/usr/include/vigra/contourcirculator.hxx is in libvigraimpex-dev 1.10.0+dfsg-11ubuntu2.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
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 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 | /************************************************************************/
/* */
/* Copyright 1998-2002 by Ullrich Koethe */
/* */
/* This file is part of the VIGRA computer vision library. */
/* The VIGRA Website is */
/* http://hci.iwr.uni-heidelberg.de/vigra/ */
/* Please direct questions, bug reports, and contributions to */
/* ullrich.koethe@iwr.uni-heidelberg.de or */
/* vigra@informatik.uni-hamburg.de */
/* */
/* Permission is hereby granted, free of charge, to any person */
/* obtaining a copy of this software and associated documentation */
/* files (the "Software"), to deal in the Software without */
/* restriction, including without limitation the rights to use, */
/* copy, modify, merge, publish, distribute, sublicense, and/or */
/* sell copies of the Software, and to permit persons to whom the */
/* Software is furnished to do so, subject to the following */
/* conditions: */
/* */
/* The above copyright notice and this permission notice shall be */
/* included in all copies or substantial portions of the */
/* Software. */
/* */
/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND */
/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES */
/* OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND */
/* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT */
/* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, */
/* WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING */
/* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR */
/* OTHER DEALINGS IN THE SOFTWARE. */
/* */
/************************************************************************/
#ifndef VIGRA_CONTOURCIRCULATOR_HXX
#define VIGRA_CONTOURCIRCULATOR_HXX
#include "pixelneighborhood.hxx"
namespace vigra
{
/** \addtogroup ImageIteratorAdapters
*/
//@{
/********************************************************/
/* */
/* CrackContourCirculator */
/* */
/********************************************************/
/** \brief Circulator that walks around a given region.
The circulator follows the <em>crack contour</em> of a given region.
Here, a region is an 8-connected component of pixels with the same
value, such as the regions in a label image.
The crack contour is located between the inside and outside
pixels, that is "on the crack" between the region and the background.
Thus, the circulator moves from pixel corner to pixel corner. By definition,
the first corner (where the circulator was initialized) gets the
coordinate (0,0), and calls to <tt>*circulator</tt> return the distance
of the current corner to the initial one.
The circulator can be used to calculate the area of a region (in pixels):
\code
// start with a pixel within the region, whose left neighbor is outside
// (see CrackContourCirculator constructor)
ImageIterator region_anchor = ...;
int area = 0;
// calculate area from following the crack contour of the region
CrackContourCirculator<ImageIterator> crack(region_anchor);
CrackContourCirculator<ImageIterator> crackend(crack);
do
{
area += crack.diff().x * crack.pos().y -
crack.diff().y * crack.pos().x;
}
while(++crack != crackend);
area /= 2;
std::cout << "Area of region " << *region_anchor << ": " << area << std::endl;
\endcode
<b>\#include</b> \<vigra/contourcirculator.hxx\><br>
Namespace: vigra
*/
template <class IMAGEITERATOR>
class CrackContourCirculator
{
typedef NeighborhoodCirculator<IMAGEITERATOR, EightNeighborCode>
NEIGHBORHOODCIRCULATOR;
typedef typename IMAGEITERATOR::value_type label_type;
protected:
NEIGHBORHOODCIRCULATOR neighborCirc_;
label_type label_;
Point2D pos_;
CrackContourCirculator(NEIGHBORHOODCIRCULATOR const & circ)
: neighborCirc_(circ),
label_(*(circ.center())),
pos_(0, 0)
{}
public:
/** the circulator's value type
*/
typedef Point2D value_type;
/** the circulator's reference type (return type of <TT>*circ</TT>)
*/
typedef Point2D const & reference;
/** the circulator's pointer type (return type of <TT>operator-></TT>)
*/
typedef Point2D const * pointer;
/** the circulator tag
*/
typedef forward_circulator_tag iterator_category;
/** Initialize the circulator for a given region.
The image iterator <tt>in_the_region</tt> must refer
to a boundary pixel of the region to be analysed. The
direction code <tt>dir</tt> must point to a pixel outside the
region (the default assumes that the pixel left of the
given region pixel belongs to the background).
The first corner of the crack contour is the corner to the
right of this direction (i.e. the north west corner of
the region pixel, if the direction was West).
*/
CrackContourCirculator(IMAGEITERATOR const & in_the_region,
vigra::FourNeighborCode::Direction dir = vigra::FourNeighborCode::West)
: neighborCirc_(in_the_region, EightNeighborCode::code(dir)),
label_(*in_the_region),
pos_(0, 0)
{
neighborCirc_.turnLeft();
}
/** Move to the next crack corner of the contour (pre-increment).
*/
CrackContourCirculator & operator++()
{
pos_ += neighborCirc_.diff();
neighborCirc_--;
if(*neighborCirc_ == label_)
{
neighborCirc_.moveCenterToNeighbor(); // TODO: simplify moveCenterToNeighbor()s
--neighborCirc_;
}
else
{
neighborCirc_.moveCenterToNeighbor(); // jump out
neighborCirc_ += 3;
if(*neighborCirc_ == label_)
{
neighborCirc_.moveCenterToNeighbor();
neighborCirc_.turnRight();
}
else
{
neighborCirc_.moveCenterToNeighbor();
neighborCirc_.turnLeft();
neighborCirc_.moveCenterToNeighbor();
neighborCirc_.turnRight();
}
}
return *this;
}
/** Move to the next crack corner of the contour (post-increment).
*/
CrackContourCirculator operator++(int)
{
CrackContourCirculator ret(*this);
++(*this);
return ret;
}
/** equality
*/
bool operator==(CrackContourCirculator const & o) const
{
return neighborCirc_ == o.neighborCirc_;
}
/** inequality
*/
bool operator!=(CrackContourCirculator const & o) const
{
return neighborCirc_ != o.neighborCirc_;
}
/** Get the coordinate of the current corner
(relative to the first corner).
*/
reference pos() const
{ return pos_; }
/** Equivalent to pos()
*/
reference operator*() const
{ return pos_; }
/** Access member of the current coordinate.
*/
pointer operator->() const
{ return &pos_; }
/** Access pixel to the right of the crack edge (outside of
* the region bounded by the crack contour we walk on). Note
* that after operator++, the iterator can still point to the
* same pixel (looking from another direction now).
*/
IMAGEITERATOR outerPixel() const
{ return NEIGHBORHOODCIRCULATOR(neighborCirc_).turnRight().base(); }
/** Get the offset from the current corner of the contour
to the next one.
*/
Diff2D const & diff() const
{ return neighborCirc_.diff(); }
};
//@}
} // namespace vigra
#endif /* VIGRA_CONTOURCIRCULATOR_HXX */
|