median.hh 5.71 KB
Newer Older
Thierry Geraud's avatar
Thierry Geraud committed
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
// Copyright (C) 2007 EPITA Research and Development Laboratory
//
// This file is part of the Olena Library.  This library is free
// software; you can redistribute it and/or modify it under the terms
// of the GNU General Public License version 2 as published by the
// Free Software Foundation.
//
// This library 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 library; see the file COPYING.  If not, write to
// the Free Software Foundation, 51 Franklin Street, Fifth Floor,
// Boston, MA 02111-1307, USA.
//
// As a special exception, you may use this file as part of a free
// software library without restriction.  Specifically, if other files
// instantiate templates or use macros or inline functions from this
// file, or you compile this file and link it with other files to
// produce an executable, this file does not by itself cause the
// resulting executable to be covered by the GNU General Public
// License.  This exception does not however invalidate any other
// reasons why the executable file might be covered by the GNU General
// Public License.

#ifndef MLN_LEVEL_MEDIAN_HH
# define MLN_LEVEL_MEDIAN_HH

/*! \file mln/level/median.hh
 *
33
 * \brief Median filtering of an image.
Thierry Geraud's avatar
Thierry Geraud committed
34
35
36
 */

# include <mln/core/concept/image.hh>
37

Thierry Geraud's avatar
Thierry Geraud committed
38
# include <mln/core/window2d.hh>
39
# include <mln/core/hline2d.hh>
Thierry Geraud's avatar
Thierry Geraud committed
40

41
# include <mln/accu/median.hh>
Thierry Geraud's avatar
Thierry Geraud committed
42
43
# include <mln/canvas/sbrowsing.hh>

Thierry Geraud's avatar
Thierry Geraud committed
44
45
46
47
48
49
50

namespace mln
{

  namespace level
  {

51
52
    /*! Compute in \p output the median filter of image \p input by
     *  the window \p win.
Thierry Geraud's avatar
Thierry Geraud committed
53
54
55
56
57
     *
     * \param[in] input The image to be filtered.
     * \param[in] win The window.
     * \param[in,out] output The output image.
     *
58
     * \pre \p input and \p output have to be initialized.
Thierry Geraud's avatar
Thierry Geraud committed
59
60
61
62
63
64
65
66
67
68
69
70
     */
    template <typename I, typename W, typename O>
    void median(const Image<I>& input, const Window<W>& win,
		Image<O>& output);


# ifndef MLN_INCLUDE_ONLY


    namespace impl
    {

Thierry Geraud's avatar
Thierry Geraud committed
71
72
73
74
75
76
77
78
79
80
81
82

      template <typename I, typename W, typename O>
      struct median_functor
      { 
	// i/o

	const I& input;
	const W& win;
	O& output;

	// aux data

83
	accu::median<mln_vset(I)> med;
Thierry Geraud's avatar
Thierry Geraud committed
84
85
86
87
88
89
	mln_point(I) p;
	window2d     win_fp, win_fm, win_bp, win_bm, win_dp, win_dm;
	mln_qiter(W)   q_fp,   q_fm,   q_bp,   q_bm,   q_dp,   q_dm;

	// ctor

90
	median_functor(const I& input_, const W& win_, O& output_)
Thierry Geraud's avatar
Thierry Geraud committed
91
92
93
94
95
96
	  :
	  // i/o
	  input(exact(input_)),
	  win(exact(win_)),
	  output(exact(output_)),
	  // aux data
97
	  med(input.values()),
Thierry Geraud's avatar
Thierry Geraud committed
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
	  p(),
	  win_fp(win - (win + left)),   win_fm((win + left)  - win),
	  win_bp(win - (win + right)),  win_bm((win + right) - win),
	  win_dp(win - (win + up)),     win_dm((win + up)    - win),
	  q_fp(win_fp, p),  q_fm(win_fm, p),
	  q_bp(win_bp, p),  q_bm(win_bm, p),
	  q_dp(win_dp, p),  q_dm(win_dm, p)
	{
	}

