gimp/app/equalize.c

99 lines
2.5 KiB
C

/* The GIMP -- an image manipulation program
* Copyright (C) 1995 Spencer Kimball and Peter Mattis
*
* 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 "config.h"
#include <gtk/gtk.h>
#include "apptypes.h"
#include "drawable.h"
#include "equalize.h"
#include "gimpimage.h"
#include "gimplut.h"
#include "lut_funcs.h"
#include "gimphistogram.h"
#include "pixel_processor.h"
#include "pixel_region.h"
#include "libgimp/gimpintl.h"
void
image_equalize (GimpImage *gimage)
{
GimpDrawable *drawable;
drawable = gimp_image_active_drawable (gimage);
if (gimp_drawable_is_indexed (drawable))
{
g_message (_("Equalize does not operate on indexed drawables."));
return;
}
equalize (gimage, drawable, TRUE);
}
void
equalize (GimpImage *gimage,
GimpDrawable *drawable,
gboolean mask_only)
{
PixelRegion srcPR, destPR;
guchar *mask;
gint has_alpha;
gint alpha, bytes;
gint x1, y1, x2, y2;
GimpHistogram *hist;
GimpLut *lut;
mask = NULL;
bytes = gimp_drawable_bytes (drawable);
has_alpha = gimp_drawable_has_alpha (drawable);
alpha = has_alpha ? (bytes - 1) : bytes;
hist = gimp_histogram_new ();
gimp_histogram_calculate_drawable (hist, drawable);
/* Build equalization LUT */
lut = eq_histogram_lut_new (hist, bytes);
/* Apply the histogram */
gimp_drawable_mask_bounds (drawable, &x1, &y1, &x2, &y2);
pixel_region_init (&srcPR, gimp_drawable_data (drawable),
x1, y1, (x2 - x1), (y2 - y1), FALSE);
pixel_region_init (&destPR, gimp_drawable_shadow (drawable),
x1, y1, (x2 - x1), (y2 - y1), TRUE);
pixel_regions_process_parallel ((p_func) gimp_lut_process, lut,
2, &srcPR, &destPR);
gimp_lut_free (lut);
gimp_histogram_free (hist);
gimp_drawable_merge_shadow (drawable, TRUE);
drawable_update (drawable,
x1, y1,
(x2 - x1), (y2 - y1));
}