kissfft/kiss_fft.h
2003-08-09 00:59:17 +00:00

46 lines
1.0 KiB
C

#ifndef KISS_FFT_H
#define KISS_FFT_H
#ifndef kiss_fft_scalar
# ifdef FIXED_POINT
# define kiss_fft_scalar short
# else
# define kiss_fft_scalar float
# endif
#endif
typedef struct {
kiss_fft_scalar r;
kiss_fft_scalar i;
}kiss_fft_cpx;
/*
* fft_alloc
*
* Initialize a radix 2 FFT (or IFFT) algorithm.
*
* The return value from fft_alloc is a cfg buffer used internally
* by the fft routine.
*
* Call free() on it when done using it to avoid memory leaks.
* */
void* kiss_fft_alloc(int nfft,int inverse_fft);
// free() the state when done using it
/*
* kiss_fft
*
* Perform an in-place FFT on a complex input buffer.
*
* the input buffer should be real(f[0]) , imag(f[0]), ... ,real(f[nfft-1]) , imag(f[nfft-1])
* the the output will be real(F[0]) , imag(F[0]), ... ,real(F[nfft-1]) , imag(F[nfft-1])
*
* */
void kiss_fft( const void* cfg , kiss_fft_cpx *f ); // call for each buffer
// when done with the cfg for a given fft size and direction, simply free it
#define kiss_fft_free free
#endif