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-rw-r--r--plug-ins/common/photocopy.c935
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diff --git a/plug-ins/common/photocopy.c b/plug-ins/common/photocopy.c
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+++ b/plug-ins/common/photocopy.c
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+/* GIMP - The GNU 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 3 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, see <https://www.gnu.org/licenses/>.
+ */
+
+/* Photocopy filter for GIMP for BIPS
+ * -Spencer Kimball
+ *
+ * This filter propagates dark values in an image based on
+ * each pixel's relative darkness to a neighboring average
+ * and sets the remaining pixels to white.
+ */
+
+#include "config.h"
+
+#include <string.h>
+
+#include <libgimp/gimp.h>
+#include <libgimp/gimpui.h>
+
+#include "libgimp/stdplugins-intl.h"
+
+
+/* Some useful macros */
+
+#define PLUG_IN_PROC "plug-in-photocopy"
+#define PLUG_IN_BINARY "photocopy"
+#define PLUG_IN_ROLE "gimp-photocopy"
+#define TILE_CACHE_SIZE 48
+#define GAMMA 1.0
+#define EPSILON 2
+
+
+typedef struct
+{
+ gdouble mask_radius;
+ gdouble sharpness;
+ gdouble threshold;
+ gdouble pct_black;
+ gdouble pct_white;
+} PhotocopyVals;
+
+
+/*
+ * Function prototypes.
+ */
+
+static void query (void);
+static void run (const gchar *name,
+ gint nparams,
+ const GimpParam *param,
+ gint *nreturn_vals,
+ GimpParam **return_vals);
+
+static void photocopy (GimpDrawable *drawable,
+ GimpPreview *preview);
+static gboolean photocopy_dialog (GimpDrawable *drawable);
+
+static gdouble compute_ramp (guchar *dest1,
+ guchar *dest2,
+ gint length,
+ gdouble pct_black,
+ gint under_threshold);
+
+/*
+ * Gaussian blur helper functions
+ */
+static void find_constants (gdouble n_p[],
+ gdouble n_m[],
+ gdouble d_p[],
+ gdouble d_m[],
+ gdouble bd_p[],
+ gdouble bd_m[],
+ gdouble std_dev);
+static void transfer_pixels (gdouble *src1,
+ gdouble *src2,
+ guchar *dest,
+ gint jump,
+ gint width);
+
+/***** Local vars *****/
+
+const GimpPlugInInfo PLUG_IN_INFO =
+{
+ NULL, /* init */
+ NULL, /* quit */
+ query, /* query */
+ run, /* run */
+};
+
+static PhotocopyVals pvals =
+{
+ 8.0, /* mask_radius */
+ 0.8, /* sharpness */
+ 0.75, /* threshold */
+ 0.2, /* pct_black */
+ 0.2 /* pct_white */
+};
+
+
+/***** Functions *****/
+
+MAIN ()
+
+static void
+query (void)
+{
+ static const GimpParamDef args[] =
+ {
+ { GIMP_PDB_INT32, "run-mode", "The run mode { RUN-INTERACTIVE (0), RUN-NONINTERACTIVE (1) }" },
+ { GIMP_PDB_IMAGE, "image", "Input image (unused)" },
+ { GIMP_PDB_DRAWABLE, "drawable", "Input drawable" },
+ { GIMP_PDB_FLOAT, "mask-radius", "Photocopy mask radius (radius of pixel neighborhood)" },
+ { GIMP_PDB_FLOAT, "sharpness", "Sharpness (detail level) (0.0 - 1.0)" },
+ { GIMP_PDB_FLOAT, "pct-black", "Percentage of darkened pixels to set to black (0.0 - 1.0)" },
