| /* | |
| Copyright 2005-2007 Adobe Systems Incorporated | |
| Use, modification and distribution are subject to the Boost Software License, | |
| Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at | |
| http://www.boost.org/LICENSE_1_0.txt). | |
| See http://opensource.adobe.com/gil for most recent version including documentation. | |
| */ | |
| /*************************************************************************************************/ | |
| #ifndef GIL_IMAGE_VIEW_H | |
| #define GIL_IMAGE_VIEW_H | |
| //////////////////////////////////////////////////////////////////////////////////////// | |
| /// \file | |
| /// \brief image view class | |
| /// \author Lubomir Bourdev and Hailin Jin \n | |
| /// Adobe Systems Incorporated | |
| /// \date 2005-2007 \n Last updated on February 12, 2007 | |
| /// | |
| //////////////////////////////////////////////////////////////////////////////////////// | |
| #include <cstddef> | |
| #include <iterator> | |
| #include "gil_config.hpp" | |
| #include "iterator_from_2d.hpp" | |
| //#ifdef _MSC_VER | |
| //#pragma warning(push) | |
| //#pragma warning(disable : 4244) // conversion from 'gil::image<V,Alloc>::coord_t' to 'int', possible loss of data (visual studio compiler doesn't realize that the two types are the same) | |
| //#endif | |
| namespace boost { namespace gil { | |
| //////////////////////////////////////////////////////////////////////////////////////// | |
| /// \class image_view | |
| /// \ingroup ImageViewModel PixelBasedModel | |
| /// \brief A lightweight object that interprets memory as a 2D array of pixels. Models ImageViewConcept,PixelBasedConcept,HasDynamicXStepTypeConcept,HasDynamicYStepTypeConcept,HasTransposedTypeConcept | |
| /// | |
| /// Image view consists of a pixel 2D locator (defining the mechanism for navigating in 2D) | |
| /// and the image dimensions. | |
| /// | |
| /// Image views to images are what ranges are to STL containers. They are lightweight objects, | |
| /// that don't own the pixels. It is the user's responsibility that the underlying data remains | |
| /// valid for the lifetime of the image view. | |
| /// | |
| /// Similar to iterators and ranges, constness of views does not extend to constness of pixels. | |
| /// A const \p image_view does not allow changing its location in memory (resizing, moving) but does | |
| /// not prevent one from changing the pixels. The latter requires an image view whose value_type | |
| /// is const. | |
| /// | |
| /// Images have interfaces consistent with STL 1D random access containers, so they can be used | |
| /// directly in STL algorithms like: | |
| /// \code | |
| /// std::fill(img.begin(), img.end(), red_pixel); | |
| /// \endcode | |
| /// | |
| /// In addition, horizontal, vertical and 2D random access iterators are provided. | |
| /// | |
| /// Note also that \p image_view does not require that its element type be a pixel. It could be | |
| /// instantiated with a locator whose \p value_type models only \p Regular. In this case the image | |
| /// view models the weaker RandomAccess2DImageViewConcept, and does not model PixelBasedConcept. | |
| /// Many generic algorithms don't require the elements to be pixels. | |
| /// | |
| //////////////////////////////////////////////////////////////////////////////////////// | |
| template <typename Loc> // Models 2D Pixel Locator | |
| class image_view { | |
| public: | |
| // typedefs required by ConstRandomAccessNDImageViewConcept | |
| static const std::size_t num_dimensions=2; | |
| typedef typename Loc::value_type value_type; | |
| typedef typename Loc::reference reference; // result of dereferencing | |
| typedef typename Loc::coord_t coord_t; // 1D difference type (same for all dimensions) | |
| typedef coord_t difference_type; // result of operator-(1d_iterator,1d_iterator) | |
| typedef typename Loc::point_t point_t; | |
| typedef Loc locator; | |
| typedef image_view<typename Loc::const_t> const_t; // same as this type, but over const values | |
| template <std::size_t D> struct axis { | |
| typedef typename Loc::template axis<D>::coord_t coord_t; // difference_type along each dimension | |
| typedef typename Loc::template axis<D>::iterator iterator; // 1D iterator type along each dimension | |
| }; | |
| typedef iterator_from_2d<Loc> iterator; // 1D iterator type for each pixel left-to-right inside top-to-bottom | |
| typedef std::reverse_iterator<iterator> reverse_iterator; | |
| typedef std::size_t size_type; | |
| // typedefs required by ConstRandomAccess2DImageViewConcept | |
| typedef locator xy_locator; | |
| typedef typename xy_locator::x_iterator x_iterator; // pixel iterator along a row | |
| typedef typename xy_locator::y_iterator y_iterator; // pixel iterator along a column | |
| typedef typename xy_locator::x_coord_t x_coord_t; | |
| typedef typename xy_locator::y_coord_t y_coord_t; | |
| template <typename Deref> struct add_deref { | |
| typedef image_view<typename Loc::template add_deref<Deref>::type> type; | |
| static type make(const image_view<Loc>& iv, const Deref& d) { return type(iv.dimensions(), Loc::template add_deref<Deref>::make(iv.pixels(),d)); } | |
