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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"
typedef enum
{
CONVERT_MAG, /* display the log magnitude */
CONVERT_RE, /* display the real value */
} convert_type_t;
typedef uint8_t (* converter_t) (complex_t c);
static uint8_t
convert_mag (complex_t d)
{
double m = complex_mag (d);
m = log (m + 1) / 12.0;
if (m > 1.0)
{
printf ("%f\n", m);
m = 1.0;
}
if (m < 0)
{
printf ("%f\n", m);
m = 0;
}
return (uint8_t) (m * 255.0 + 0.5);
}
static uint8_t
convert_re (complex_t c)
{
if (c.re > 1.0)
c.re = 1.0;
if (c.re < 0)
c.re = 0;
return c.re * 255.0 + 0.5;
}
static GdkPixbuf *
pixbuf_from_complex_image (complex_image_t *image, convert_type_t convert)
{
int w = image->width;
int h = image->height;
GdkPixbuf *pixbuf = gdk_pixbuf_new (GDK_COLORSPACE_RGB, TRUE, 8, w, h);
uint8_t *p_bits = (uint8_t *)gdk_pixbuf_get_pixels (pixbuf);
int s = gdk_pixbuf_get_rowstride (pixbuf);
converter_t converter;
int i, j;
switch (convert)
{
case CONVERT_MAG: converter = convert_mag; break;
case CONVERT_RE: converter = convert_re; break;
default:
g_assert_not_reached();
}
for (i = 0; i < h; ++i)
{
for (j = 0; j < w; ++j)
{
uint8_t *p = &(p_bits[i * s + j * 4]);
int idx = i * w + j;
p[0] = converter (image->red[idx]);
p[1] = converter (image->green[idx]);
p[2] = converter (image->blue[idx]);
p[3] = 0xff; // convert (image->alpha[idx]);
}
}
return pixbuf;
}
#define SIZE 1024
#define SIZE 1024
static gboolean
on_expose (GtkWidget *widget, GdkEventExpose *expose, gpointer data)
{
GdkPixbuf *pixbuf = data;
int i, j;
int pwidth = gdk_pixbuf_get_width (pixbuf);
int pheight = gdk_pixbuf_get_height (pixbuf);
int dwidth, dheight;
gdk_drawable_get_size (widget->window, &dwidth, &dheight);
for (i = 0; i < dheight; i += pheight)
{
for (j = 0; j < dwidth; j += pwidth)
{
gdk_draw_pixbuf (widget->window, NULL,
pixbuf, 0, 0, j, i, pwidth, pheight,
GDK_RGB_DITHER_NONE,
0, 0);
}
}
return TRUE;
}
static void
display (const char *name, complex_image_t *image, convert_type_t type)
{
GtkWidget *window, *da;
GdkPixbuf *pixbuf;
int argc;
char **argv;
char *arg0 = g_strdup (name);
argc = 1;
argv = (char **)&arg0;
gtk_init (&argc, &argv);
window = gtk_window_new (GTK_WINDOW_TOPLEVEL);
da = gtk_drawing_area_new ();
gtk_container_add (GTK_CONTAINER (window), da);
gtk_window_set_default_size (GTK_WINDOW (window), SIZE, SIZE);
pixbuf = pixbuf_from_complex_image (image, type);
g_signal_connect (da, "expose_event", G_CALLBACK (on_expose), pixbuf);
g_signal_connect (window, "delete_event", G_CALLBACK (gtk_main_quit), NULL);
gtk_widget_show_all (window);
gtk_main ();
}
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) / 16.0, 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;
image->red[idx] = filter (image->red[idx], dist);
image->green[idx] = filter (image->green[idx], dist);
image->blue[idx] = filter (image->blue[idx], dist);
}
}
}
int
main (int argc, char **argv)
{
char *input, *output;
GdkPixbuf *pb;
complex_image_t *image;
g_type_init ();
if (argc < 3)
{
printf ("Usage: %s <input name> <output name>\n\n", argv[0]);
return 1;
}
input = argv[1];
output = argv[2];
if (!(pb = gdk_pixbuf_new_from_file (input, NULL)))
{
printf ("Could not open %s\n", input);
return -1;
}
image = complex_image_from_pixbuf (pb);
g_print ("width, height %d %d\n", image->width, image->height);
image_fft (image);
display ("test", image, CONVERT_MAG);
low_pass (image, 2 * image->width);
display ("test", image, CONVERT_MAG);
image_ifft (image);
display ("test", image, CONVERT_RE);
return 0;
}
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