// // Copyright 2005-2007 Adobe Systems Incorporated // // Distributed under 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 // #ifndef BOOST_GIL_PACKED_PIXEL_HPP #define BOOST_GIL_PACKED_PIXEL_HPP #include <boost/gil/pixel.hpp> #include <boost/gil/detail/mp11.hpp> #include <functional> #include <type_traits> namespace boost { namespace gil { /// A model of a heterogeneous pixel whose channels are bit ranges. /// For example 16-bit RGB in '565' format. /// \defgroup ColorBaseModelPackedPixel packed_pixel /// \ingroup ColorBaseModel /// \brief A heterogeneous color base whose elements are reference proxies to channels in a pixel. Models ColorBaseValueConcept. This class is used to model packed pixels, such as 16-bit packed RGB. /// \defgroup PixelModelPackedPixel packed_pixel /// \ingroup PixelModel /// \brief A heterogeneous pixel used to represent packed pixels with non-byte-aligned channels. Models PixelValueConcept /// /// Example: /// \code /// using rgb565_pixel_t = packed_pixel_type<uint16_t, mp11::mp_list-c<unsigned,5,6,5>, rgb_layout_t>::type; /// static_assert(sizeof(rgb565_pixel_t) == 2, ""); /// /// rgb565_pixel_t r565; /// get_color(r565,red_t()) = 31; /// get_color(r565,green_t()) = 63; /// get_color(r565,blue_t()) = 31; /// assert(r565 == rgb565_pixel_t((uint16_t)0xFFFF)); /// \endcode /// \ingroup ColorBaseModelPackedPixel PixelModelPackedPixel PixelBasedModel /// \brief Heterogeneous pixel value whose channel references can be constructed from the pixel bitfield and their index. Models ColorBaseValueConcept, PixelValueConcept, PixelBasedConcept /// Typical use for this is a model of a packed pixel (like 565 RGB) /// \tparam BitField Type that holds the bits of the pixel. Typically an integral type, like std::uint16_t. /// \tparam ChannelRefs MP11 list whose elements are packed channels. They must be constructible from BitField. GIL uses packed_channel_reference /// \tparam Layout defining the color space and ordering of the channels. Example value: rgb_layout_t template <typename BitField, typename ChannelRefs, typename Layout> struct packed_pixel { BitField _bitfield{0}; // TODO: Make private using layout_t = Layout; using value_type = packed_pixel<BitField, ChannelRefs, Layout>; using reference = value_type&; using const_reference = value_type const&; static constexpr bool is_mutable = channel_traits<mp11::mp_front<ChannelRefs>>::is_mutable; packed_pixel() = default; explicit packed_pixel(const BitField& bitfield) : _bitfield(bitfield) {} // Construct from another compatible pixel type packed_pixel(const packed_pixel& p) : _bitfield(p._bitfield) {} template <typename Pixel> packed_pixel(Pixel const& p, typename std::enable_if<is_pixel<Pixel>::value>::type* /*dummy*/ = nullptr) { check_compatible<Pixel>(); static_copy(p, *this); } packed_pixel(int chan0, int chan1) : _bitfield(0) { static_assert(num_channels<packed_pixel>::value == 2, ""); gil::at_c<0>(*this) = chan0; gil::at_c<1>(*this) = chan1; } packed_pixel(int chan0, int chan1, int chan2) : _bitfield(0) { static_assert(num_channels<packed_pixel>::value == 3, ""); gil::at_c<0>(*this) = chan0; gil::at_c<1>(*this) = chan1; gil::at_c<2>(*this) = chan2; } packed_pixel(int chan0, int chan1, int chan2, int chan3) : _bitfield(0) { static_assert(num_channels<packed_pixel>::value == 4, ""); gil::at_c<0>(*this) = chan0; gil::at_c<1>(*this) = chan1; gil::at_c<2>(*this) = chan2; gil::at_c<3>(*this) = chan3; } packed_pixel(int chan0, int chan1, int chan2, int chan3, int chan4) : _bitfield(0) { static_assert(num_channels<packed_pixel>::value == 5, ""); gil::at_c<0>(*this) = chan0; gil::at_c<1>(*this) = chan1; gil::at_c<2>(*this) = chan2; gil::at_c<3>(*this) = chan3; gil::at_c<4>(*this) = chan4; } auto operator=(packed_pixel const& p) -> packed_pixel& { _bitfield = p._bitfield; return *this; } template <typename Pixel> auto operator=(Pixel const& p) -> packed_pixel& { assign(p, is_pixel<Pixel>()); return *this; } template <typename Pixel> bool operator==(Pixel const& p) const { return equal(p, is_pixel<Pixel>()); } template <typename Pixel> bool operator!=(Pixel const& p) const { return !