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/*
* Copyright © 2005 Red Hat, Inc.
*
* Permission to use, copy, modify, distribute, and sell this software
* and its documentation for any purpose is hereby granted without
* fee, provided that the above copyright notice appear in all copies
* and that both that copyright notice and this permission notice
* appear in supporting documentation, and that the name of
* Red Hat, Inc. not be used in advertising or publicity pertaining to
* distribution of the software without specific, written prior
* permission. Red Hat, Inc. makes no representations about the
* suitability of this software for any purpose. It is provided "as
* is" without express or implied warranty.
*
* RED HAT, INC. DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS
* SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND
* FITNESS, IN NO EVENT SHALL RED HAT, INC. BE LIABLE FOR ANY SPECIAL,
* INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER
* RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
* OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR
* IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*
* Author: Carl Worth <cworth@cworth.org>
*/
#include <stdio.h>
#include <cairo.h>
int
main (int argc, char *argv[])
{
cairo_t *cr;
cairo_surface_t *argb, *rgb24;
cairo_status_t status;
const char *input, *output;
if (argc != 3) {
fprintf (stderr, "usage: %s input.png output.png", argv[0]);
fprintf (stderr, "Loads a PNG image (potentially with alpha) and writes out a flattened (no alpha)\nPNG image by first blending over white.\n");
return 1;
}
input = argv[1];
output = argv[2];
argb = cairo_image_surface_create_from_png (input);
status = cairo_surface_status (argb);
if (status) {
fprintf (stderr, "%s: Error: Failed to load %s: %s\n",
argv[0], input, cairo_status_to_string (status));
return 1;
}
rgb24 = cairo_image_surface_create (CAIRO_FORMAT_RGB24,
cairo_image_surface_get_width (argb),
cairo_image_surface_get_height (argb));
cr = cairo_create (rgb24);
cairo_set_source_rgb (cr, 1.0, 1.0, 1.0); /* white */
cairo_paint (cr);
cairo_set_source_surface (cr, argb, 0, 0);
cairo_paint (cr);
cairo_destroy (cr);
status = cairo_surface_write_to_png (rgb24, output);
if (status) {
fprintf (stderr, "%s: Error: Failed to write %s: %s\n",
argv[0], output, cairo_status_to_string (status));
return 1;
}
return 0;
}
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