demos/c_simple/gaussian_noise.c

   1 /*****************************************************************************
   2  * This file is part of gfxprim library.                                     *
   3  *                                                                           *
   4  * Gfxprim is free software; you can redistribute it and/or                  *
   5  * modify it under the terms of the GNU Lesser General Public                *
   6  * License as published by the Free Software Foundation; either              *
   7  * version 2.1 of the License, or (at your option) any later version.        *
   8  *                                                                           *
   9  * Gfxprim is distributed in the hope that it will be useful,                *
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of            *
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU         *
  12  * Lesser General Public License for more details.                           *
  13  *                                                                           *
  14  * You should have received a copy of the GNU Lesser General Public          *
  15  * License along with gfxprim; if not, write to the Free Software            *
  16  * Foundation, Inc., 51 Franklin Street, Fifth Floor,                        *
  17  * Boston, MA  02110-1301  USA                                               *
  18  *                                                                           *
  19  * Copyright (C) 2009-2013 Cyril Hrubis <metan@ucw.cz>                       *
  20  *                                                                           *
  21  *****************************************************************************/
  22
  23  /*
  24
  25    Gaussian additive noise example.
  26
  27   */
  28
  29 #include <stdio.h>
  30 #include <unistd.h>
  31 #include <string.h>
  32 #include <errno.h>
  33
  34 #include <GP.h>
  35
  36 static void help(const char *app)
  37 {
  38         printf("usage: %s -s float -m float input.img output.img\n\n", app);
  39         printf("     -s [0,1] sigma in pixels\n");
  40         printf("     -m [0,1] mu in pixels\n");
  41 }
  42
  43 int main(int argc, char *argv[])
  44 {
  45         GP_Pixmap *img;
  46         float sigma = 0.1, mu = 0.1;
  47         int opt;
  48
  49         while ((opt = getopt(argc, argv, "s:m:")) != -1) {
  50                 switch (opt) {
  51                 case 's':
  52                         sigma = atof(optarg);
  53                 break;
  54                 case 'm':
  55                         mu = atof(optarg);
  56                 break;
  57                 default:
  58                         help(argv[0]);
  59                         return 1;
  60                 }
  61         }
  62
  63         if (argc - optind != 2) {
  64                 help(argv[0]);
  65                 return 1;
  66         }
  67
  68         img = GP_LoadImage(argv[optind], NULL);
  69
  70         if (img == NULL) {
  71                 fprintf(stderr, "Failed to load image '%s': %s\n",
  72                         argv[optind], strerror(errno));
  73                 return 1;
  74         }
  75
  76         GP_Pixmap *res = GP_FilterGaussianNoiseAddAlloc(img, sigma, mu, NULL);
  77
  78         if (GP_SaveImage(res, argv[optind + 1], NULL)) {
  79                 fprintf(stderr, "Failed to save image '%s': %s",
  80                         argv[optind + 1], strerror(errno));
  81                 return 1;
  82         }
  83
  84         return 0;
  85 }