noise

4 files changed, 133 insertions, 1 deletions

diff --git a/Makefile b/Makefile
index 519e05d..b91a5c2 100644
--- a/Makefile
+++ b/Makefile
@@ -1,7 +1,8 @@
 CFLAGS=-Wall
 LDFLAGS=-Wall -lm 
+GTKFLAGS=`pkg-config --cflags --libs gtk+-2.0`
 
-all: filters fft-test
+all: filters fft-test bluenoise
 
 filters: fft.c fft.h filters.c
 	$(CC) -o filters fft.c filters.c $(LDFLAGS)
@@ -9,3 +10,5 @@ filters: fft.c fft.h filters.c
 fft-test: fft.c fft.h fft-test.c
 	$(CC) -o fft-test fft.c fft-test.c $(LDFLAGS)
 
+bluenoise: fft.c fft.h bluenoise.c gtk-utils.c
+	$(CC) $(GTKFLAGS) -o bluenoise fft.c bluenoise.c gtk-utils.c $(LDFLAGS)
diff --git a/bluenoise.c b/bluenoise.c
new file mode 100644
index 0000000..ed57192
--- /dev/null
+++ b/bluenoise.c
@@ -0,0 +1,45 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <math.h>
+
+#include "fft.h"
+
+#define N_SAMPLES 512
+
+#define K   ((2 * M_PI) / N_SAMPLES)
+
+static double
+ssin (double f)
+{
+    return 0.5 * (sin (K * f) + 1.0);
+}
+
+static double
+scos (double f)
+{
+    return 0.5 * (cos (K * f) + 1.0);
+}
+
+int
+main ()
+{
+    complex_t *noise = malloc (sizeof (complex_t) * N_SAMPLES * N_SAMPLES);
+    int i, j;
+
+    for (i = 0; i < N_SAMPLES; ++i)
+    {
+	for (j = 0; j < N_SAMPLES; ++j)
+	{
+	    noise[i * N_SAMPLES + j].re = drand48();
+	    noise[i * N_SAMPLES + j].im = 0;
+	}
+    }
+
+    fft_2d (noise, N_SAMPLES);
+
+    shift_2d (noise, N_SAMPLES);
+
+    show_image (noise, N_SAMPLES);
+    
+    return 0;
+}
diff --git a/fft.h b/fft.h
index f98e059..d82a992 100644
--- a/fft.h
+++ b/fft.h
@@ -1,3 +1,5 @@
+#include <math.h>
+
 #ifndef FALSE
 #define FALSE (0)
 #endif
@@ -78,3 +80,6 @@ shift (complex_t *buffer, int n);
 
 void
 shift_2d (complex_t *buffer, int n);
+
+void
+show_image (complex_t *image, int n);
diff --git a/gtk-utils.c b/gtk-utils.c
new file mode 100644
index 0000000..39f697a
--- /dev/null
+++ b/gtk-utils.c
@@ -0,0 +1,79 @@
+#include <stdint.h>
+#include <gtk/gtk.h>
+#include "fft.h"
+
+static GdkPixbuf *
+pixbuf_from_buffer (complex_t *buffer, int n)
+{
+    GdkPixbuf *pixbuf =
+	gdk_pixbuf_new (GDK_COLORSPACE_RGB, TRUE, 8, n, n);
+    guint32 *p_bits = (guint32 *)gdk_pixbuf_get_pixels (pixbuf);
+    int p_stride = gdk_pixbuf_get_rowstride (pixbuf);
+    int w, h;
+
+    for (h = 0; h < n; ++h)
+    {
+	for (w = 0; w < n; ++w)
+	{
+	    char *pb = (char *)p_bits;
+	    complex_t c = buffer[h * n + w];
+	    double v;
+
+	    pb += h * p_stride + w * 4;
+
+	    v = c.re * 255.0 + 0.5;
+	    if (v > 255.0)
+		v = 255.0;
+	    if (v < 0)
+		v = 0;
+	    
+	    pb[0] = pb[1] = pb[2] = (int)v;
+	    pb[3] = 0xff;
+	}
+    }
+
+    return pixbuf;
+}
+
+static gboolean
+on_expose (GtkWidget *widget, GdkEventExpose *expose, gpointer data)
+{
+    GdkPixbuf *pixbuf = data;
+    
+    gdk_draw_pixbuf (widget->window, NULL,
+		     pixbuf, 0, 0, 0, 0,
+		     gdk_pixbuf_get_width (pixbuf),
+		     gdk_pixbuf_get_height (pixbuf),
+		     GDK_RGB_DITHER_NONE,
+		     0, 0);
+    
+    return TRUE;
+}
+
+void
+show_image (complex_t *image, int n)
+{
+    GtkWidget *window;
+    GdkPixbuf *pixbuf;
+    int argc;
+    char **argv;
+    char *arg0 = g_strdup ("pixman-test-program");
+
+    argc = 1;
+    argv = (char **)&arg0;
+
+    gtk_init (&argc, &argv);
+    
+    window = gtk_window_new (GTK_WINDOW_TOPLEVEL);
+
+    gtk_window_set_default_size (GTK_WINDOW (window), n, n);
+
+    pixbuf = pixbuf_from_buffer (image, n);
+    
+    g_signal_connect (window, "expose_event", G_CALLBACK (on_expose), pixbuf);
+    g_signal_connect (window, "delete_event", G_CALLBACK (gtk_main_quit), NULL);
+    
+    gtk_widget_show (window);
+    
+    gtk_main ();
+}