gimp/app/threshold.c

734 lines
18 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 <stdlib.h>
#include <string.h>
#include <math.h>
#include "appenv.h"
#include "actionarea.h"
#include "drawable.h"
#include "general.h"
#include "gdisplay.h"
#include "histogram.h"
#include "image_map.h"
#include "interface.h"
#include "threshold.h"
#define TEXT_WIDTH 45
#define HISTOGRAM_WIDTH 256
#define HISTOGRAM_HEIGHT 150
typedef struct _Threshold Threshold;
struct _Threshold
{
int x, y; /* coords for last mouse click */
};
typedef struct _ThresholdDialog ThresholdDialog;
struct _ThresholdDialog
{
GtkWidget *shell;
GtkWidget *low_threshold_text;
GtkWidget *high_threshold_text;
Histogram *histogram;
GimpDrawable *drawable;
ImageMap image_map;
int color;
int low_threshold;
int high_threshold;
gint preview;
};
/* threshold action functions */
static void threshold_button_press (Tool *, GdkEventButton *, gpointer);
static void threshold_button_release (Tool *, GdkEventButton *, gpointer);
static void threshold_motion (Tool *, GdkEventMotion *, gpointer);
static void threshold_cursor_update (Tool *, GdkEventMotion *, gpointer);
static void threshold_control (Tool *, int, gpointer);
static ThresholdDialog * threshold_new_dialog (void);
static void threshold_preview (ThresholdDialog *);
static void threshold_ok_callback (GtkWidget *, gpointer);
static void threshold_cancel_callback (GtkWidget *, gpointer);
static gint threshold_delete_callback (GtkWidget *, GdkEvent *, gpointer);
static void threshold_preview_update (GtkWidget *, gpointer);
static void threshold_low_threshold_text_update (GtkWidget *, gpointer);
static void threshold_high_threshold_text_update (GtkWidget *, gpointer);
static void *threshold_options = NULL;
static ThresholdDialog *threshold_dialog = NULL;
static void threshold (PixelRegion *, PixelRegion *, void *);
static void threshold_histogram_info (PixelRegion *, PixelRegion *, HistogramValues, void *);
static void threshold_histogram_range (int, int, HistogramValues, void *);
static Argument * threshold_invoker (Argument *);
/* threshold machinery */
static void
threshold (PixelRegion *srcPR,
PixelRegion *destPR,
void *user_data)
{
ThresholdDialog *td;
unsigned char *src, *s;
unsigned char *dest, *d;
int has_alpha, alpha;
int w, h, b;
int value;
td = (ThresholdDialog *) user_data;
h = srcPR->h;
src = srcPR->data;
dest = destPR->data;
has_alpha = (srcPR->bytes == 2 || srcPR->bytes == 4);
alpha = has_alpha ? srcPR->bytes - 1 : srcPR->bytes;
while (h--)
{
w = srcPR->w;
s = src;
d = dest;
while (w--)
{
if (td->color)
{
value = MAX (s[RED_PIX], s[GREEN_PIX]);
value = MAX (value, s[BLUE_PIX]);
value = (value >= td->low_threshold && value <= td->high_threshold ) ? 255 : 0;
}
else
value = (s[GRAY_PIX] >= td->low_threshold && s[GRAY_PIX] <= td->high_threshold) ? 255 : 0;
for (b = 0; b < alpha; b++)
d[b] = value;
if (has_alpha)
d[alpha] = s[alpha];
s += srcPR->bytes;
d += destPR->bytes;
}
src += srcPR->rowstride;
dest += destPR->rowstride;
}
}
static void
threshold_histogram_info (PixelRegion *srcPR,
PixelRegion *maskPR,
HistogramValues values,
void *user_data)
{
ThresholdDialog *td;
unsigned char *src, *s;
unsigned char *mask, *m;
int w, h;
int value;
mask = NULL;