+ { GIMP_PDB_FLOAT, "pct-white", "Percentage of non-darkened pixels left white (0.0 - 1.0)" }
+ };
+
+ gchar *help_string =
+ "Propagates dark values in an image based on "
+ "each pixel's relative darkness to a neighboring average. The idea behind "
+ "this filter is to give the look of a photocopied version of the image, "
+ "with toner transferred based on the relative darkness of a particular "
+ "region. This is achieved by darkening areas of the image which are "
+ "measured to be darker than a neighborhood average and setting other "
+ "pixels to white. In this way, sufficiently large shifts in intensity "
+ "are darkened to black. The rate at which they are darkened to black is "
+ "determined by the second pct_black parameter. The mask_radius parameter "
+ "controls the size of the pixel neighborhood over which the average "
+ "intensity is computed and then compared to each pixel in the neighborhood "
+ "to decide whether or not to darken it to black. Large values for "
+ "mask_radius result in very thick black areas bordering the regions "
+ "of white and much less detail for black areas everywhere including "
+ "inside regions of color. Small values result in less toner overall "
+ "and more detail everywhere. Small values for the pct_black make the "
+ "blend from the white regions to the black border lines smoother and "
+ "the toner regions themselves thinner and less noticeable; larger values "
+ "achieve the opposite effect.";
+
+ gimp_install_procedure (PLUG_IN_PROC,
+ N_("Simulate color distortion produced by a copy machine"),
+ help_string,
+ "Spencer Kimball",
+ "Bit Specialists, Inc.",
+ "2001",
+ N_("_Photocopy (legacy)..."),
+ "RGB*, GRAY*",
+ GIMP_PLUGIN,
+ G_N_ELEMENTS (args), 0,
+ args, NULL);
+
+ gimp_plugin_menu_register (PLUG_IN_PROC, "<Image>/Filters/Artistic");
+}
+
+static void
+run (const gchar *name,
+ gint nparams,
+ const GimpParam *param,
+ gint *nreturn_vals,
+ GimpParam **return_vals)
+{
+ static GimpParam values[2];
+ GimpRunMode run_mode;
+ GimpDrawable *drawable;
+ 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);
+
+ /* set the tile cache size */
+ gimp_tile_cache_ntiles (TILE_CACHE_SIZE);
+
+ *nreturn_vals = 1;
+ *return_vals = values;
+
+ values[0].type = GIMP_PDB_STATUS;
+ values[0].data.d_status = status;
+
+ INIT_I18N();
+
+ switch (run_mode)
+ {
+ case GIMP_RUN_INTERACTIVE:
+ /* Possibly retrieve data */
+ gimp_get_data (PLUG_IN_PROC, &pvals);
+
+ /* First acquire information with a dialog */
+ if (! photocopy_dialog (drawable))
+ return;
+ break;
+
+ case GIMP_RUN_NONINTERACTIVE:
+ pvals.mask_radius = param[3].data.d_float;
+ pvals.sharpness = param[4].data.d_float;
+ pvals.pct_black = param[5].data.d_float;
+ pvals.pct_white = param[6].data.d_float;
+ break;
+
+ case GIMP_RUN_WITH_LAST_VALS:
+ /* Possibly retrieve data */
+ gimp_get_data (PLUG_IN_PROC, &pvals);
+ break;
+
+ default:
+ break;
+ }
+
+ if (status == GIMP_PDB_SUCCESS)
+ {
+ /* Make sure that the drawable is RGB or GRAY color */
