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- /* edge filter for the GIMP
- * -Peter Mattis
- *
- * This filter performs edge detection on the input image.
- * The code for this filter is based on "pgmedge", a program
- * that is part of the netpbm package.
- */
-
- /* pgmedge.c - edge-detect a portable graymap
- **
- ** Copyright (C) 1989 by Jef Poskanzer.
- **
- ** Permission to use, copy, modify, and distribute this software and its
- ** documentation for any purpose and without fee is hereby granted, provided
- ** that the above copyright notice appear in all copies and that both that
- ** copyright notice and this permission notice appear in supporting
- ** documentation. This software is provided "as is" without express or
- ** implied warranty.
- */
-
- /*
- * Ported to GIMP Plug-in API 1.0
- * version 1.07
- * This version requires GIMP v0.99.10 or above.
- *
- * This plug-in performs edge detection. The code is based on edge.c
- * for GIMP 0.54 by Peter Mattis.
- *
- * Eiichi Takamori <taka@ma1.seikyou.ne.jp>
- * http://ha1.seikyou.ne.jp/home/taka/gimp/
- *
- * Tips: you can enter arbitrary value into entry.
- * (not bounded between 1.0 and 10.0)
- *
- * Changes from version 1.06 to version 1.07:
- * - Added entry
- * - Cleaned up code a bit
- *
- * Differences from Peter Mattis's original `edge' plug-in:
- * - Added Wrapmode. (useful for tilable images)
- * - Enhanced speed in this version.
- * - It works with the alpha channel.
- */
-
- #include "config.h"
-
- #include <stdio.h>
- #include <stdlib.h>
-
- #include <gtk/gtk.h>
-
- #include <libgimp/gimp.h>
- #include <libgimp/gimpui.h>
-
- #include "libgimp/stdplugins-intl.h"
-
-
- #ifdef RCSID
- static gchar rcsid[] = "$Id: edge.c,v 1.18 2000/08/22 01:26:54 neo Exp $";
- #endif
-
- /* Some useful macros */
-
- #define TILE_CACHE_SIZE 48
-
- enum
- {
- WRAP,
- SMEAR,
- BLACK
- };
-
- typedef struct
- {
- gdouble amount;
- gint wrapmode;
- } EdgeVals;
-
- typedef struct
- {
- gint run;
- } EdgeInterface;
-
- typedef struct
- {
- GimpTile *tile;
- gint row, col; /* tile's row, col */
- gint bpp;
- gint tile_width, tile_height;
- GimpDrawable *drawable;
- gint drawable_width, drawable_height;
- } TileBuf;
-
- /*
- * Function prototypes.
- */
-
- static void query (void);
- static void run (gchar *name,
- gint nparams,
- GimpParam *param,
- gint *nreturn_vals,
- GimpParam **return_vals);
-
- static void edge (GimpDrawable *drawable);
- static gint edge_dialog (GimpDrawable *drawable);
-
- static long long_sqrt (long n);
-
- static void init_tile_buf (TileBuf *buf,
- GimpDrawable *drawable);
- static void get_tile_pixel (TileBuf *buf,
- gint x,
- gint y,
- guchar *pixel,
- gint wrapmode);
- static void end_tile_buf (TileBuf *buf);
-
- /***** Local vars *****/
-
- GimpPlugInInfo PLUG_IN_INFO =
- {
- NULL, /* init */
- NULL, /* quit */
- query, /* query */
- run, /* run */
- };
-
- static EdgeVals evals =
- {
- 2.0, /* amount */
- SMEAR /* wrapmode */
- };
-
- static EdgeInterface eint =
- {
- FALSE /* run */
- };
-
- /***** Functions *****/
-
- MAIN ()
-
- static void
- query (void)