m = NULL;
td = (ThresholdDialog *) user_data;
h = srcPR->h;
src = srcPR->data;
if (maskPR)
mask = maskPR->data;
while (h--)
{
w = srcPR->w;
s = src;
if (maskPR)
m = mask;
while (w--)
{
if (td->color)
{
value = MAX (s[RED_PIX], s[GREEN_PIX]);
value = MAX (value, s[BLUE_PIX]);
}
else
value = s[GRAY_PIX];
if (maskPR)
values[HISTOGRAM_VALUE][value] += (double) *m / 255.0;
else
values[HISTOGRAM_VALUE][value] += 1.0;
s += srcPR->bytes;
if (maskPR)
m += maskPR->bytes;
}
src += srcPR->rowstride;
if (maskPR)
mask += maskPR->rowstride;
}
}
static void
threshold_histogram_range (int start,
int end,
HistogramValues values,
void *user_data)
{
ThresholdDialog *td;
char text[12];
td = (ThresholdDialog *) user_data;
td->low_threshold = start;
td->high_threshold = end;
sprintf (text, "%d", start);
gtk_entry_set_text (GTK_ENTRY (td->low_threshold_text), text);
sprintf (text, "%d", end);
gtk_entry_set_text (GTK_ENTRY (td->high_threshold_text), text);
if (td->preview)
threshold_preview (td);
}
/* threshold action functions */
static void
threshold_button_press (Tool *tool,
GdkEventButton *bevent,
gpointer gdisp_ptr)
{
GDisplay *gdisp;
gdisp = gdisp_ptr;
tool->drawable = gimage_active_drawable (gdisp->gimage);
}
static void
threshold_button_release (Tool *tool,
GdkEventButton *bevent,
gpointer gdisp_ptr)
{
}
static void
threshold_motion (Tool *tool,
GdkEventMotion *mevent,
gpointer gdisp_ptr)
{
}
static void
threshold_cursor_update (Tool *tool,
GdkEventMotion *mevent,
gpointer gdisp_ptr)
{
GDisplay *gdisp;
gdisp = (GDisplay *) gdisp_ptr;
gdisplay_install_tool_cursor (gdisp, GDK_TOP_LEFT_ARROW);
}
static void
threshold_control (Tool *tool,
int action,
gpointer gdisp_ptr)
{
Threshold * thresh;
thresh = (Threshold *) tool->private;
switch (action)
{
case PAUSE :
break;
case RESUME :
break;
case HALT :
if (threshold_dialog)
{
active_tool->preserve = TRUE;
image_map_abort (threshold_dialog->image_map);
active_tool->preserve = FALSE;
threshold_dialog->image_map = NULL;
threshold_cancel_callback (NULL, (gpointer) threshold_dialog);
}
break;
}
}
Tool *
tools_new_threshold ()
{
Tool * tool;
Threshold * private;
/* The tool options */
if (!threshold_options)
threshold_options = tools_register_no_options (THRESHOLD, "Threshold Options");
/* The threshold dialog */
if (!threshold_dialog)
threshold_dialog = threshold_new_dialog ();
else
if (!GTK_WIDGET_VISIBLE (threshold_dialog->shell))
gtk_widget_show (threshold_dialog->shell);
tool = (Tool *) g_malloc (sizeof (Tool));
private = (Threshold *) g_malloc (sizeof (Threshold));
tool->type = THRESHOLD;
tool->state = INACTIVE;
tool->scroll_lock = 1; /* Disallow scrolling */
tool->auto_snap_to = TRUE;
tool->private = (void *) private;
tool->button_press_func = threshold_button_press;
tool->button_release_func = threshold_button_release;
tool->motion_func = threshold_motion;
tool->arrow_keys_func = standard_arrow_keys_func;
tool->cursor_update_func = threshold_cursor_update;
tool->control_func = threshold_control;
tool->preserve = FALSE;
return tool;
}
void
tools_free_threshold (Tool *tool)
{
Threshold * thresh;
thresh = (Threshold *) tool->private;
/* Close the color select dialog */
if (threshold_dialog)
threshold_cancel_callback (NULL, (gpointer) threshold_dialog);
