gimp/plug-ins/common/color_enhance.c

291 lines
6.8 KiB
C

/* Color Enhance 0.10 --- image filter plug-in for GIMP
*
* Copyright (C) 1999 Martin Weber
* Copyright (C) 1996 Federico Mena Quintero
*
* You can contact me at martweb@gmx.net
* You can contact the original GIMP authors at gimp@xcf.berkeley.edu
*
* 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 <libgimp/gimp.h>
#include "libgimp/stdplugins-intl.h"
#define PLUG_IN_PROC "plug-in-color-enhance"
/* Declare local functions.
*/
static void query (void);
static void run (const gchar *name,
gint nparams,
const GimpParam *param,
gint *nreturn_vals,
GimpParam **return_vals);
static void Color_Enhance (GimpDrawable *drawable);
static void indexed_Color_Enhance (gint32 image_ID);
const GimpPlugInInfo PLUG_IN_INFO =
{
NULL, /* init_proc */
NULL, /* quit_proc */
query, /* query_proc */
run, /* run_proc */
};
MAIN ()
static void
query (void)
{
static const GimpParamDef args[] =
{
{ GIMP_PDB_INT32, "run-mode", "Interactive, non-interactive" },
{ GIMP_PDB_IMAGE, "image", "Input image" },
{ GIMP_PDB_DRAWABLE, "drawable", "Input drawable" }
};
gimp_install_procedure (PLUG_IN_PROC,
N_("Stretch color saturation to cover maximum possible range"),
"This simple plug-in does an automatic saturation "
"stretch. For each channel in the image, it finds "
"the minimum and maximum values... it uses those "
"values to stretch the individual histograms to the "
"full range. For some images it may do just what "
"you want; for others it may not work that well. "
"This version differs from Contrast Autostretch in "
"that it works in HSV space, and preserves hue.",
"Martin Weber",
"Martin Weber",
"1997",
N_("_Color Enhance"),
"RGB*, INDEXED*",
GIMP_PLUGIN,
G_N_ELEMENTS (args), 0,
args, NULL);
gimp_plugin_menu_register (PLUG_IN_PROC, "<Image>/Colors/Auto");
}
static void
run (const gchar *name,
gint nparams,
const GimpParam *param,
gint *nreturn_vals,
GimpParam **return_vals)
{
static GimpParam values[1];
GimpDrawable *drawable;
GimpPDBStatusType status = GIMP_PDB_SUCCESS;
GimpRunMode run_mode;
gint32 image_ID;
INIT_I18N();
run_mode = param[0].data.d_int32;
/* Get the specified drawable */
drawable = gimp_drawable_get (param[2].data.d_drawable);
image_ID = param[1].data.d_image;
/* Make sure that the drawable is gray or RGB color */
if (gimp_drawable_is_rgb (drawable->drawable_id) ||
gimp_drawable_is_gray (drawable->drawable_id))
{
gimp_progress_init (_("Color Enhance"));
gimp_tile_cache_ntiles (2 * (drawable->width / gimp_tile_width () + 1));
Color_Enhance (drawable);
if (run_mode != GIMP_RUN_NONINTERACTIVE)
gimp_displays_flush ();
}
else if (gimp_drawable_is_indexed (drawable->drawable_id))
{
indexed_Color_Enhance (image_ID);
if (run_mode != GIMP_RUN_NONINTERACTIVE)
gimp_displays_flush ();
}
else
{
status = GIMP_PDB_EXECUTION_ERROR;
}
*nreturn_vals = 1;
*return_vals = values;
values[0].type = GIMP_PDB_STATUS;
values[0].data.d_status = status;
gimp_drawable_detach (drawable);
}
static gdouble
get_v (const guchar *src)
{
gdouble h, z, v;
gint c, m, y;
gint k;
guchar map[3];
c = 255 - src[0];
m = 255 - src[1];
y = 255 - src[2];
k = c;
if (m < k) k = m;
if (y < k) k = y;
map[0] = c - k;
map[1] = m - k;
map[2] = y - k;
gimp_rgb_to_hsv4(map, &h, &z, &v);
return v;
}
static void
enhance_it (const guchar *src, guchar *dest, gdouble vlo, gdouble vhi)
{
gdouble h, z, v;
gint c, m, y;
gint k;
guchar map[3];
c = 255 - src[0];
m = 255 - src[1];
y = 255 - src[2];
k = c;
if (m < k) k = m;
if (y < k) k = y;
map[0] = c - k;
map[1] = m - k;
map[2] = y - k;
gimp_rgb_to_hsv4 (map, &h, &z, &v);
if (vhi != vlo)
v = (v - vlo) / (vhi - vlo);
gimp_hsv_to_rgb4 (map, h, z, v);
c = map[0];
m = map[1];
y = map[2];
c += k;
if (c > 255) c = 255;
m += k;
if (m > 255) m = 255;
y += k;
if (y > 255) y = 255;
dest[0] = 255 - c;
dest[1] = 255 - m;
dest[2] = 255 - y;
}
static void
indexed_Color_Enhance (gint32 image_ID)
{
guchar *cmap;
gint ncols,i;
gdouble vhi = 0.0, vlo = 1.0;
cmap = gimp_image_get_colormap (image_ID, &ncols);
if (!cmap)
{
g_message ("colormap was NULL! Quitting.");
gimp_quit();
}
for (i = 0; i < ncols; i++)
{
gdouble v = get_v (&cmap[3 * i]);
if (v > vhi) vhi = v;
if (v < vlo) vlo = v;
}
for (i = 0; i < ncols; i++)
{
enhance_it (&cmap[3 * i], &cmap[3 * i], vlo, vhi);
}
gimp_image_set_colormap (image_ID, cmap, ncols);
}
typedef struct
{
gdouble vhi;
gdouble vlo;
gboolean has_alpha;
} ColorEnhanceParam_t;
static void
find_vhi_vlo (const guchar *src,
gint bpp,
gpointer data)
{
ColorEnhanceParam_t *param = (ColorEnhanceParam_t*) data;
if (!param->has_alpha || src[3])
{
gdouble v = get_v (src);
if (v > param->vhi) param->vhi = v;
if (v < param->vlo) param->vlo = v;
}
}
static void
color_enhance_func (const guchar *src,
guchar *dest,
gint bpp,
gpointer data)
{
ColorEnhanceParam_t *param = (ColorEnhanceParam_t*) data;
enhance_it (src, dest, param->vlo, param->vhi);
if (param->has_alpha)
dest[3] = src[3];
}
static void
Color_Enhance (GimpDrawable *drawable)
{
ColorEnhanceParam_t param;
param.has_alpha = gimp_drawable_has_alpha (drawable->drawable_id);
param.vhi = 0.0;
param.vlo = 1.0;
gimp_rgn_iterate1 (drawable, 0 /* unused */, find_vhi_vlo, &param);
gimp_rgn_iterate2 (drawable, 0 /* unused */, color_enhance_func, &param);
}