- {
- static GimpParamDef args[] =
- {
- { GIMP_PDB_INT32, "run_mode", "Interactive, non-interactive" },
- { GIMP_PDB_IMAGE, "image", "Input image (unused)" },
- { GIMP_PDB_DRAWABLE, "drawable", "Input drawable" },
- { GIMP_PDB_FLOAT, "amount", "Edge detection amount" },
- { GIMP_PDB_INT32, "wrapmode", "Edge detection behavior: { WRAP (0), SMEAR (1), BLACK (2) }" }
- };
- static gint nargs = sizeof (args) / sizeof (args[0]);
-
- gchar *help_string =
- "Perform edge detection on the contents of the specified drawable. It "
- "applies, I think, convolution with 3x3 kernel. AMOUNT is an arbitrary "
- "constant, WRAPMODE is like displace plug-in (useful for tilable image).";
-
- gimp_install_procedure ("plug_in_edge",
- "Perform edge detection on the contents of the specified drawable",
- help_string,
- "Peter Mattis & (ported to 1.0 by) Eiichi Takamori",
- "Peter Mattis",
- "1996",
- N_("<Image>/Filters/Edge-Detect/Edge..."),
- "RGB*, GRAY*",
- GIMP_PLUGIN,
- nargs, 0,
- args, NULL);
- }
-
- static void
- run (gchar *name,
- gint nparams,
- GimpParam *param,
- gint *nreturn_vals,
- GimpParam **return_vals)
- {
- static GimpParam values[1];
- GimpDrawable *drawable;
- GimpRunModeType run_mode;
- GimpPDBStatusType status = GIMP_PDB_SUCCESS;
-
- run_mode = param[0].data.d_int32;
-
- /* Get the specified drawable */
- drawable = gimp_drawable_get (param[2].data.d_drawable);
-
- *nreturn_vals = 1;
- *return_vals = values;
-
- values[0].type = GIMP_PDB_STATUS;
- values[0].data.d_status = status;
-
- switch (run_mode)
- {
- case GIMP_RUN_INTERACTIVE:
- INIT_I18N_UI();
- /* Possibly retrieve data */
- gimp_get_data ("plug_in_edge", &evals);
-
- /* First acquire information with a dialog */
- if (! edge_dialog (drawable))
- return;
- break;
-
- case GIMP_RUN_NONINTERACTIVE:
- /* Make sure all the arguments are there! */
- if (nparams != 5)
- status = GIMP_PDB_CALLING_ERROR;
- if (status == GIMP_PDB_SUCCESS)
- {
- evals.amount = param[3].data.d_float;
- evals.wrapmode = param[4].data.d_int32;
- }
- INIT_I18N();
- break;
-
- case GIMP_RUN_WITH_LAST_VALS:
- /* Possibly retrieve data */
- gimp_get_data ("plug_in_edge", &evals);
- INIT_I18N();
- break;
-
- default:
- break;
- }
-
- /* make sure the drawable exist and is not indexed */
- if (gimp_drawable_is_rgb (drawable->id) ||
- gimp_drawable_is_gray (drawable->id))
- {
- gimp_progress_init (_("Edge Detection..."));
-
- /* set the tile cache size */
- gimp_tile_cache_ntiles (TILE_CACHE_SIZE);
-
- /* run the edge effect */
- edge (drawable);
-
- if (run_mode != GIMP_RUN_NONINTERACTIVE)
- gimp_displays_flush ();
-
- /* Store data */
- if (run_mode == GIMP_RUN_INTERACTIVE)
- gimp_set_data ("plug_in_edge", &evals, sizeof (EdgeVals));
- }
- else
- {
- /* gimp_message ("edge: cannot operate on indexed color images"); */
- status = GIMP_PDB_EXECUTION_ERROR;
- }
-
- values[0].data.d_status = status;
-
- gimp_drawable_detach (drawable);
- }
-
- /*********************************************************************
-
- TileBuf Util Routines: Util routines for getting arbitrary pixel
- CAUTION -- the tile is read only !!