+ if (gimp_drawable_is_rgb (drawable->drawable_id) ||
+ gimp_drawable_is_gray (drawable->drawable_id))
+ {
+ gimp_progress_init ("Photocopy");
+
+ photocopy (drawable, NULL);
+
+ if (run_mode != GIMP_RUN_NONINTERACTIVE)
+ gimp_displays_flush ();
+
+ /* Store data */
+ if (run_mode == GIMP_RUN_INTERACTIVE)
+ gimp_set_data (PLUG_IN_PROC, &pvals, sizeof (PhotocopyVals));
+ }
+ else
+ {
+ status = GIMP_PDB_EXECUTION_ERROR;
+ *nreturn_vals = 2;
+ values[1].type = GIMP_PDB_STRING;
+ values[1].data.d_string = _("Cannot operate on indexed color images.");
+ }
+ }
+
+ values[0].data.d_status = status;
+
+ gimp_drawable_detach (drawable);
+}
+
+/*
+ * Photocopy algorithm
+ * -----------------
+ * Mask radius = radius of pixel neighborhood for intensity comparison
+ * Threshold = relative intensity difference which will result in darkening
+ * Ramp = amount of relative intensity difference before total black
+ * Blur radius = mask radius / 3.0
+ *
+ * Algorithm:
+ * For each pixel, calculate pixel intensity value to be: avg (blur radius)
+ * relative diff = pixel intensity / avg (mask radius)
+ * If relative diff < Threshold
+ * intensity mult = (Ramp - MIN (Ramp, (Threshold - relative diff))) / Ramp
+ * pixel intensity *= intensity mult
+ * Else
+ * pixel intensity = white
+ */
+static void
+photocopy (GimpDrawable *drawable,
+ GimpPreview *preview)
+{
+ GimpPixelRgn src_rgn, dest_rgn;
+ GimpPixelRgn *pr;
+ gint x, y, width, height;
+ gint bytes;
+ gboolean has_alpha;
+ guchar *dest1;
+ guchar *dest2;
+ guchar *src1, *sp_p1, *sp_m1;
+ guchar *src2, *sp_p2, *sp_m2;
+ gdouble n_p1[5], n_m1[5];
+ gdouble n_p2[5], n_m2[5];
+ gdouble d_p1[5], d_m1[5];
+ gdouble d_p2[5], d_m2[5];
+ gdouble bd_p1[5], bd_m1[5];
+ gdouble bd_p2[5], bd_m2[5];
+ gdouble *val_p1, *val_m1, *vp1, *vm1;
+ gdouble *val_p2, *val_m2, *vp2, *vm2;
+ gint i, j;
+ gint row, col;
+ gint terms;
+ gint progress, max_progress;
+ gint initial_p1[4];
+ gint initial_p2[4];
+ gint initial_m1[4];
+ gint initial_m2[4];
+ gdouble radius;
+ gdouble val;
+ gdouble std_dev1;
+ gdouble std_dev2;
+ gdouble ramp_down;
+ gdouble ramp_up;
+
+ if (preview)
+ {
+ gimp_preview_get_position (preview, &x, &y);
+ gimp_preview_get_size (preview, &width, &height);
+ }
+ else
+ {
+ if (! gimp_drawable_mask_intersect (drawable->drawable_id,
+ &x, &y, &width, &height))
+ return;
+ }
+
+ bytes = drawable->bpp;
+ has_alpha = gimp_drawable_has_alpha (drawable->drawable_id);
+
+ val_p1 = g_new (gdouble, MAX (width, height));
+ val_p2 = g_new (gdouble, MAX (width, height));
+ val_m1 = g_new (gdouble, MAX (width, height));
+ val_m2 = g_new (gdouble, MAX (width, height));
+
+ dest1 = g_new0 (guchar, width * height);
+ dest2 = g_new0 (guchar, width * height);
+
+ progress = 0;
+ max_progress = width * height * 3;
+
+ gimp_pixel_rgn_init (&src_rgn, drawable,
+ x, y, width, height, FALSE, FALSE);
+
+ for (pr = gimp_pixel_rgns_register (1, &src_rgn);
+ pr != NULL;
