fft.c File Reference

#include <stdio.h>
#include <stdlib.h>
#include <math.h>
#include "fft.h"

Macros
#define	SINE(x)   (fft->SineTable[(x)])
#define	COSINE(x)   (fft->CosineTable[(x)])
#define	WINDOW(x)   (fft->WinTable[(x)])
#define	PERMUTE(x, y)   reverse((x), (y))
#define	SAMPLES   (1 << bits)
#define	REAL(x)   wave[(x)].re
#define	IMAG(x)   wave[(x)].im
#define	ALPHA   0.54

Functions
static unsigned int	reverse (unsigned int val, int bits)
void	fft_compute (fft_t *fft, complex_t wave[])
fft_t *	fft_new (int bits)
void	fft_dispose (fft_t *fft)
void	fft_window (fft_t *fft, complex_t wave[])
double	fft_amp (int n, complex_t wave[], int bits)
double	fft_amp2 (fft_t *fft, int n, complex_t wave[])
void	fft_scale (complex_t wave[], int bits)

Macro Definition Documentation

ALPHA

#define ALPHA   0.54

COSINE

#define COSINE

(

x

)

(fft->CosineTable[(x)])

IMAG

#define IMAG

(

x

)

wave[(x)].im

PERMUTE

#define PERMUTE	(		x,
			y
	)		reverse((x), (y))

REAL

#define REAL

(

x

)

wave[(x)].re

SAMPLES

#define SAMPLES   (1 << bits)

SINE

#define SINE

(

x

)

(fft->SineTable[(x)])

WINDOW

#define WINDOW

(

x

)

(fft->WinTable[(x)])

Function Documentation

fft_amp()

double fft_amp	(	int	n,
		complex_t	wave[],
		int	bits
	)

References bits, IMAG, PERMUTE, and REAL.

fft_amp2()

double fft_amp2	(	fft_t *	fft,
		int	n,
		complex_t	wave[]
	)

References fft_s::bmask, IMAG, fft_s::PermuteTable, and REAL.

Referenced by draw_fftgraph(), and draw_fftscope().

fft_compute()

void fft_compute	(	fft_t *	fft,
		complex_t	wave[]
	)

References fft_s::bits, bits, fft_s::bmask, COSINE, IMAG, fft_s::PermuteTable, REAL, SAMPLES, and SINE.

Referenced by draw_fftgraph(), and draw_fftscope().

fft_dispose()

void fft_dispose

(

fft_t *

fft

)

References fft_s::PermuteTable, and fft_s::SineTable.

Referenced by fftgraph_port_close(), and fftscope_port_close().

fft_new()

fft_t* fft_new

(

int

bits

)

References ALPHA, fft_s::bits, bits, fft_s::bmask, fft_s::CosineTable, NULL, PERMUTE, fft_s::PermuteTable, SAMPLES, fft_s::SineTable, and fft_s::WinTable.

Referenced by fftgraph_port_open(), and fftscope_port_open().

fft_scale()

void fft_scale	(	complex_t	wave[],
		int	bits
	)

References bits, complex_s::im, and complex_s::re.

Referenced by draw_fftgraph(), and draw_fftscope().

fft_window()

void fft_window	(	fft_t *	fft,
		complex_t	wave[]
	)

References fft_s::bits, bits, IMAG, REAL, SAMPLES, and WINDOW.

Referenced by draw_fftgraph(), and draw_fftscope().

reverse()

static unsigned int reverse ( unsigned int  val, int  bits  )

inlinestatic

References bits.