/* This file is an image processing operation for GEGL
*
* GEGL is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 3 of the License, or (at your option) any later version.
*
* GEGL 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with GEGL; if not, see <http://www.gnu.org/licenses/>.
*
* Copyright 2006 Øyvind Kolås <pippin@gimp.org>
*/
#include "config.h"
#include <glib/gi18n-lib.h>
#ifdef GEGL_CHANT_PROPERTIES
gegl_chant_double (radius, _("Radius"), 0.0, 200.0, 4.0,
_("Radius of square pixel region (width and height will be radius*2+1)"))
#else
#define GEGL_CHANT_TYPE_AREA_FILTER
#define GEGL_CHANT_C_FILE "box-min.c"
#include "gegl-chant.h"
#include <stdio.h>
#include <math.h>
static inline gfloat
get_min_component (gfloat *buf,
gint buf_width,
gint buf_height,
gint x0,
gint y0,
gint width,
gint height,
gint component)
{
gint x, y;
gfloat min=1000000000.0;
gint count=0;
gint offset = (y0 * buf_width + x0) * 4 + component;
for (y=y0; y<y0+height; y++)
{
for (x=x0; x<x0+width; x++)
{
if (x>=0 && x<buf_width &&
y>=0 && y<buf_height)
{
if (buf [offset] < min)
min = buf[offset];
count++;
}
offset+=4;
}
offset+= (buf_width * 4) - 4 * width;
}
return min;
}
static void
hor_min (GeglBuffer *src,
const GeglRectangle *src_rect,
GeglBuffer *dst,
const GeglRectangle *dst_rect,
gint radius)
{
gint u,v;
gint offset;
gfloat *src_buf;
gfloat *dst_buf;
src_buf = g_new0 (gfloat, src_rect->width * src_rect->height * 4);
dst_buf = g_new0 (gfloat, dst_rect->width * dst_rect->height * 4);
gegl_buffer_get (src, src_rect, 1.0, babl_format ("RGBA float"), src_buf,
GEGL_AUTO_ROWSTRIDE, GEGL_ABYSS_NONE);
offset = 0;
for (v=0; v<dst_rect->height; v++)
for (u=0; u<dst_rect->width; u++)
{
gint i;
for (i=0; i<4; i++)
dst_buf [offset++] = get_min_component (src_buf,
src_rect->width,
src_rect->height,
u + radius - radius,
v + radius,
1 + radius*2,
1,
i);
}
gegl_buffer_set (dst, dst_rect, 0, babl_format ("RGBA float"), dst_buf,
GEGL_AUTO_ROWSTRIDE);
g_free (src_buf);
g_free (dst_buf);
}
static void
ver_min (GeglBuffer *src,
const GeglRectangle *src_rect,
GeglBuffer *dst,
const GeglRectangle *dst_rect,
gint radius)
{
gint u,v;
gint offset;
gfloat *src_buf;
gfloat *dst_buf;
src_buf = g_new0 (gfloat, src_rect->width * src_rect->height * 4);
dst_buf = g_new0 (gfloat, dst_rect->width * src_rect->height * 4);
gegl_buffer_get (src, src_rect, 1.0, babl_format ("RGBA float"), src_buf,
GEGL_AUTO_ROWSTRIDE, GEGL_ABYSS_NONE);
offset=0;
for (v=0; v<dst_rect->height; v++)
for (u=0; u<dst_rect->width; u++)
{
gint c;
for (c=0; c<4; c++)
dst_buf [offset++] =
get_min_component (src_buf,
src_rect->width,
src_rect->height,
u,
v - radius,
1,
1 + radius * 2,
c);
}
gegl_buffer_set (dst, dst_rect, 0, babl_format ("RGBA float"), dst_buf,
GEGL_AUTO_ROWSTRIDE);
g_free (src_buf);
g_free (dst_buf);
}
static void prepare (GeglOperation *operation)
{
GeglOperationAreaFilter *area = GEGL_OPERATION_AREA_FILTER (operation);
area->left =
area->right =
area->top =
area->bottom = GEGL_CHANT_PROPERTIES (operation)->radius;
gegl_operation_set_format (operation, "output", babl_format ("RGBA float"));
}
static gboolean
process (GeglOperation *operation,
GeglBuffer *input,
GeglBuffer *output,
const GeglRectangle *result,
gint level)
{
GeglChantO *o = GEGL_CHANT_PROPERTIES (operation);
GeglRectangle input_rect = gegl_operation_get_required_for_output (operation, "input", result);
hor_min ( input, &input_rect, output, result, o->radius);
ver_min (output, result, output, result, o->radius);
return TRUE;
}
static void
gegl_chant_class_init (GeglChantClass *klass)
{
GeglOperationClass *operation_class;
GeglOperationFilterClass *filter_class;
operation_class = GEGL_OPERATION_CLASS (klass);
filter_class = GEGL_OPERATION_FILTER_CLASS (klass);
filter_class->process = process;
operation_class->prepare = prepare;
gegl_operation_class_set_keys (operation_class,
"name" , "gegl:box-min",
"categories" , "misc",
"description" ,
_("Sets the target pixel to the value of the minimum value in a box surrounding the pixel"),
NULL);
}
#endif