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#include <stdlib.h>
#include <stdint.h>
#include <cairo.h>
#include <gtk/gtk.h>
#include <gdk/gdkpixbuf.h>
#include "fft.h"
#include "image.h"
static void
image_fft (complex_image_t *image)
{
fft_shift_2d (image->red, image->width);
fft_shift_2d (image->green, image->width);
fft_shift_2d (image->blue, image->width);
}
static void
image_ifft (complex_image_t *image)
{
ifft_shift_2d (image->red, image->width);
ifft_shift_2d (image->green, image->width);
ifft_shift_2d (image->blue, image->width);
}
static complex_t
filter (complex_t c, double dist)
{
double m = complex_mag (c);
double arg = complex_arg (c);
return complex_from_mag_arg (m * (1/(pow (sqrt (dist) / 16, 4) + 1)) , arg);
}
static void
low_pass (complex_image_t *image, double d)
{
int w = image->width;
int h = image->height;
int i, j;
double d2 = d * d;
int c = h / 2;
for (i = 0; i < h; ++i)
{
for (j = 0; j < w; ++j)
{
int idx = i * w + j;
double dist = (c - i) * (c - i) + (c - j) * (c -j);
double t;
if (dist > 2)
{
image->red[idx] = filter (image->red[idx], dist);
image->green[idx] = filter (image->green[idx], dist);
image->blue[idx] = filter (image->blue[idx], dist);
}
else
{
image->red[idx].re = image->red[idx].im = 0;
image->green[idx].re = image->green[idx].im = 0;
image->blue[idx].re = image->blue[idx].im = 0;
}
}
}
}
static void
make_noise (complex_image_t *image)
{
int i, j;
int h, w;
h = image->height;
w = image->width;
for (i = 0; i < h; ++i)
{
for (j = 0; j < w; ++j)
{
int idx = i * w + j;
double n = 0.5 * (drand48() + drand48());
image->red[idx].re = n;
image->green[idx].re = n;
image->blue[idx].re = n;
}
}
}
int
main (int argc, char **argv)
{
char *input, *output;
GdkPixbuf *pb;
complex_image_t *image;
complex_image_t *low_passed;
g_type_init ();
image = complex_image_new (32, 32);
make_noise (image);
complex_image_show ("test", image, CONVERT_RE);
image_fft (image);
low_passed = complex_image_copy (image);
low_pass (low_passed, 2 * image->width);
complex_image_show ("low passed", low_passed, CONVERT_MAG);
complex_image_subtract (image, low_passed);
complex_image_show ("ssubtracted", image, CONVERT_MAG);
image_ifft (image);
complex_image_show ("test", image, CONVERT_RE);
return 0;
}
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