boost/gil/extension/toolbox/color_spaces/gray_alpha.hpp

   1 //
   2 // Copyright 2012 Andreas Pokorny
   3 //
   4 // Distributed under the Boost Software License, Version 1.0
   5 // See accompanying file LICENSE_1_0.txt or copy at
   6 // http://www.boost.org/LICENSE_1_0.txt
   7 //
   8 #ifndef BOOST_GIL_EXTENSION_TOOLBOX_COLOR_SPACES_GRAY_ALPHA_HPP
   9 #define BOOST_GIL_EXTENSION_TOOLBOX_COLOR_SPACES_GRAY_ALPHA_HPP
  10
  11 #include <boost/gil/color_convert.hpp>
  12 #include <boost/gil/gray.hpp>
  13 #include <boost/gil/typedefs.hpp>
  14
  15 #include <boost/gil/detail/mp11.hpp>
  16
  17 namespace boost{ namespace gil {
  18
  19 using gray_alpha_t = mp11::mp_list<gray_color_t,alpha_t>;
  20
  21 using gray_alpha_layout_t = layout<gray_alpha_t>;
  22 using alpha_gray_layout_t = layout<gray_alpha_layout_t, mp11::mp_list_c<int,1,0>>;
  23
  24 GIL_DEFINE_BASE_TYPEDEFS(8, uint8_t, alpha_gray)
  25 GIL_DEFINE_BASE_TYPEDEFS(8s, int8_t, alpha_gray)
  26 GIL_DEFINE_BASE_TYPEDEFS(16, uint16_t, alpha_gray)
  27 GIL_DEFINE_BASE_TYPEDEFS(16s, int16_t, alpha_gray)
  28 GIL_DEFINE_BASE_TYPEDEFS(32, uint32_t, alpha_gray)
  29 GIL_DEFINE_BASE_TYPEDEFS(32s, int32_t, alpha_gray)
  30 GIL_DEFINE_BASE_TYPEDEFS(32f, float32_t, alpha_gray)
  31
  32 GIL_DEFINE_ALL_TYPEDEFS(8, uint8_t, gray_alpha)
  33 GIL_DEFINE_ALL_TYPEDEFS(8s, int8_t, gray_alpha)
  34 GIL_DEFINE_ALL_TYPEDEFS(16, uint16_t, gray_alpha)
  35 GIL_DEFINE_ALL_TYPEDEFS(16s, int16_t, gray_alpha)
  36 GIL_DEFINE_ALL_TYPEDEFS(32, uint32_t, gray_alpha)
  37 GIL_DEFINE_ALL_TYPEDEFS(32s, int32_t, gray_alpha)
  38 GIL_DEFINE_ALL_TYPEDEFS(32f, float32_t, gray_alpha)
  39
  40 /// \ingroup ColorConvert
  41 /// \brief Gray Alpha to RGBA
  42 template <>
  43 struct default_color_converter_impl<gray_alpha_t,rgba_t> {
  44     template <typename P1, typename P2>
  45     void operator()(const P1& src, P2& dst) const {
  46         get_color(dst,red_t())  =
  47             channel_convert<typename color_element_type<P2, red_t>::type>(get_color(src,gray_color_t()));
  48         get_color(dst,green_t())=
  49             channel_convert<typename color_element_type<P2, green_t>::type>(get_color(src,gray_color_t()));
  50         get_color(dst,blue_t()) =
  51             channel_convert<typename color_element_type<P2, blue_t>::type>(get_color(src,gray_color_t()));
  52         get_color(dst,alpha_t()) =
  53             channel_convert<typename color_element_type<P2, alpha_t>::type>(get_color(src,alpha_t()));
  54     }
  55 };
  56
  57 /// \brief Gray Alpha to RGB
  58 template <>
  59 struct default_color_converter_impl<gray_alpha_t,rgb_t> {
  60     template <typename P1, typename P2>
  61     void operator()(const P1& src, P2& dst) const {
  62         get_color(dst,red_t())  =
  63             channel_convert<typename color_element_type<P2, red_t>::type>(
  64                 channel_multiply(get_color(src,gray_color_t()),get_color(src,alpha_t()) )
  65                 );
  66         get_color(dst,green_t())  =
  67             channel_convert<typename color_element_type<P2, green_t>::type>(
  68                 channel_multiply(get_color(src,gray_color_t()),get_color(src,alpha_t()) )
  69                 );
  70         get_color(dst,blue_t())  =
  71             channel_convert<typename color_element_type<P2, blue_t>::type>(
  72                 channel_multiply(get_color(src,gray_color_t()),get_color(src,alpha_t()) )
  73                 );
  74     }
  75 };
  76
  77 /// \brief Gray Alpha to Gray
  78 template <>
  79 struct default_color_converter_impl<gray_alpha_t,gray_t> {
  80     template <typename P1, typename P2>
  81     void operator()(const P1& src, P2& dst) const {
  82         get_color(dst,gray_color_t())  =
  83             channel_convert<typename color_element_type<P2, gray_color_t>::type>(
  84                 channel_multiply(get_color(src,gray_color_t()),get_color(src,alpha_t()) )
  85                 );
  86     }
  87 };
  88
  89 } // namespace gil
  90 } // namespace boost
  91
  92 #endif