |
| * fin should be f[0] , f[1] , ... ,f[nfft-1] |
| * fout will be F[0] , F[1] , ... ,F[nfft-1] |
| * Note that each element is complex and can be accessed like |
| f[k].r and f[k].i |
| * */ |
| void kiss_fft_s16(kiss_fft_s16_cfg cfg,const kiss_fft_s16_cpx *fin,kiss_fft_s16_cpx *fout); |
| |
| /* |
| A more generic version of the above function. It reads its input from every Nth sample. |
| * */ |
| void kiss_fft_s16_stride(kiss_fft_s16_cfg cfg,const kiss_fft_s16_cpx *fin,kiss_fft_s16_cpx *fout,int fin_stride); |
| |
| /* If kiss_fft_s16_alloc allocated a buffer, it is one contiguous |
| buffer and can be simply free()d when no longer needed*/ |
| #define kiss_fft_s16_free g_free |
| |
| /* |
| Cleans up some memory that gets managed internally. Not necessary to call, but it might clean up |
| your compiler output to call this before you exit. |
| */ |
| void kiss_fft_s16_cleanup(void); |
| |
| |
| /* |
| * Returns the smallest integer k, such that k>=n and k has only "fast" factors (2,3,5) |
| */ |
| int kiss_fft_s16_next_fast_size(int n); |
| |
| /* for real ffts, we need an even size */ |
| #define kiss_fftr_next_fast_size_real(n) \ |
| (kiss_fft_next_fast_size( ((n)+1)>>1)<<1) |
| |
| #ifdef __cplusplus |
| } |
| #endif |
| |
| #endif |