Chris@434: #ifndef KISS_FFT_H
Chris@434: #define KISS_FFT_H
Chris@434: 
Chris@434: #include <stdlib.h>
Chris@434: #include <stdio.h>
Chris@434: #include <math.h>
Chris@434: #include <string.h>
Chris@434: 
Chris@434: #ifdef __cplusplus
Chris@434: extern "C" {
Chris@434: #endif
Chris@434: 
Chris@434: /*
Chris@434:  ATTENTION!
Chris@434:  If you would like a :
Chris@434:  -- a utility that will handle the caching of fft objects
Chris@434:  -- real-only (no imaginary time component ) FFT
Chris@434:  -- a multi-dimensional FFT
Chris@434:  -- a command-line utility to perform ffts
Chris@434:  -- a command-line utility to perform fast-convolution filtering
Chris@434: 
Chris@434:  Then see kfc.h kiss_fftr.h kiss_fftnd.h fftutil.c kiss_fastfir.c
Chris@434:   in the tools/ directory.
Chris@434: */
Chris@434: 
Chris@434: #ifdef USE_SIMD
Chris@434: # include <xmmintrin.h>
Chris@434: # define kiss_fft_scalar __m128
Chris@434: #define KISS_FFT_MALLOC(nbytes) _mm_malloc(nbytes,16)
Chris@434: #define KISS_FFT_FREE _mm_free
Chris@434: #else	
Chris@434: #define KISS_FFT_MALLOC malloc
Chris@434: #define KISS_FFT_FREE free
Chris@434: #endif	
Chris@434: 
Chris@434: 
Chris@434: #ifdef FIXED_POINT
Chris@434: #include <sys/types.h>	
Chris@434: # if (FIXED_POINT == 32)
Chris@434: #  define kiss_fft_scalar int32_t
Chris@434: # else	
Chris@434: #  define kiss_fft_scalar int16_t
Chris@434: # endif
Chris@434: #else
Chris@434: # ifndef kiss_fft_scalar
Chris@434: /*  default is float */
Chris@434: #   define kiss_fft_scalar float
Chris@434: # endif
Chris@434: #endif
Chris@434: 
Chris@434: typedef struct {
Chris@434:     kiss_fft_scalar r;
Chris@434:     kiss_fft_scalar i;
Chris@434: }kiss_fft_cpx;
Chris@434: 
Chris@434: typedef struct kiss_fft_state* kiss_fft_cfg;
Chris@434: 
Chris@434: /* 
Chris@434:  *  kiss_fft_alloc
Chris@434:  *  
Chris@434:  *  Initialize a FFT (or IFFT) algorithm's cfg/state buffer.
Chris@434:  *
Chris@434:  *  typical usage:      kiss_fft_cfg mycfg=kiss_fft_alloc(1024,0,NULL,NULL);
Chris@434:  *
Chris@434:  *  The return value from fft_alloc is a cfg buffer used internally
Chris@434:  *  by the fft routine or NULL.
Chris@434:  *
Chris@434:  *  If lenmem is NULL, then kiss_fft_alloc will allocate a cfg buffer using malloc.
Chris@434:  *  The returned value should be free()d when done to avoid memory leaks.
Chris@434:  *  
Chris@434:  *  The state can be placed in a user supplied buffer 'mem':
Chris@434:  *  If lenmem is not NULL and mem is not NULL and *lenmem is large enough,
Chris@434:  *      then the function places the cfg in mem and the size used in *lenmem
Chris@434:  *      and returns mem.
Chris@434:  *  
Chris@434:  *  If lenmem is not NULL and ( mem is NULL or *lenmem is not large enough),
Chris@434:  *      then the function returns NULL and places the minimum cfg 
Chris@434:  *      buffer size in *lenmem.
Chris@434:  * */
Chris@434: 
Chris@434: kiss_fft_cfg kiss_fft_alloc(int nfft,int inverse_fft,void * mem,size_t * lenmem); 
Chris@434: 
Chris@434: /*
Chris@434:  * kiss_fft(cfg,in_out_buf)
Chris@434:  *
Chris@434:  * Perform an FFT on a complex input buffer.
Chris@434:  * for a forward FFT,
Chris@434:  * fin should be  f[0] , f[1] , ... ,f[nfft-1]
Chris@434:  * fout will be   F[0] , F[1] , ... ,F[nfft-1]
Chris@434:  * Note that each element is complex and can be accessed like
Chris@434:     f[k].r and f[k].i
Chris@434:  * */
Chris@434: void kiss_fft(kiss_fft_cfg cfg,const kiss_fft_cpx *fin,kiss_fft_cpx *fout);
Chris@434: 
Chris@434: /*
Chris@434:  A more generic version of the above function. It reads its input from every Nth sample.
Chris@434:  * */
Chris@434: void kiss_fft_stride(kiss_fft_cfg cfg,const kiss_fft_cpx *fin,kiss_fft_cpx *fout,int fin_stride);
Chris@434: 
Chris@434: /* If kiss_fft_alloc allocated a buffer, it is one contiguous 
Chris@434:    buffer and can be simply free()d when no longer needed*/
Chris@434: #define kiss_fft_free free
Chris@434: 
Chris@434: /*
Chris@434:  Cleans up some memory that gets managed internally. Not necessary to call, but it might clean up 
Chris@434:  your compiler output to call this before you exit.
Chris@434: */
Chris@434: void kiss_fft_cleanup(void);
Chris@434: 	
Chris@434: 
Chris@434: /*
Chris@434:  * Returns the smallest integer k, such that k>=n and k has only "fast" factors (2,3,5)
Chris@434:  */
Chris@434: int kiss_fft_next_fast_size(int n);
Chris@434: 
Chris@434: /* for real ffts, we need an even size */
Chris@434: #define kiss_fftr_next_fast_size_real(n) \
Chris@434:         (kiss_fft_next_fast_size( ((n)+1)>>1)<<1)
Chris@434: 
Chris@434: #ifdef __cplusplus
Chris@434: } 
Chris@434: #endif
Chris@434: 
Chris@434: #endif