test/png-flatten.c

   1 /*
   2  * Copyright © 2005 Red Hat, Inc.
   3  *
   4  * Permission to use, copy, modify, distribute, and sell this software
   5  * and its documentation for any purpose is hereby granted without
   6  * fee, provided that the above copyright notice appear in all copies
   7  * and that both that copyright notice and this permission notice
   8  * appear in supporting documentation, and that the name of
   9  * Red Hat, Inc. not be used in advertising or publicity pertaining to
  10  * distribution of the software without specific, written prior
  11  * permission. Red Hat, Inc. makes no representations about the
  12  * suitability of this software for any purpose.  It is provided "as
  13  * is" without express or implied warranty.
  14  *
  15  * RED HAT, INC. DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS
  16  * SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND
  17  * FITNESS, IN NO EVENT SHALL RED HAT, INC. BE LIABLE FOR ANY SPECIAL,
  18  * INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER
  19  * RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
  20  * OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR
  21  * IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  22  *
  23  * Author: Carl Worth <cworth@cworth.org>
  24  */
  25
  26 #include <stdio.h>
  27
  28 #include <cairo.h>
  29
  30 int
  31 main (int argc, char *argv[])
  32 {
  33     cairo_t *cr;
  34     cairo_surface_t *argb, *rgb24;
  35     cairo_status_t status;
  36     const char *input, *output;
  37
  38     if (argc != 3) {
  39         fprintf (stderr, "usage: %s input.png output.png", argv[0]);
  40         fprintf (stderr, "Loads a PNG image (potentially with alpha) and writes out a flattened (no alpha)\nPNG image by first blending over white.\n");
  41         return 1;
  42     }
  43
  44     input = argv[1];
  45     output = argv[2];
  46
  47     argb = cairo_image_surface_create_from_png (input);
  48     status = cairo_surface_status (argb);
  49     if (status) {
  50         fprintf (stderr, "%s: Error: Failed to load %s: %s\n",
  51                  argv[0], input, cairo_status_to_string (status));
  52         return 1;
  53     }
  54
  55     rgb24 = cairo_image_surface_create (CAIRO_FORMAT_RGB24,
  56                                         cairo_image_surface_get_width (argb),
  57                                         cairo_image_surface_get_height (argb));
  58
  59     cr = cairo_create (rgb24);
  60
  61     cairo_set_source_rgb (cr, 1.0, 1.0, 1.0); /* white */
  62     cairo_paint (cr);
  63
  64     cairo_set_source_surface (cr, argb, 0, 0);
  65     cairo_paint (cr);
  66
  67     cairo_destroy (cr);
  68
  69     status = cairo_surface_write_to_png (rgb24, output);
  70     if (status) {
  71         fprintf (stderr, "%s: Error: Failed to write %s: %s\n",
  72                  argv[0], output, cairo_status_to_string (status));
  73         return 1;
  74     }
  75
  76     return 0;
  77 }