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| author | Perberos <[email protected]> | 2011-12-01 23:52:01 -0300 |
|---|---|---|
| committer | Perberos <[email protected]> | 2011-12-01 23:52:01 -0300 |
| commit | 28a029a4990d2a84f9d6a0b890eba812ea503998 (patch) | |
| tree | 7a69477d0dd6bf351801fa9698d95224e4fe47b6 /src/tools/marco-grayscale.c | |
| download | marco-28a029a4990d2a84f9d6a0b890eba812ea503998.tar.bz2 marco-28a029a4990d2a84f9d6a0b890eba812ea503998.tar.xz | |
moving from https://github.com/perberos/mate-desktop-environment
Diffstat (limited to 'src/tools/marco-grayscale.c')
| -rw-r--r-- | src/tools/marco-grayscale.c | 109 |
1 files changed, 109 insertions, 0 deletions
diff --git a/src/tools/marco-grayscale.c b/src/tools/marco-grayscale.c new file mode 100644 index 00000000..8d0cd68c --- /dev/null +++ b/src/tools/marco-grayscale.c @@ -0,0 +1,109 @@ +/* Hack for grayscaling an image */ + +/* + * Copyright (C) 2002 Red Hat Inc. + * + * 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 of the + * License, 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., 59 Temple Place - Suite 330, Boston, MA + * 02111-1307, USA. + */ + +#include <gdk-pixbuf/gdk-pixbuf.h> +#include <unistd.h> +#include <stdlib.h> +#include <math.h> + +#define INTENSITY(r, g, b) ((r) * 0.30 + (g) * 0.59 + (b) * 0.11) + +static GdkPixbuf* +grayscale_pixbuf (GdkPixbuf *pixbuf) +{ + GdkPixbuf *gray; + guchar *pixels; + int rowstride; + int pixstride; + int row; + int n_rows; + int width; + + gray = gdk_pixbuf_copy (pixbuf); + rowstride = gdk_pixbuf_get_rowstride (gray); + pixstride = gdk_pixbuf_get_has_alpha (gray) ? 4 : 3; + + pixels = gdk_pixbuf_get_pixels (gray); + n_rows = gdk_pixbuf_get_height (gray); + width = gdk_pixbuf_get_width (gray); + + row = 0; + while (row < n_rows) + { + guchar *p = pixels + row * rowstride; + guchar *end = p + (pixstride * width); + + while (p != end) + { + double v = INTENSITY (p[0], p[1], p[2]); + + p[0] = (guchar) v; + p[1] = (guchar) v; + p[2] = (guchar) v; + + p += pixstride; + } + + ++row; + } + + return gray; +} + +int +main (int argc, char **argv) +{ + GdkPixbuf *pixbuf; + GdkPixbuf *gray; + GError *err; + + if (argc != 2) + { + g_printerr ("specify a single image on the command line\n"); + return 1; + } + + g_type_init (); + + err = NULL; + pixbuf = gdk_pixbuf_new_from_file (argv[1], &err); + if (err != NULL) + { + g_printerr ("failed to load image: %s\n", err->message); + g_error_free (err); + return 1; + } + + gray = grayscale_pixbuf (pixbuf); + + err = NULL; + gdk_pixbuf_save (gray, "grayscale.png", "png", &err, NULL); + if (err != NULL) + { + g_printerr ("failed to save image: %s\n", err->message); + g_error_free (err); + return 1; + } + + g_print ("wrote grayscale.png\n"); + + return 0; +} |