+ pr = gimp_pixel_rgns_process (pr))
+ {
+ guchar *src_ptr = src_rgn.data;
+ guchar *dest_ptr = dest1 + (src_rgn.y - y) * width + (src_rgn.x - x);
+
+ for (row = 0; row < src_rgn.h; row++)
+ {
+ for (col = 0; col < src_rgn.w; col++)
+ {
+ /* desaturate */
+ if (bytes > 2)
+ dest_ptr[col] = (guchar) gimp_rgb_to_l_int (src_ptr[col * bytes + 0],
+ src_ptr[col * bytes + 1],
+ src_ptr[col * bytes + 2]);
+ else
+ dest_ptr[col] = (guchar) src_ptr[col * bytes];
+
+ /* compute transfer */
+ val = pow (dest_ptr[col], (1.0 / GAMMA));
+ dest_ptr[col] = (guchar) CLAMP (val, 0, 255);
+ }
+
+ src_ptr += src_rgn.rowstride;
+ dest_ptr += width;
+ }
+
+ if (!preview)
+ {
+ progress += src_rgn.w * src_rgn.h;
+ gimp_progress_update ((gdouble) progress / (gdouble) max_progress);
+ }
+ }
+
+ /* Calculate the standard deviations */
+ radius = MAX (1.0, 10 * (1.0 - pvals.sharpness));
+ radius = fabs (radius) + 1.0;
+ std_dev1 = sqrt (-(radius * radius) / (2 * log (1.0 / 255.0)));
+
+ radius = fabs (pvals.mask_radius) + 1.0;
+ std_dev2 = sqrt (-(radius * radius) / (2 * log (1.0 / 255.0)));
+
+ /* derive the constants for calculating the gaussian from the std dev */
+ find_constants (n_p1, n_m1, d_p1, d_m1, bd_p1, bd_m1, std_dev1);
+ find_constants (n_p2, n_m2, d_p2, d_m2, bd_p2, bd_m2, std_dev2);
+
+ /* First the vertical pass */
+ for (col = 0; col < width; col++)
+ {
+ memset (val_p1, 0, height * sizeof (gdouble));
+ memset (val_p2, 0, height * sizeof (gdouble));
+ memset (val_m1, 0, height * sizeof (gdouble));
+ memset (val_m2, 0, height * sizeof (gdouble));
+
+ src1 = dest1 + col;
+ sp_p1 = src1;
+ sp_m1 = src1 + (height - 1) * width;
+ vp1 = val_p1;
+ vp2 = val_p2;
+ vm1 = val_m1 + (height - 1);
+ vm2 = val_m2 + (height - 1);
+
+ /* Set up the first vals */
+ initial_p1[0] = sp_p1[0];
+ initial_m1[0] = sp_m1[0];
+
+ for (row = 0; row < height; row++)
+ {
+ gdouble *vpptr1, *vmptr1;
+ gdouble *vpptr2, *vmptr2;
+
+ terms = (row < 4) ? row : 4;
+
+ vpptr1 = vp1; vmptr1 = vm1;
+ vpptr2 = vp2; vmptr2 = vm2;
+
+ for (i = 0; i <= terms; i++)
+ {
+ *vpptr1 += n_p1[i] * sp_p1[-i * width] - d_p1[i] * vp1[-i];
+ *vmptr1 += n_m1[i] * sp_m1[i * width] - d_m1[i] * vm1[i];
+
+ *vpptr2 += n_p2[i] * sp_p1[-i * width] - d_p2[i] * vp2[-i];
+ *vmptr2 += n_m2[i] * sp_m1[i * width] - d_m2[i] * vm2[i];
+ }
+
+ for (j = i; j <= 4; j++)
+ {
+ *vpptr1 += (n_p1[j] - bd_p1[j]) * initial_p1[0];
+ *vmptr1 += (n_m1[j] - bd_m1[j]) * initial_m1[0];
+
+ *vpptr2 += (n_p2[j] - bd_p2[j]) * initial_p1[0];
+ *vmptr2 += (n_m2[j] - bd_m2[j]) * initial_m1[0];
+ }
+
+ sp_p1 += width;
+ sp_m1 -= width;
+ vp1 += 1;
+ vp2 += 1;
+ vm1 -= 1;
+ vm2 -= 1;
+ }
+
+ transfer_pixels (val_p1, val_m1, dest1 + col, width, height);
+ transfer_pixels (val_p2, val_m2, dest2 + col, width, height);
+
+ if (!preview)
+ {
+ progress += height;
+ if ((col % 5) == 0)
+ gimp_progress_update ((gdouble) progress / (gdouble) max_progress);
+ }
+ }
+
+ for (row = 0; row < height; row++)