-
- **********************************************************************/
-
- static void
- init_tile_buf (TileBuf *buf,
- GimpDrawable *drawable)
- {
- buf->tile = NULL;
- buf->col = 0;
- buf->row = 0;
- if (gimp_drawable_is_rgb (drawable->id))
- buf->bpp = 3;
- else
- buf->bpp = 1;
- buf->tile_width = gimp_tile_width();
- buf->tile_height = gimp_tile_height();
- buf->drawable = drawable;
- buf->drawable_width = gimp_drawable_width(drawable->id);
- buf->drawable_height = gimp_drawable_height(drawable->id);
- }
-
- static void
- get_tile_pixel (TileBuf *buf,
- gint x,
- gint y,
- guchar *pixel,
- gint wrapmode)
- {
- gint b;
- gint offx, offy;
- gint row, col;
- guchar *ptr;
-
- if (x < 0 || x >= buf->drawable_width ||
- y < 0 || y >= buf->drawable_height)
- switch (wrapmode)
- {
- case WRAP:
- if (x < 0 || x >= buf->drawable_width)
- {
- x %= buf->drawable_width;
- if (x < 0)
- x += buf->drawable_width;
- }
- if (y < 0 || y >= buf->drawable_height)
- {
- y %= buf->drawable_height;
- if (y < 0)
- y += buf->drawable_height;
- }
- break;
- case SMEAR:
- if (x < 0)
- x = 0;
- if (x >= buf->drawable_width)
- x = buf->drawable_width - 1;
- if (y < 0)
- y = 0;
- if (y >= buf->drawable_height)
- y = buf->drawable_height - 1;
- break;
- case BLACK:
- if (x < 0 || x >= buf->drawable_width ||
- y < 0 || y >= buf->drawable_height)
- {
- for (b = 0; b < buf->bpp; b++)
- pixel[b] = 0;
- return;
- }
- break;
- default:
- return;
- }
-
- col = x / buf->tile_width;
- offx = x % buf->tile_width;
- row = y / buf->tile_height;
- offy = y % buf->tile_height;
-
- /* retrieve tile */
- if (!buf->tile || col != buf->col || row != buf->row)
- {
- if(buf->tile)
- gimp_tile_unref (buf->tile, FALSE);
- buf->col = col;
- buf->row = row;
- buf->tile = gimp_drawable_get_tile (buf->drawable, FALSE, row, col);
- gimp_tile_ref (buf->tile);
- }
-
- /* retrieve target pixel */
- ptr = buf->tile->data + (offy * buf->tile->ewidth + offx) * buf->tile->bpp;
- for(b = 0; b < buf->bpp; b++)
- pixel[b] = ptr[b];
- }
-
- static void
- end_tile_buf (TileBuf *buf)
- {
- if (buf->tile)
- gimp_tile_unref (buf->tile, FALSE);
- }
-
- /**********************************************************************
- TileBuf Util Routines End
- **********************************************************************/
-
- static long
- long_sqrt (long n)
- {
- #define lsqrt_max4pow (1UL << 30)
- /* lsqrt_max4pow is the (machine-specific) largest power of 4 that can
- * be represented in an unsigned long.
- *
- * Compute the integer square root of the integer argument n
- * Method is to divide n by x computing the quotient x and remainder r
- * Notice that the divisor x is changing as the quotient x changes
- *
- * Instead of shifting the dividend/remainder left, we shift the
- * quotient/divisor right. The binary point starts at the extreme
- * left, and shifts two bits at a time to the extreme right.
- *
- * The residue contains n-x^2. (Within these comments, the ^ operator
- * signifies exponentiation rather than exclusive or. Also, the /
- * operator returns fractions, rather than truncating, so 1/4 means
- * one fourth, not zero.)
