8 #ifndef BOOST_GIL_IMAGE_VIEW_HPP
9 #define BOOST_GIL_IMAGE_VIEW_HPP
11 #include <boost/gil/iterator_from_2d.hpp>
16 namespace boost {
namespace gil {
49 template <
typename Loc>
54 static const std::size_t num_dimensions=2;
55 typedef typename Loc::value_type value_type;
56 typedef typename Loc::reference reference;
57 typedef typename Loc::coord_t coord_t;
58 typedef coord_t difference_type;
59 typedef typename Loc::point_t point_t;
62 template <std::
size_t D>
struct axis {
63 typedef typename Loc::template axis<D>::coord_t coord_t;
64 typedef typename Loc::template axis<D>::iterator
iterator;
68 typedef typename const_t::reference const_reference;
69 typedef typename std::iterator_traits<iterator>::pointer pointer;
70 typedef std::reverse_iterator<iterator> reverse_iterator;
71 typedef std::size_t size_type;
74 typedef locator xy_locator;
75 typedef typename xy_locator::x_iterator x_iterator;
76 typedef typename xy_locator::y_iterator y_iterator;
77 typedef typename xy_locator::x_coord_t x_coord_t;
78 typedef typename xy_locator::y_coord_t y_coord_t;
80 template <
typename Deref>
struct add_deref {
82 static type make(
const image_view<Loc>& iv,
const Deref& d) {
return type(iv.dimensions(), Loc::template add_deref<Deref>::make(iv.pixels(),d)); }
86 template <
typename View>
image_view(
const View& iv) : _dimensions(iv.dimensions()), _pixels(iv.pixels()) {}
88 template <
typename L2>
image_view(
const point_t& sz ,
const L2& loc) : _dimensions(sz), _pixels(loc) {}
89 template <
typename L2>
image_view(coord_t width, coord_t height,
const L2& loc) : _dimensions(x_coord_t(width),y_coord_t(height)), _pixels(loc) {}
91 template <
typename View>
image_view& operator=(
const View& iv) { _pixels=iv.pixels(); _dimensions=iv.dimensions();
return *
this; }
92 image_view& operator=(
const image_view& iv) { _pixels=iv.pixels(); _dimensions=iv.dimensions();
return *
this; }
94 template <
typename View>
bool operator==(
const View& v)
const {
return pixels()==v.pixels() && dimensions()==v.dimensions(); }
95 template <
typename View>
bool operator!=(
const View& v)
const {
return !(*
this==v); }
114 bool empty()
const {
return !(width() > 0 && height() > 0); }
120 reference
front()
const {
return *begin(); }
126 reference
back()
const {
return *rbegin(); }
128 const point_t& dimensions()
const {
return _dimensions; }
129 const locator& pixels()
const {
return _pixels; }
130 x_coord_t width()
const {
return dimensions().x; }
131 y_coord_t height()
const {
return dimensions().y; }
132 std::size_t num_channels()
const {
return gil::num_channels<value_type>::value; }
133 bool is_1d_traversable()
const {
return _pixels.is_1d_traversable(width()); }
137 size_type size()
const {
return width()*height(); }
138 iterator begin()
const {
return iterator(_pixels,_dimensions.x); }
139 iterator end()
const {
return begin()+(difference_type)size(); }
140 reverse_iterator rbegin()
const {
return reverse_iterator(end()); }
141 reverse_iterator rend()
const {
return reverse_iterator(begin()); }
142 reference operator[](difference_type i)
const {
return begin()[i]; }
143 iterator at(difference_type i)
const {
return begin()+i; }
144 iterator at(
const point_t& p)
const {
return begin()+p.y*width()+p.x; }
145 iterator at(x_coord_t x, y_coord_t y)
const {
return begin()+y*width()+x; }
151 reference operator()(
const point_t& p)
const {
return _pixels(p.x,p.y); }
152 reference operator()(x_coord_t x, y_coord_t y)
const {
return _pixels(x,y); }
153 template <std::
size_t D>
typename axis<D>::iterator axis_iterator(
const point_t& p)
const {
return _pixels.template axis_iterator<D>(p); }
154 xy_locator xy_at(x_coord_t x, y_coord_t y)
const {
return _pixels+point_t(x_coord_t(x),y_coord_t(y)); }
155 locator xy_at(
const point_t& p)
const {
return _pixels+p; }
160 x_iterator x_at(x_coord_t x, y_coord_t y)
const {
return _pixels.x_at(x,y); }
161 x_iterator x_at(
const point_t& p)
const {
return _pixels.x_at(p); }
162 x_iterator row_begin(y_coord_t y)
const {
return x_at(0,y); }
163 x_iterator row_end(y_coord_t y)
const {
return x_at(width(),y); }
168 y_iterator y_at(x_coord_t x, y_coord_t y)
const {
return xy_at(x,y).y(); }
169 y_iterator y_at(
const point_t& p)
const {
return xy_at(p).y(); }
170 y_iterator col_begin(x_coord_t x)
const {
return y_at(x,0); }
171 y_iterator col_end(x_coord_t x)
const {
return y_at(x,height()); }
175 template <
typename L2>
friend class image_view;
181 template <
typename L2>
182 inline void swap(image_view<L2>& x, image_view<L2>& y) {
184 swap(x._dimensions,y._dimensions);
185 swap(x._pixels, y._pixels);
192 template <
typename L>
193 struct channel_type<image_view<L> > :
public channel_type<L> {};
195 template <
typename L>
196 struct color_space_type<image_view<L> > :
public color_space_type<L> {};
198 template <
typename L>
199 struct channel_mapping_type<image_view<L> > :
public channel_mapping_type<L> {};
201 template <
typename L>
202 struct is_planar<image_view<L> > :
public is_planar<L> {};
208 template <
typename L>
209 struct dynamic_x_step_type<image_view<L> > {
210 typedef image_view<typename dynamic_x_step_type<L>::type> type;
217 template <
typename L>
218 struct dynamic_y_step_type<image_view<L> > {
219 typedef image_view<typename dynamic_y_step_type<L>::type> type;
226 template <
typename L>
227 struct transposed_type<image_view<L> > {
228 typedef image_view<typename transposed_type<L>::type> type;
A lightweight object that interprets memory as a 2D array of pixels. Models ImageViewConcept,PixelBasedConcept,HasDynamicXStepTypeConcept,HasDynamicYStepTypeConcept,HasTransposedTypeConcept.
Definition: image_view.hpp:50
reference back() const
Returns a reference to the last element in raster order.
Definition: image_view.hpp:126
void swap(const boost::gil::packed_channel_reference< BF, FB, NB, M > x, R &y)
swap for packed_channel_reference
Definition: channel.hpp:480
bool empty() const
Returns true if the view has no elements, false otherwise.
Definition: image_view.hpp:114
Provides 1D random-access navigation to the pixels of the image. Models: PixelIteratorConcept, PixelBasedConcept, HasDynamicXStepTypeConcept.
Definition: iterator_from_2d.hpp:43
void swap(image_view< Loc > &other)
Exchanges the elements of the current view with those of other in constant time.
Definition: image_view.hpp:104
reference front() const
Returns a reference to the first element in raster order.
Definition: image_view.hpp:120