+ {
+ memset (val_p1, 0, width * sizeof (gdouble));
+ memset (val_p2, 0, width * sizeof (gdouble));
+ memset (val_m1, 0, width * sizeof (gdouble));
+ memset (val_m2, 0, width * sizeof (gdouble));
+
+ src1 = dest1 + row * width;
+ src2 = dest2 + row * width;
+
+ sp_p1 = src1;
+ sp_p2 = src2;
+ sp_m1 = src1 + width - 1;
+ sp_m2 = src2 + width - 1;
+ vp1 = val_p1;
+ vp2 = val_p2;
+ vm1 = val_m1 + width - 1;
+ vm2 = val_m2 + width - 1;
+
+ /* Set up the first vals */
+ initial_p1[0] = sp_p1[0];
+ initial_p2[0] = sp_p2[0];
+ initial_m1[0] = sp_m1[0];
+ initial_m2[0] = sp_m2[0];
+
+ for (col = 0; col < width; col++)
+ {
+ gdouble *vpptr1, *vmptr1;
+ gdouble *vpptr2, *vmptr2;
+
+ terms = (col < 4) ? col : 4;
+
+ vpptr1 = vp1; vmptr1 = vm1;
+ vpptr2 = vp2; vmptr2 = vm2;
+
+ for (i = 0; i <= terms; i++)
+ {
+ *vpptr1 += n_p1[i] * sp_p1[-i] - d_p1[i] * vp1[-i];
+ *vmptr1 += n_m1[i] * sp_m1[i] - d_m1[i] * vm1[i];
+
+ *vpptr2 += n_p2[i] * sp_p2[-i] - d_p2[i] * vp2[-i];
+ *vmptr2 += n_m2[i] * sp_m2[i] - d_m2[i] * vm2[i];
+ }
+
+ for (j = i; j <= 4; j++)
+ {
+ *vpptr1 += (n_p1[j] - bd_p1[j]) * initial_p1[0];
+ *vmptr1 += (n_m1[j] - bd_m1[j]) * initial_m1[0];
+
+ *vpptr2 += (n_p2[j] - bd_p2[j]) * initial_p2[0];
+ *vmptr2 += (n_m2[j] - bd_m2[j]) * initial_m2[0];
+ }
+
+ sp_p1 ++;
+ sp_p2 ++;
+ sp_m1 --;
+ sp_m2 --;
+ vp1 ++;
+ vp2 ++;
+ vm1 --;
+ vm2 --;
+ }
+
+ transfer_pixels (val_p1, val_m1, dest1 + row * width, 1, width);
+ transfer_pixels (val_p2, val_m2, dest2 + row * width, 1, width);
+
+ if (!preview)
+ {
+ progress += width;
+ if ((row % 5) == 0)
+ gimp_progress_update ((gdouble) progress / (gdouble) max_progress);
+ }
+ }
+
+ /* Compute the ramp value which sets 'pct_black' % of the darkened pixels black */
+ ramp_down = compute_ramp (dest1, dest2, width * height, pvals.pct_black, 1);
+ ramp_up = compute_ramp (dest1, dest2, width * height, 1.0 - pvals.pct_white, 0);
+
+ /* Initialize the pixel regions. */
+ gimp_pixel_rgn_init (&src_rgn, drawable, x, y, width, height, FALSE, FALSE);
+ gimp_pixel_rgn_init (&dest_rgn, drawable, x, y, width, height,
+ (preview == NULL), TRUE);
+
+ pr = gimp_pixel_rgns_register (2, &src_rgn, &dest_rgn);
+
+ while (pr)
+ {
+ guchar *src_ptr = src_rgn.data;
+ guchar *dest_ptr = dest_rgn.data;
+ guchar *blur_ptr = dest1 + (src_rgn.y - y) * width + (src_rgn.x - x);
+ guchar *avg_ptr = dest2 + (src_rgn.y - y) * width + (src_rgn.x - x);
+ gdouble diff, mult;
+ gdouble lightness = 0.0;
+
+ for (row = 0; row < src_rgn.h; row++)
+ {
+ for (col = 0; col < src_rgn.w; col++)
+ {
+ if (avg_ptr[col] > EPSILON)
+ {
+ diff = (gdouble) blur_ptr[col] / (gdouble) avg_ptr[col];
+
+ if (diff < pvals.threshold)
+ {
+ if (ramp_down == 0.0)
+ mult = 0.0;
+ else
+ mult = (ramp_down - MIN (ramp_down,
+ (pvals.threshold - diff))) / ramp_down;
+ lightness = CLAMP (blur_ptr[col] * mult, 0, 255);
+ }
+ else
+ {
+ if (ramp_up == 0.0)
+ mult = 1.0;
+ else
+ mult = MIN (ramp_up,
+ (diff - pvals.threshold)) / ramp_up;