g_free (thresh);
}
void
threshold_initialize (GDisplay *gdisp)
{
if (drawable_indexed (gimage_active_drawable (gdisp->gimage)))
{
g_message ("Threshold does not operate on indexed drawables.");
return;
}
/* The threshold dialog */
if (!threshold_dialog)
threshold_dialog = threshold_new_dialog ();
else
if (!GTK_WIDGET_VISIBLE (threshold_dialog->shell))
gtk_widget_show (threshold_dialog->shell);
threshold_dialog->drawable = gimage_active_drawable (gdisp->gimage);
threshold_dialog->color = drawable_color (threshold_dialog->drawable);
threshold_dialog->image_map = image_map_create (gdisp, threshold_dialog->drawable);
histogram_update (threshold_dialog->histogram,
threshold_dialog->drawable,
threshold_histogram_info,
(void *) threshold_dialog);
histogram_range (threshold_dialog->histogram,
threshold_dialog->low_threshold,
threshold_dialog->high_threshold);
if (threshold_dialog->preview)
threshold_preview (threshold_dialog);
}
/****************************/
/* Select by Color dialog */
/****************************/
/* the action area structure */
static ActionAreaItem action_items[] =
{
{ "OK", threshold_ok_callback, NULL, NULL },
{ "Cancel", threshold_cancel_callback, NULL, NULL }
};
static ThresholdDialog *
threshold_new_dialog ()
{
ThresholdDialog *td;
GtkWidget *vbox;
GtkWidget *hbox;
GtkWidget *label;
GtkWidget *frame;
GtkWidget *toggle;
td = g_malloc (sizeof (ThresholdDialog));
td->preview = TRUE;
td->low_threshold = 127;
td->high_threshold = 255;
/* The shell and main vbox */
td->shell = gtk_dialog_new ();
gtk_window_set_wmclass (GTK_WINDOW (td->shell), "threshold", "Gimp");
gtk_window_set_title (GTK_WINDOW (td->shell), "Threshold");
/* handle the wm close signal */
gtk_signal_connect (GTK_OBJECT (td->shell), "delete_event",
GTK_SIGNAL_FUNC (threshold_delete_callback),
td);
vbox = gtk_vbox_new (FALSE, 2);
gtk_container_border_width (GTK_CONTAINER (vbox), 2);
gtk_box_pack_start (GTK_BOX (GTK_DIALOG (td->shell)->vbox), vbox, TRUE, TRUE, 0);
/* Horizontal box for threshold text widget */
hbox = gtk_hbox_new (TRUE, 2);
gtk_box_pack_start (GTK_BOX (vbox), hbox, FALSE, FALSE, 0);
label = gtk_label_new ("Threshold Range: ");
gtk_box_pack_start (GTK_BOX (hbox), label, FALSE, FALSE, 0);
gtk_widget_show (label);
/* low threshold text */
td->low_threshold_text = gtk_entry_new ();
gtk_entry_set_text (GTK_ENTRY (td->low_threshold_text), "127");
gtk_widget_set_usize (td->low_threshold_text, TEXT_WIDTH, 25);
gtk_box_pack_start (GTK_BOX (hbox), td->low_threshold_text, FALSE, FALSE, 0);
gtk_signal_connect (GTK_OBJECT (td->low_threshold_text), "changed",
(GtkSignalFunc) threshold_low_threshold_text_update,
td);
gtk_widget_show (td->low_threshold_text);
/* high threshold text */
td->high_threshold_text = gtk_entry_new ();
gtk_entry_set_text (GTK_ENTRY (td->high_threshold_text), "255");
gtk_widget_set_usize (td->high_threshold_text, TEXT_WIDTH, 25);
gtk_box_pack_start (GTK_BOX (hbox), td->high_threshold_text, FALSE, FALSE, 0);
gtk_signal_connect (GTK_OBJECT (td->high_threshold_text), "changed",
(GtkSignalFunc) threshold_high_threshold_text_update,
td);
gtk_widget_show (td->high_threshold_text);
gtk_widget_show (hbox);
/* The threshold histogram */