(*this==p); } private: template <typename Pixel> static void check_compatible() { gil_function_requires<PixelsCompatibleConcept<Pixel, packed_pixel>>(); } template <typename Pixel> void assign(Pixel const& p, std::true_type) { check_compatible<Pixel>(); static_copy(p, *this); } template <typename Pixel> bool equal(Pixel const& p, std::true_type) const { check_compatible<Pixel>(); return static_equal(*this, p); } // Support for assignment/equality comparison of a channel with a grayscale pixel static void check_gray() { static_assert(std::is_same<typename Layout::color_space_t, gray_t>::value, ""); } template <typename Channel> void assign(Channel const& channel, std::false_type) { check_gray(); gil::at_c<0>(*this) = channel; } template <typename Channel> bool equal (Channel const& channel, std::false_type) const { check_gray(); return gil::at_c<0>(*this) == channel; } public: auto operator=(int channel) -> packed_pixel& { check_gray(); gil::at_c<0>(*this) = channel; return *this; } bool operator==(int channel) const { check_gray(); return gil::at_c<0>(*this) == channel; } }; ///////////////////////////// // ColorBasedConcept ///////////////////////////// template <typename BitField, typename ChannelRefs, typename Layout, int K> struct kth_element_type<packed_pixel<BitField, ChannelRefs, Layout>, K> { using type = typename channel_traits<mp11::mp_at_c<ChannelRefs, K>>::value_type; }; template <typename BitField, typename ChannelRefs, typename Layout, int K> struct kth_element_reference_type<packed_pixel<BitField, ChannelRefs, Layout>, K> { using type = typename channel_traits<mp11::mp_at_c<ChannelRefs, K>>::reference; }; template <typename BitField, typename ChannelRefs, typename Layout, int K> struct kth_element_const_reference_type<packed_pixel<BitField, ChannelRefs, Layout>, K> { using type = typename channel_traits<mp11::mp_at_c<ChannelRefs, K>>::const_reference; }; template <int K, typename P, typename C, typename L> inline auto at_c(packed_pixel<P, C, L>& p) -> typename kth_element_reference_type<packed_pixel<P, C, L>, K>::type { return typename kth_element_reference_type < packed_pixel<P, C, L>, K >::type{&p._bitfield}; } template <int K, typename P, typename C, typename L> inline auto at_c(const packed_pixel<P, C, L>& p) -> typename kth_element_const_reference_type<packed_pixel<P, C, L>, K>::type { return typename kth_element_const_reference_type < packed_pixel<P, C, L>, K>::type{&p._bitfield}; } ///////////////////////////// // PixelConcept ///////////////////////////// // Metafunction predicate that flags packed_pixel as a model of PixelConcept. // Required by PixelConcept template <typename BitField, typename ChannelRefs, typename Layout> struct is_pixel<packed_pixel<BitField, ChannelRefs, Layout>> : std::true_type {}; ///////////////////////////// // PixelBasedConcept ///////////////////////////// template <typename P, typename C, typename Layout> struct color_space_type<packed_pixel<P, C, Layout>> { using type = typename Layout::color_space_t; }; template <typename P, typename C, typename Layout> struct channel_mapping_type<packed_pixel<P, C, Layout>> { using type = typename Layout::channel_mapping_t; }; template <typename P, typename C, typename Layout> struct is_planar<packed_pixel<P, C, Layout>> : std::false_type {}; //////////////////////////////////////////////////////////////////////////////// /// Support for interleaved iterators over packed pixel //////////////////////////////////////////////////////////////////////////////// /// \defgroup PixelIteratorModelPackedInterleavedPtr Pointer to packed_pixel<P,CR,Layout> /// \ingroup PixelIteratorModel /// \brief Iterators over interleaved pixels. /// The pointer packed_pixel<P,CR,Layout>* is used as an iterator over interleaved /// pixels of packed format. /// Models PixelIteratorConcept, HasDynamicXStepTypeConcept, MemoryBasedIteratorConcept template <typename P, typename C, typename L> struct iterator_is_mutable<packed_pixel<P, C, L>*> : std::integral_constant<bool, packed_pixel<P, C, L>::is_mutable> {}; template <typename P, typename C, typename L> struct iterator_is_mutable<const packed_pixel<P, C, L>*> : std::false_type {}; }} // namespace boost::gil #endif