+
+ lightness = 255 - (1.0 - mult) * (255 - blur_ptr[col]);
+ lightness = CLAMP (lightness, 0, 255);
+ }
+ }
+ else
+ {
+ lightness = 0;
+ }
+
+ if (bytes < 3)
+ {
+ dest_ptr[col * bytes] = (guchar) lightness;
+ if (has_alpha)
+ dest_ptr[col * bytes + 1] = src_ptr[col * src_rgn.bpp + 1];
+ }
+ else
+ {
+ dest_ptr[col * bytes + 0] = lightness;
+ dest_ptr[col * bytes + 1] = lightness;
+ dest_ptr[col * bytes + 2] = lightness;
+
+ if (has_alpha)
+ dest_ptr[col * bytes + 3] = src_ptr[col * src_rgn.bpp + 3];
+ }
+ }
+
+ src_ptr += src_rgn.rowstride;
+ dest_ptr += dest_rgn.rowstride;
+ blur_ptr += width;
+ avg_ptr += width;
+ }
+
+ if (preview)
+ {
+ gimp_drawable_preview_draw_region (GIMP_DRAWABLE_PREVIEW (preview),
+ &dest_rgn);
+ }
+ else
+ {
+ progress += src_rgn.w * src_rgn.h;
+ gimp_progress_update ((gdouble) progress / (gdouble) max_progress);
+ }
+
+ pr = gimp_pixel_rgns_process (pr);
+ }
+
+ if (! preview)
+ {
+ gimp_progress_update (1.0);
+ /* merge the shadow, update the drawable */
+ gimp_drawable_flush (drawable);
+ gimp_drawable_merge_shadow (drawable->drawable_id, TRUE);
+ gimp_drawable_update (drawable->drawable_id, x, y, width, height);
+ }
+
+ /* free up buffers */
+ g_free (val_p1);
+ g_free (val_p2);
+ g_free (val_m1);
+ g_free (val_m2);
+ g_free (dest1);
+ g_free (dest2);
+}
+
+static gdouble
+compute_ramp (guchar *dest1,
+ guchar *dest2,
+ gint length,
+ gdouble pct,
+ gint under_threshold)
+{
+ gint hist[2000];
+ gdouble diff;
+ gint count;
+ gint i;
+ gint sum;
+
+ memset (hist, 0, sizeof (int) * 2000);
+ count = 0;
+
+ for (i = 0; i < length; i++)
+ {
+ if (*dest2 != 0)
+ {
+ diff = (gdouble) *dest1 / (gdouble) *dest2;
+
+ if (under_threshold)
+ {
+ if (diff < pvals.threshold)
+ {
+ hist[(int) (diff * 1000)] += 1;
+ count += 1;
+ }
+ }
+ else
+ {
+ if (diff >= pvals.threshold && diff < 2.0)
+ {
+ hist[(int) (diff * 1000)] += 1;
+ count += 1;
+ }
+ }
+ }
+
+ dest1++;
+ dest2++;
+ }
+
+ if (pct == 0.0 || count == 0)
+ return (under_threshold ? 1.0 : 0.0);
+
+ sum = 0;
+ for (i = 0; i < 2000; i++)
+ {
+ sum += hist[i];
+ if (((gdouble) sum / (gdouble) count) > pct)
+ {
+ if (under_threshold)
+ return (pvals.threshold - (gdouble) i / 1000.0);
+ else
+ return ((gdouble) i / 1000.0 - pvals.threshold);
+ }
+ }
+
+ return (under_threshold ? 0.0 : 1.0);
+}
+
+
+/*
+ * Gaussian blur helper functions
+ */
+
+static void
+transfer_pixels (gdouble *src1,
+ gdouble *src2,
+ guchar *dest,
+ gint jump,
+ gint width)
+{
+ gint i;
+ gdouble sum;
+
+ for(i = 0; i < width; i++)
+ {
+ sum = src1[i] + src2[i];
+ if (sum > 255) sum = 255;
+ else if(sum < 0) sum = 0;
+
+ *dest = (guchar) sum;
+
+ dest += jump;
+ }
+}
+
+static void
+find_constants (gdouble n_p[],
+ gdouble n_m[],
+ gdouble d_p[],
+ gdouble d_m[],
+ gdouble bd_p[],
+ gdouble bd_m[],
+ gdouble std_dev)
+{
+ gint i;
+ gdouble constants [8];
+ gdouble div;
+
+ /* The constants used in the implementation of a casual sequence