- *
- * Since (x + 1/2)^2 == x^2 + x + 1/4,
- * n - (x + 1/2)^2 == (n - x^2) - (x + 1/4)
- * Thus, we can increase x by 1/2 if we decrease (n-x^2) by (x+1/4)
- */
-
- gulong residue; /* n - x^2 */
- gulong root; /* x + 1/4 */
- gulong half; /* 1/2 */
-
- residue = n; /* n - (x = 0)^2, with suitable alignment */
-
- /*
- * if the correct answer fits in two bits, pull it out of a magic hat
- */
- if (residue <= 12)
- return (0x03FFEA94 >> (residue *= 2)) & 3;
-
- root = lsqrt_max4pow; /* x + 1/4, shifted all the way left */
- /* half = root + root; 1/2, shifted likewise */
-
- /*
- * Unwind iterations corresponding to leading zero bits
- */
- while (root > residue)
- root >>= 2;
-
- /*
- * Unwind the iteration corresponding to the first one bit
- * Operations have been rearranged and combined for efficiency
- * Initialization of half is folded into this iteration
- */
- residue -= root; /* Decrease (n-x^2) by (0+1/4) */
- half = root >> 2; /* 1/4, with binary point shifted right 2 */
- root += half; /* x=1. (root is now (x=1)+1/4.) */
- half += half; /* 1/2, properly aligned */
-
- /*
- * Normal loop (there is at least one iteration remaining)
- */
- do
- {
- if (root <= residue) /* Whenever we can, */
- {
- residue -= root; /* decrease (n-x^2) by (x+1/4) */
- root += half; /* increase x by 1/2 */
- }
- half >>= 2; /* Shift binary point 2 places right */
- root -= half; /* x{ +1/2 } +1/4 - 1/8 == x { +1/2 } 1/8 */
- root >>= 1; /* 2x{ +1 } +1/4, shifted right 2 places */
- }
- while (half); /* When 1/2 == 0, bin. point is at far right */
-
- /*
- * round up if (x+1/2)^2 < n
- */
- if (root < residue)
- ++root;
-
- /*
- * Guaranteed to be correctly rounded (or truncated)
- */
- return root;
- }
-
- /********************************************************/
- /* Edge Detection main */
- /********************************************************/
-
- static void
- edge (GimpDrawable *drawable)
- {
- /*
- * this function is too long, so I must split this into a few
- * functions later ... -- taka
- */
- GimpPixelRgn src_rgn, dest_rgn;
- gpointer pr;
- TileBuf buf;
- guchar *srcrow, *src;
- guchar *destrow, *dest;
- guchar pix00[3], pix01[3], pix02[3];
- guchar pix10[3],/*pix11[3],*/ pix12[3];
- guchar pix20[3], pix21[3], pix22[3];
- glong width, height;
- gint alpha, has_alpha, chan;
- gint x, y;
- gint x1, y1, x2, y2;
- glong sum1, sum2;
- glong sum, scale;
- gint maxval;
- gint cur_progress;
- gint max_progress;
- gint wrapmode;
-
- if (evals.amount < 1.0)
- evals.amount = 1.0;
-
- init_tile_buf (&buf, drawable);
-
- gimp_drawable_mask_bounds (drawable->id, &x1, &y1, &x2, &y2);
-
- width = gimp_drawable_width (drawable->id);
- height = gimp_drawable_height (drawable->id);
- alpha = gimp_drawable_bpp (drawable->id);
- has_alpha = gimp_drawable_has_alpha (drawable->id);
- if (has_alpha)
- alpha--;
-
- maxval = 255;
- scale = (10 << 16) / evals.amount;
- wrapmode = evals.wrapmode;
-
- cur_progress = 0;
- max_progress = (x2 - x1) * (y2 - y1);
-
- gimp_pixel_rgn_init (&src_rgn, drawable, x1, y1, x2-x1, y2-y1, FALSE, FALSE);
- gimp_pixel_rgn_init (&dest_rgn, drawable, x1, y1, x2-x1, y2-y1, TRUE, TRUE);
-
- for (pr = gimp_pixel_rgns_register (2, &src_rgn, &dest_rgn);
- pr != NULL;
- pr = gimp_pixel_rgns_process (pr))
- {
- srcrow = src_rgn.data;
- destrow = dest_rgn.data;
- for (y = dest_rgn.y;
- y < (dest_rgn.y + dest_rgn.h);
- y++, srcrow += src_rgn.rowstride, destrow += dest_rgn.rowstride)
- {
- src = srcrow;
- dest = destrow;
- for (x = dest_rgn.x;
- x < (dest_rgn.x + dest_rgn.w);
- x++, src += src_rgn.bpp, dest += dest_rgn.bpp)
- {
- if(dest_rgn.x < x && x < dest_rgn.x + dest_rgn.w - 1 &&
- dest_rgn.y < y && y < dest_rgn.y + dest_rgn.h - 1)
- {
- /*
- ** 3x3 kernel is inside of the tile -- do fast
- ** version
- */
- for (chan = 0; chan < alpha; chan++)
- {
- /*
- * PIX(1,1) is the current pixel, so
- * e.g. PIX(0,0) means 1 above and 1 left pixel.