| }; | |
| image_view() : _dimensions(0,0) {} | |
| template <typename View> image_view(const View& iv) : _dimensions(iv.dimensions()), _pixels(iv.pixels()) {} | |
| template <typename L2> image_view(const point_t& sz , const L2& loc) : _dimensions(sz), _pixels(loc) {} | |
| 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) {} | |
| template <typename View> image_view& operator=(const View& iv) { _pixels=iv.pixels(); _dimensions=iv.dimensions(); return *this; } | |
| image_view& operator=(const image_view& iv) { _pixels=iv.pixels(); _dimensions=iv.dimensions(); return *this; } | |
| template <typename View> bool operator==(const View& v) const { return pixels()==v.pixels() && dimensions()==v.dimensions(); } | |
| template <typename View> bool operator!=(const View& v) const { return !(*this==v); } | |
| template <typename L2> friend void swap(image_view<L2>& x, image_view<L2>& y); | |
| const point_t& dimensions() const { return _dimensions; } | |
| const locator& pixels() const { return _pixels; } | |
| x_coord_t width() const { return dimensions().x; } | |
| y_coord_t height() const { return dimensions().y; } | |
| std::size_t num_channels() const { return gil::num_channels<value_type>::value; } | |
| bool is_1d_traversable() const { return _pixels.is_1d_traversable(width()); } | |
| //\{@ | |
| /// \name 1D navigation | |
| size_type size() const { return width()*height(); } | |
| iterator begin() const { return iterator(_pixels,_dimensions.x); } | |
| iterator end() const { return begin()+(difference_type)size(); } // potential performance problem! | |
| reverse_iterator rbegin() const { return reverse_iterator(end()); } | |
| reverse_iterator rend() const { return reverse_iterator(begin()); } | |
| reference operator[](difference_type i) const { return begin()[i]; } // potential performance problem! | |
| iterator at(difference_type i)const { return begin()+i; } | |
| iterator at(const point_t& p) const { return begin()+p.y*width()+p.x; } | |
| iterator at(x_coord_t x, y_coord_t y)const { return begin()+y*width()+x; } | |
| //\}@ | |
| //\{@ | |
| /// \name 2-D navigation | |
| reference operator()(const point_t& p) const { return _pixels(p.x,p.y); } | |
| reference operator()(x_coord_t x, y_coord_t y)const { return _pixels(x,y); } | |
| template <std::size_t D> typename axis<D>::iterator axis_iterator(const point_t& p) const { return _pixels.axis_iterator<D>(p); } | |
| 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)); } | |
| locator xy_at(const point_t& p) const { return _pixels+p; } | |
| //\}@ | |
| //\{@ | |
| /// \name X navigation | |
| x_iterator x_at(x_coord_t x, y_coord_t y) const { return _pixels.x_at(x,y); } | |
| x_iterator x_at(const point_t& p) const { return _pixels.x_at(p); } | |
| x_iterator row_begin(y_coord_t y) const { return x_at(0,y); } | |
| x_iterator row_end(y_coord_t y) const { return x_at(width(),y); } | |
| //\}@ | |
| //\{@ | |
| /// \name Y navigation | |
| y_iterator y_at(x_coord_t x, y_coord_t y) const { return xy_at(x,y).y(); } | |
| y_iterator y_at(const point_t& p) const { return xy_at(p).y(); } | |
| y_iterator col_begin(x_coord_t x) const { return y_at(x,0); } | |
| y_iterator col_end(x_coord_t x) const { return y_at(x,height()); } | |
| //\}@ | |
| private: | |
| template <typename L2> friend class image_view; | |
| point_t _dimensions; | |
| xy_locator _pixels; | |
| }; | |
| template <typename L2> | |
| inline void swap(image_view<L2>& x, image_view<L2>& y) { | |
| using std::swap; | |
| swap(x._dimensions,y._dimensions); | |
| swap(x._pixels, y._pixels); // TODO: Extend further | |
| } | |
| ///////////////////////////// | |
| // PixelBasedConcept | |
| ///////////////////////////// | |
| template <typename L> | |
| struct channel_type<image_view<L> > : public channel_type<L> {}; | |
| template <typename L> | |
| struct color_space_type<image_view<L> > : public color_space_type<L> {}; | |
| template <typename L> | |
| struct channel_mapping_type<image_view<L> > : public channel_mapping_type<L> {}; | |
| template <typename L> | |
| struct is_planar<image_view<L> > : public is_planar<L> {}; | |
| ///////////////////////////// | |
| // HasDynamicXStepTypeConcept | |
| ///////////////////////////// | |
| template <typename L> | |
| struct dynamic_x_step_type<image_view<L> > { | |
| typedef image_view<typename dynamic_x_step_type<L>::type> type; | |
| }; | |
| ///////////////////////////// | |
| // HasDynamicYStepTypeConcept | |
| ///////////////////////////// | |
| template <typename L> | |
| struct dynamic_y_step_type<image_view<L> > { | |
| typedef image_view<typename dynamic_y_step_type<L>::type> type; | |
| }; | |
| ///////////////////////////// | |
| // HasTransposedTypeConcept | |
| ///////////////////////////// | |
| template <typename L> | |
| struct transposed_type<image_view<L> > { | |
| typedef image_view<typename transposed_type<L>::type> type; | |
| }; | |
| } } // namespace boost::gil | |
| //#ifdef _MSC_VER | |
| //#pragma warning(pop) | |
| //#endif | |
| #endif |