+ * using a 4th order approximation of the gaussian operator
+ */
+
+ div = sqrt (2 * G_PI) * std_dev;
+ constants [0] = -1.783 / std_dev;
+ constants [1] = -1.723 / std_dev;
+ constants [2] = 0.6318 / std_dev;
+ constants [3] = 1.997 / std_dev;
+ constants [4] = 1.6803 / div;
+ constants [5] = 3.735 / div;
+ constants [6] = -0.6803 / div;
+ constants [7] = -0.2598 / div;
+
+ n_p [0] = constants[4] + constants[6];
+ n_p [1] = exp (constants[1]) *
+ (constants[7] * sin (constants[3]) -
+ (constants[6] + 2 * constants[4]) * cos (constants[3])) +
+ exp (constants[0]) *
+ (constants[5] * sin (constants[2]) -
+ (2 * constants[6] + constants[4]) * cos (constants[2]));
+ n_p [2] = 2 * exp (constants[0] + constants[1]) *
+ ((constants[4] + constants[6]) * cos (constants[3]) * cos (constants[2]) -
+ constants[5] * cos (constants[3]) * sin (constants[2]) -
+ constants[7] * cos (constants[2]) * sin (constants[3])) +
+ constants[6] * exp (2 * constants[0]) +
+ constants[4] * exp (2 * constants[1]);
+ n_p [3] = exp (constants[1] + 2 * constants[0]) *
+ (constants[7] * sin (constants[3]) - constants[6] * cos (constants[3])) +
+ exp (constants[0] + 2 * constants[1]) *
+ (constants[5] * sin (constants[2]) - constants[4] * cos (constants[2]));
+ n_p [4] = 0.0;
+
+ d_p [0] = 0.0;
+ d_p [1] = -2 * exp (constants[1]) * cos (constants[3]) -
+ 2 * exp (constants[0]) * cos (constants[2]);
+ d_p [2] = 4 * cos (constants[3]) * cos (constants[2]) * exp (constants[0] + constants[1]) +
+ exp (2 * constants[1]) + exp (2 * constants[0]);
+ d_p [3] = -2 * cos (constants[2]) * exp (constants[0] + 2 * constants[1]) -
+ 2 * cos (constants[3]) * exp (constants[1] + 2 * constants[0]);
+ d_p [4] = exp (2 * constants[0] + 2 * constants[1]);
+
+#ifndef ORIGINAL_READABLE_CODE
+ memcpy(d_m, d_p, 5 * sizeof(gdouble));
+#else
+ for (i = 0; i <= 4; i++)
+ d_m [i] = d_p [i];
+#endif
+
+ n_m[0] = 0.0;
+ for (i = 1; i <= 4; i++)
+ n_m [i] = n_p[i] - d_p[i] * n_p[0];
+
+ {
+ gdouble sum_n_p, sum_n_m, sum_d;
+ gdouble a, b;
+
+ sum_n_p = 0.0;
+ sum_n_m = 0.0;
+ sum_d = 0.0;
+
+ for (i = 0; i <= 4; i++)
+ {
+ sum_n_p += n_p[i];
+ sum_n_m += n_m[i];
+ sum_d += d_p[i];
+ }
+
+#ifndef ORIGINAL_READABLE_CODE
+ sum_d++;
+ a = sum_n_p / sum_d;
+ b = sum_n_m / sum_d;
+#else
+ a = sum_n_p / (1 + sum_d);
+ b = sum_n_m / (1 + sum_d);
+#endif
+
+ for (i = 0; i <= 4; i++)
+ {
+ bd_p[i] = d_p[i] * a;
+ bd_m[i] = d_m[i] * b;
+ }
+ }
+}
+
+/*******************************************************/
+/* Dialog */
+/*******************************************************/
+
+static gboolean
+photocopy_dialog (GimpDrawable *drawable)
+{
+ GtkWidget *dialog;
+ GtkWidget *main_vbox;
+ GtkWidget *preview;
+ GtkWidget *table;
+ GtkObject *scale_data;
+ gboolean run;
+
+ gimp_ui_init (PLUG_IN_BINARY, FALSE);
+
+ dialog = gimp_dialog_new (_("Photocopy"), PLUG_IN_ROLE,
+ NULL, 0,
+ gimp_standard_help_func, PLUG_IN_PROC,
+
+ _("_Cancel"), GTK_RESPONSE_CANCEL,
+ _("_OK"), GTK_RESPONSE_OK,