hbox = gtk_hbox_new (TRUE, 2);
gtk_box_pack_start (GTK_BOX (vbox), hbox, TRUE, FALSE, 0);
frame = gtk_frame_new (NULL);
gtk_frame_set_shadow_type (GTK_FRAME (frame), GTK_SHADOW_ETCHED_IN);
gtk_box_pack_start (GTK_BOX (hbox), frame, TRUE, FALSE, 0);
td->histogram = histogram_create (HISTOGRAM_WIDTH, HISTOGRAM_HEIGHT,
threshold_histogram_range, (void *) td);
gtk_container_add (GTK_CONTAINER (frame), td->histogram->histogram_widget);
gtk_widget_show (td->histogram->histogram_widget);
gtk_widget_show (frame);
gtk_widget_show (hbox);
/* Horizontal box for preview */
hbox = gtk_hbox_new (TRUE, 2);
gtk_box_pack_start (GTK_BOX (vbox), hbox, FALSE, FALSE, 0);
/* The preview toggle */
toggle = gtk_check_button_new_with_label ("Preview");
gtk_toggle_button_set_state (GTK_TOGGLE_BUTTON (toggle), td->preview);
gtk_box_pack_start (GTK_BOX (hbox), toggle, TRUE, FALSE, 0);
gtk_signal_connect (GTK_OBJECT (toggle), "toggled",
(GtkSignalFunc) threshold_preview_update,
td);
gtk_widget_show (label);
gtk_widget_show (toggle);
gtk_widget_show (hbox);
/* The action area */
action_items[0].user_data = td;
action_items[1].user_data = td;
build_action_area (GTK_DIALOG (td->shell), action_items, 2, 0);
gtk_widget_show (vbox);
gtk_widget_show (td->shell);
/* This code is so far removed from the histogram creation because the
function histogram_range requires a non-NULL drawable, and that
doesn't happen until after the top-level dialog is shown. */
histogram_range (td->histogram, td->low_threshold, td->high_threshold);
return td;
}
static void
threshold_preview (ThresholdDialog *td)
{
if (!td->image_map)
g_message ("threshold_preview(): No image map");
image_map_apply (td->image_map, threshold, (void *) td);
}
static void
threshold_ok_callback (GtkWidget *widget,
gpointer client_data)
{
ThresholdDialog *td;
td = (ThresholdDialog *) client_data;
if (GTK_WIDGET_VISIBLE (td->shell))
gtk_widget_hide (td->shell);
active_tool->preserve = TRUE;
if (!td->preview)
image_map_apply (td->image_map, threshold, (void *) td);
if (td->image_map)
image_map_commit (td->image_map);
active_tool->preserve = FALSE;
td->image_map = NULL;
}
static gint
threshold_delete_callback (GtkWidget *w,
GdkEvent *e,
gpointer client_data)
{
threshold_cancel_callback (w, client_data);
return TRUE;
}
static void
threshold_cancel_callback (GtkWidget *widget,
gpointer client_data)
{
ThresholdDialog *td;
td = (ThresholdDialog *) client_data;
if (GTK_WIDGET_VISIBLE (td->shell))
gtk_widget_hide (td->shell);
if (td->image_map)
{
active_tool->preserve = TRUE;
image_map_abort (td->image_map);
active_tool->preserve = FALSE;
gdisplays_flush ();
}
td->image_map = NULL;
}
static void
threshold_preview_update (GtkWidget *w,
gpointer data)
{
ThresholdDialog *td;
td = (ThresholdDialog *) data;
if (GTK_TOGGLE_BUTTON (w)->active)
{
td->preview = TRUE;
threshold_preview (td);
}
else
td->preview = FALSE;
}
static void
threshold_low_threshold_text_update (GtkWidget *w,
gpointer data)
{
ThresholdDialog *td;
char *str;
int value;
td = (ThresholdDialog *) data;
str = gtk_entry_get_text (GTK_ENTRY (w));
value = BOUNDS (((int) atof (str)), 0, td->high_threshold);
if (value != td->low_threshold)
{
td->low_threshold = value;
histogram_range (td->histogram,