- *
- * There were casting to `long' in GIMP 0.54
- * edge code, but I think `guchar' should be
- * extended to `int' with minus operators, so
- * there's no need to cast to `long'. Both sum1
- * and sum2 will be between -4*255 to 4*255
- *
- * -- taka
- */
- #define PIX(X,Y) src[ (Y-1)*(int)src_rgn.rowstride + (X-1)*(int)src_rgn.bpp + chan ]
- /* make convolution */
- sum1 = (PIX(2,0) - PIX(0,0)) +
- 2 * (PIX(2,1) - PIX(0,1)) +
- (PIX(2,2) - PIX(2,0));
- sum2 = (PIX(0,2) - PIX(0,0)) +
- 2 * (PIX(1,2) - PIX(1,0)) +
- (PIX(2,2) - PIX(2,0));
- #undef PIX
- /* common job ... */
- sum = long_sqrt ((long) sum1 * sum1 + (long) sum2 * sum2);
- sum = (sum * scale) >> 16; /* arbitrary scaling factor */
- if (sum > maxval)
- sum = maxval;
- dest[chan] = sum;
- }
- }
- else
- {
- /*
- ** The kernel is not inside of the tile -- do slow
- ** version
- */
- /*
- * When the kernel intersects the boundary of the
- * image, get_tile_pixel() will (should) do the
- * right work with `wrapmode'.
- */
- get_tile_pixel (&buf, x-1, y-1, pix00, wrapmode);
- get_tile_pixel (&buf, x , y-1, pix10, wrapmode);
- get_tile_pixel (&buf, x+1, y-1, pix20, wrapmode);
- get_tile_pixel (&buf, x-1, y , pix01, wrapmode);
- get_tile_pixel (&buf, x+1, y , pix21, wrapmode);
- get_tile_pixel (&buf, x-1, y+1, pix02, wrapmode);
- get_tile_pixel (&buf, x , y+1, pix12, wrapmode);
- get_tile_pixel (&buf, x+1, y+1, pix22, wrapmode);
-
- for (chan = 0; chan < alpha; chan++)
- {
- /* make convolution */
- sum1 = (pix20[chan] - pix00[chan]) +
- 2 * (pix21[chan] - pix01[chan]) +
- (pix22[chan] - pix20[chan]);
- sum2 = (pix02[chan] - pix00[chan]) +
- 2 * (pix12[chan] - pix10[chan]) +
- (pix22[chan] - pix20[chan]);
- /* common job ... */
- sum = long_sqrt ((long) sum1 * sum1 + (long) sum2 * sum2);
- sum = (sum * scale) >> 16; /* arbitrary scaling factor */
- if (sum > maxval) sum = maxval;
- dest[chan] = sum;
- }
- }
- if (has_alpha)
- dest[alpha] = src[alpha];
- }
- }
- cur_progress += dest_rgn.w * dest_rgn.h;
- gimp_progress_update ((double) cur_progress / (double) max_progress);
- }
-
- end_tile_buf (&buf);
- gimp_drawable_flush (drawable);
- gimp_drawable_merge_shadow (drawable->id, TRUE);
- gimp_drawable_update (drawable->id, x1, y1, (x2 - x1), (y2 - y1));
- }
-
- /*******************************************************/
- /* Dialog */
- /*******************************************************/
-
- static void
- edge_ok_callback (GtkWidget *widget,
- gpointer data)
- {
- eint.run = TRUE;
-
- gtk_widget_destroy (GTK_WIDGET (data));
- }
-
- static gint
- edge_dialog (GimpDrawable *drawable)
- {
- GtkWidget *dlg;
- GtkWidget *frame;
- GtkWidget *table;
- GtkWidget *hbox;
- GtkWidget *toggle;
- GtkObject *scale_data;
- GSList *group = NULL;
-
- gint use_wrap = (evals.wrapmode == WRAP);
- gint use_smear = (evals.wrapmode == SMEAR);
- gint use_black = (evals.wrapmode == BLACK);
-
- gimp_ui_init ("edge", FALSE);
-