+
+ NULL);
+
+ gtk_dialog_set_alternative_button_order (GTK_DIALOG (dialog),
+ GTK_RESPONSE_OK,
+ GTK_RESPONSE_CANCEL,
+ -1);
+
+ gimp_window_set_transient (GTK_WINDOW (dialog));
+
+ main_vbox = gtk_box_new (GTK_ORIENTATION_VERTICAL, 12);
+ gtk_container_set_border_width (GTK_CONTAINER (main_vbox), 12);
+ gtk_box_pack_start (GTK_BOX (gtk_dialog_get_content_area (GTK_DIALOG (dialog))),
+ main_vbox, TRUE, TRUE, 0);
+ gtk_widget_show (main_vbox);
+
+ preview = gimp_drawable_preview_new_from_drawable_id (drawable->drawable_id);
+ gtk_box_pack_start (GTK_BOX (main_vbox), preview, TRUE, TRUE, 0);
+ gtk_widget_show (preview);
+
+ g_signal_connect_swapped (preview, "invalidated",
+ G_CALLBACK (photocopy),
+ drawable);
+
+ table = gtk_table_new (4, 3, FALSE);
+ gtk_table_set_col_spacings (GTK_TABLE (table), 6);
+ gtk_table_set_row_spacings (GTK_TABLE (table), 6);
+ gtk_box_pack_start (GTK_BOX (main_vbox), table, FALSE, FALSE, 0);
+ gtk_widget_show (table);
+
+ /* Label, scale, entry for pvals.amount */
+ scale_data = gimp_scale_entry_new (GTK_TABLE (table), 0, 0,
+ _("_Mask radius:"), 100, 5,
+ pvals.mask_radius, 3.0, 50.0, 1, 5.0, 2,
+ TRUE, 0, 0,
+ NULL, NULL);
+
+ g_signal_connect (scale_data, "value-changed",
+ G_CALLBACK (gimp_double_adjustment_update),
+ &pvals.mask_radius);
+ g_signal_connect_swapped (scale_data, "value-changed",
+ G_CALLBACK (gimp_preview_invalidate),
+ preview);
+
+ /* Label, scale, entry for pvals.amount */
+ scale_data = gimp_scale_entry_new (GTK_TABLE (table), 0, 1,
+ _("_Sharpness:"), 50, 5,
+ pvals.sharpness, 0.0, 1.0, 0.01, 0.1, 3,
+ TRUE, 0, 0,
+ NULL, NULL);
+
+ g_signal_connect (scale_data, "value-changed",
+ G_CALLBACK (gimp_double_adjustment_update),
+ &pvals.sharpness);
+ g_signal_connect_swapped (scale_data, "value-changed",
+ G_CALLBACK (gimp_preview_invalidate),
+ preview);
+
+ /* Label, scale, entry for pvals.amount */
+ scale_data = gimp_scale_entry_new (GTK_TABLE (table), 0, 2,
+ _("Percent _black:"), 50, 5,
+ pvals.pct_black, 0.0, 1.0, 0.01, 0.1, 3,
+ TRUE, 0, 0,
+ NULL, NULL);
+
+ g_signal_connect (scale_data, "value-changed",
+ G_CALLBACK (gimp_double_adjustment_update),
+ &pvals.pct_black);
+ g_signal_connect_swapped (scale_data, "value-changed",
+ G_CALLBACK (gimp_preview_invalidate),
+ preview);
+
+ /* Label, scale, entry for pvals.amount */
+ scale_data = gimp_scale_entry_new (GTK_TABLE (table), 0, 3,
+ _("Percent _white:"), 50, 5,
+ pvals.pct_white, 0.0, 1.0, 0.01, 0.1, 3,
+ TRUE, 0, 0,
+ NULL, NULL);
+
+ g_signal_connect (scale_data, "value-changed",
+ G_CALLBACK (gimp_double_adjustment_update),
+ &pvals.pct_white);
+ g_signal_connect_swapped (scale_data, "value-changed",
+ G_CALLBACK (gimp_preview_invalidate),
+ preview);
+
+ gtk_widget_show (dialog);
+
+ run = (gimp_dialog_run (GIMP_DIALOG (dialog)) == GTK_RESPONSE_OK);
+
+ gtk_widget_destroy (dialog);
+
+ return run;
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-14 10:19:37 +0000