td->low_threshold,
td->high_threshold);
if (td->preview)
threshold_preview (td);
}
}
static void
threshold_high_threshold_text_update (GtkWidget *w,
gpointer data)
{
ThresholdDialog *td;
char *str;
int value;
td = (ThresholdDialog *) data;
str = gtk_entry_get_text (GTK_ENTRY (w));
value = BOUNDS (((int) atof (str)), td->low_threshold, 255);
if (value != td->high_threshold)
{
td->high_threshold = value;
histogram_range (td->histogram,
td->low_threshold,
td->high_threshold);
if (td->preview)
threshold_preview (td);
}
}
/* The threshold procedure definition */
ProcArg threshold_args[] =
{
{ PDB_IMAGE,
"image",
"the image"
},
{ PDB_DRAWABLE,
"drawable",
"the drawable"
},
{ PDB_INT32,
"low_threshold",
"the low threshold value: (0 <= low_threshold <= 255)"
},
{ PDB_INT32,
"high_threshold",
"the high threshold value: (0 <= high_threshold <= 255)"
}
};
ProcRecord threshold_proc =
{
"gimp_threshold",
"Threshold the specified drawable",
"This procedures generates a threshold map of the specified drawable. All pixels between the values of 'low_threshold' and 'high_threshold' are replaced with white, and all other pixels with black.",
"Spencer Kimball & Peter Mattis",
"Spencer Kimball & Peter Mattis",
"1997",
PDB_INTERNAL,
/* Input arguments */
4,
threshold_args,
/* Output arguments */
0,
NULL,
/* Exec method */
{ { threshold_invoker } },
};
static Argument *
threshold_invoker (args)
Argument *args;
{
PixelRegion srcPR, destPR;
int success = TRUE;
ThresholdDialog td;
GImage *gimage;
GimpDrawable *drawable;
int low_threshold;
int high_threshold;
int int_value;
int x1, y1, x2, y2;
void *pr;
drawable = NULL;
low_threshold = 0;
high_threshold = 0;
/* the gimage */
if (success)
{
int_value = args[0].value.pdb_int;
if (! (gimage = gimage_get_ID (int_value)))
success = FALSE;
}
/* the drawable */
if (success)
{
int_value = args[1].value.pdb_int;
drawable = drawable_get_ID (int_value);
if (drawable == NULL || gimage != drawable_gimage (drawable))
success = FALSE;
}
/* make sure the drawable is not indexed color */
if (success)
success = ! drawable_indexed (drawable);
/* low threhsold */
if (success)
{
int_value = args[2].value.pdb_int;
if (int_value >= 0 && int_value < 256)
low_threshold = int_value;
else
success = FALSE;
}
/* high threhsold */
if (success)
{
int_value = args[3].value.pdb_int;
if (int_value >= 0 && int_value < 256)
high_threshold = int_value;
else
success = FALSE;
}
if (success)
success = (low_threshold < high_threshold);
/* arrange to modify the levels */
if (success)
{
td.color = drawable_color (drawable);
td.low_threshold = low_threshold;
td.high_threshold = high_threshold;
/* The application should occur only within selection bounds */
drawable_mask_bounds (drawable, &x1, &y1, &x2, &y2);
pixel_region_init (&srcPR, drawable_data (drawable), x1, y1, (x2 - x1), (y2 - y1), FALSE);
pixel_region_init (&destPR, drawable_shadow (drawable), x1, y1, (x2 - x1), (y2 - y1), TRUE);
for (pr = pixel_regions_register (2, &srcPR, &destPR); pr != NULL; pr = pixel_regions_process (pr))
threshold (&srcPR, &destPR, (void *) &td);
drawable_merge_shadow (drawable, TRUE);
drawable_update (drawable, x1, y1, (x2 - x1), (y2 - y1));
}
return procedural_db_return_args (&threshold_proc, success);
}