- dlg = gimp_dialog_new (_("Edge Detection"), "edge",
- gimp_standard_help_func, "filters/edge.html",
- GTK_WIN_POS_MOUSE,
- FALSE, TRUE, FALSE,
-
- _("OK"), edge_ok_callback,
- NULL, NULL, NULL, TRUE, FALSE,
- _("Cancel"), gtk_widget_destroy,
- NULL, 1, NULL, FALSE, TRUE,
-
- NULL);
-
- gtk_signal_connect (GTK_OBJECT (dlg), "destroy",
- GTK_SIGNAL_FUNC (gtk_main_quit),
- NULL);
-
- /* parameter settings */
- frame = gtk_frame_new (_("Parameter Settings"));
- gtk_frame_set_shadow_type (GTK_FRAME (frame), GTK_SHADOW_ETCHED_IN);
- gtk_container_set_border_width (GTK_CONTAINER (frame), 6);
- gtk_box_pack_start (GTK_BOX (GTK_DIALOG (dlg)->vbox), frame, TRUE, TRUE, 0);
-
- table = gtk_table_new (2, 3, FALSE);
- gtk_table_set_col_spacings (GTK_TABLE (table), 4);
- gtk_table_set_row_spacings (GTK_TABLE (table), 4);
- gtk_container_set_border_width (GTK_CONTAINER (table), 4);
- gtk_container_add (GTK_CONTAINER (frame), table);
-
- /* Label, scale, entry for evals.amount */
- scale_data = gimp_scale_entry_new (GTK_TABLE (table), 0, 0,
- _("Amount:"), 100, 0,
- evals.amount, 1.0, 10.0, 0.1, 1.0, 1,
- TRUE, 0, 0,
- NULL, NULL);
-
- gtk_signal_connect (GTK_OBJECT (scale_data), "value_changed",
- GTK_SIGNAL_FUNC (gimp_double_adjustment_update),
- &evals.amount);
-
- /* Radio buttons WRAP, SMEAR, BLACK */
-
- hbox = gtk_hbox_new (FALSE, 4);
- gtk_table_attach (GTK_TABLE (table), hbox, 0, 3, 1, 2,
- GTK_FILL, GTK_FILL, 0, 0);
-
- toggle = gtk_radio_button_new_with_label (group, _("Wrap"));
- group = gtk_radio_button_group (GTK_RADIO_BUTTON (toggle));
- gtk_box_pack_start (GTK_BOX (hbox), toggle, TRUE, TRUE, 0);
- gtk_signal_connect (GTK_OBJECT (toggle), "toggled",
- GTK_SIGNAL_FUNC (gimp_toggle_button_update),
- &use_wrap);
- gtk_toggle_button_set_active (GTK_TOGGLE_BUTTON (toggle), use_wrap);
- gtk_widget_show (toggle);
-
- toggle = gtk_radio_button_new_with_label (group, _("Smear"));
- group = gtk_radio_button_group (GTK_RADIO_BUTTON (toggle));
- gtk_box_pack_start (GTK_BOX (hbox), toggle, TRUE, TRUE, 0);
- gtk_signal_connect (GTK_OBJECT (toggle), "toggled",
- GTK_SIGNAL_FUNC (gimp_toggle_button_update),
- &use_smear);
- gtk_toggle_button_set_active (GTK_TOGGLE_BUTTON (toggle), use_smear);
- gtk_widget_show (toggle);
-
- toggle = gtk_radio_button_new_with_label (group, _("Black"));
- group = gtk_radio_button_group (GTK_RADIO_BUTTON (toggle));
- gtk_box_pack_start (GTK_BOX (hbox), toggle, TRUE, TRUE, 0);
- gtk_signal_connect (GTK_OBJECT (toggle), "toggled",
- GTK_SIGNAL_FUNC (gimp_toggle_button_update),
- &use_black);
- gtk_toggle_button_set_active (GTK_TOGGLE_BUTTON (toggle), use_black);
- gtk_widget_show (toggle);
- gtk_widget_show (hbox);
-
- gtk_widget_show (table);
- gtk_widget_show (frame);
- gtk_widget_show (dlg);
-
- gtk_main ();
- gdk_flush ();
-
- if (use_wrap)
- evals.wrapmode = WRAP;
- else if (use_smear)
- evals.wrapmode = SMEAR;
- else if (use_black)
- evals.wrapmode = BLACK;
-
- return eint.run;
- }
-