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/* $Id$ */
/*-
* Copyright (c) 2003-2004 Benedikt Meurer <benny@xfce.org>
* All rights reserved.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2, or (at your option)
* any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
* MA 02110-1301 USA.
*/
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#include <stdio.h>
#ifdef HAVE_STDLIB_H
#include <stdlib.h>
#endif
#include <limits.h>
#include <errno.h>
#include <gtk/gtk.h>
static GdkPixbuf*
create_slide (GdkPixbuf *base, int steps)
{
GdkPixbuf *result;
int rw, rh;
int bw, bh;
int i;
guchar *pixels, *p;
int rowstride;
int n_channels;
int x, y;
bw = gdk_pixbuf_get_width (base);
bh = gdk_pixbuf_get_height (base);
rw = bw * steps;
rh = bh;
result = gdk_pixbuf_new (GDK_COLORSPACE_RGB, TRUE, 8, rw, rh);
rowstride = gdk_pixbuf_get_rowstride (result);
pixels = gdk_pixbuf_get_pixels (result);
n_channels = gdk_pixbuf_get_n_channels (result);
for (i = 0; i < steps; ++i)
{
gdk_pixbuf_copy_area (base, 0, 0, bw, bh,
result, i * bw, 0);
for (x = 0; x < bw; ++x)
{
for (y = 0; y < bh; ++y)
{
p = pixels + y * rowstride + (i * bw + x) * n_channels;
p[3] = ((i + 1) * p[3]) / (steps + 1);
}
}
}
return result;
}
int main (int argc, char **argv)
{
GdkPixbuf *base;
GdkPixbuf *result;
glong val;
gtk_init (&argc, &argv);
if (argc != 3)
{
fprintf (stderr, "Usage: generate <file> <steps>\n");
return EXIT_FAILURE;
}
base = gdk_pixbuf_new_from_file (argv[1], NULL);
if (base == NULL)
{
fprintf (stderr, "generate: Unable to open file %s\n", argv[1]);
return EXIT_FAILURE;
}
val = strtol (argv[2], NULL, 10);
/* Error checking for untrusted input */
if ((errno == ERANGE && (val == LONG_MAX || val == LONG_MIN)) || (errno != 0 && val == 0))
{
perror("strtol");
exit(EXIT_FAILURE);
}
/* Sanity checks */
if (val > INT_MAX)
val = INT_MAX;
if (val < 0)
val = 0;
result = create_slide (base, val);
gdk_pixbuf_save (result, "slide.png", "png", NULL, NULL);
printf ("generate: New slide written to slide.png successfully.\n");
return EXIT_SUCCESS;
}
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