	// parts

	void init()
	{
	  med.init();
	  mln_qiter(W) q(win, p);
	  for_all(q) if (input.has(q))
	    med.take(input(q));
	}

	void down()
	{
	  for_all(q_dm) if (input.has(q_dm))
	    med.untake(input(q_dm));
	  for_all(q_dp) if (input.has(q_dp))
	    med.take(input(q_dp));
	  output(p) = med;
	}

	void fwd()
	{
	  for_all(q_fm) if (input.has(q_fm))
	    med.untake(input(q_fm));
	  for_all(q_fp) if (input.has(q_fp))
	    med.take(input(q_fp));
	  output(p) = med;
	}

	void bkd()
	{
	  for_all(q_bm) if (input.has(q_bm))
	    med.untake(input(q_bm));
	  for_all(q_bp) if (input.has(q_bp))
	    med.take(input(q_bp));
	  output(p) = med;
	}

      }; // end of median_functor


148
149


Thierry Geraud's avatar
Thierry Geraud committed
150
      template <typename I, typename W, typename O>
151
      void median(const I& input, const Window<W>& win, O& output)
Thierry Geraud's avatar
Thierry Geraud committed
152
153
      {
	// FIXME: resize border!
154
	impl::median_functor<I,W,O> f(input, exact(win), output);
Thierry Geraud's avatar
Thierry Geraud committed
155
156
157
158
	canvas::sbrowsing(f);
      }


159
160
161
162
163


      template <typename I, typename O>
      void median(const I& input, const hline2d& win, O& output)
      {
164
165
	typedef mln_coord(I) coord;
	const coord
166
167
168
	  max_row = input.max_row(),
	  min_col = input.min_col(),
	  max_col = input.max_col();
169
	const coord half = win.length() / 2;
170
171

	point2d p;
172
173
	coord& row = p.row();
	coord& col = p.col();
174

175
	accu::median<mln_vset(I)> med(input.values());
176
177
178

	for (row = input.min_row(); row <= max_row; ++row)
	  {
179
	    coord ct, cu;
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221

	    // initialization (before first point of the row)
	    med.init();
	    for (ct = min_col; ct < min_col + half; ++ct)
	      med.take(input.at(row, ct));

	    // left columns (just take new points)
	    for (col = min_col; col <= min_col + half; ++col, ++ct)
	      {
		med.take(input.at(row, ct));
		output(p) = med;
	      }
	    
	    // middle columns (both take and untake)
	    cu = min_col;
	    for (; col <= max_col - half; ++cu, ++col, ++ct)
	      {
		med.take(input.at(row, ct));
		med.untake(input.at(row, cu));
		output(p) = med;
	      }

	    // right columns (now just untake old points)
	    for (; col <= max_col; ++cu, ++col)
	      {
		med.untake(input.at(row, cu));
		output(p) = med;
	      }
	  }
      }


      // FIXME: Use transpose.

//       template <typename I, typename O>
//       void median(const I& input, const vline2d& win, O& output)
//       {

// 	median(, hline2d(win.length()), output);
//       }


Thierry Geraud's avatar
Thierry Geraud committed
222
223
224
225
226
227
228
229
230
    } // end of namespace mln::level::impl


    // facade

    template <typename I, typename W, typename O>
    void median(const Image<I>& input, const Window<W>& win,
		Image<O>& output)
    {
231
      mln_assertion(exact(output).domain() == exact(input).domain());
Thierry Geraud's avatar
Thierry Geraud committed
232
233
234
235
236
237
238
239
240
241
242
      impl::median(exact(input), exact(win), exact(output)); 
    }

# endif // ! MLN_INCLUDE_ONLY

  } // end of namespace mln::level

} // end of namespace mln


#endif // ! MLN_LEVEL_MEDIAN_HH