boost/gil/extension/io/png/detail/supported_types.hpp
// // Copyright 2007-2008 Christian Henning, Andreas Pokorny, Lubomir Bourdev // // 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_EXTENSION_IO_PNG_DETAIL_SUPPORTED_TYPES_HPP #define BOOST_GIL_EXTENSION_IO_PNG_DETAIL_SUPPORTED_TYPES_HPP #include <boost/gil/extension/io/png/tags.hpp> #ifdef BOOST_GIL_IO_ENABLE_GRAY_ALPHA #include <boost/gil/extension/toolbox/color_spaces/gray_alpha.hpp> #endif // BOOST_GIL_IO_ENABLE_GRAY_ALPHA #include <cstddef> #include <type_traits> namespace boost { namespace gil { namespace detail { static const size_t PNG_BYTES_TO_CHECK = 4; // Read support template< png_bitdepth::type BitDepth , png_color_type::type ColorType > struct png_rw_support_base { static const png_bitdepth::type _bit_depth = BitDepth; static const png_color_type::type _color_type = ColorType; }; template< typename Channel , typename ColorSpace > struct png_read_support : read_support_false , png_rw_support_base< 1 , PNG_COLOR_TYPE_GRAY > {}; template< typename BitField , bool Mutable > struct png_read_support< packed_dynamic_channel_reference< BitField , 1 , Mutable > , gray_t > : read_support_true , png_rw_support_base< 1 , PNG_COLOR_TYPE_GRAY > {}; template< typename BitField , bool Mutable > struct png_read_support< packed_dynamic_channel_reference< BitField , 2 , Mutable > , gray_t > : read_support_true , png_rw_support_base< 2 , PNG_COLOR_TYPE_GRAY > {}; template< typename BitField , bool Mutable > struct png_read_support< packed_dynamic_channel_reference< BitField , 4 , Mutable > , gray_t > : read_support_true , png_rw_support_base< 4 , PNG_COLOR_TYPE_GRAY > {}; template<> struct png_read_support<uint8_t , gray_t > : read_support_true , png_rw_support_base< 8 , PNG_COLOR_TYPE_GRAY > {}; #ifdef BOOST_GIL_IO_ENABLE_GRAY_ALPHA template<> struct png_read_support<uint8_t , gray_alpha_t > : read_support_true , png_rw_support_base< 8 , PNG_COLOR_TYPE_GA > {}; #endif // BOOST_GIL_IO_ENABLE_GRAY_ALPHA template<> struct png_read_support<uint8_t , rgb_t > : read_support_true , png_rw_support_base< 8 , PNG_COLOR_TYPE_RGB > {}; template<> struct png_read_support<uint8_t , rgba_t > : read_support_true , png_rw_support_base< 8 , PNG_COLOR_TYPE_RGBA > {}; template<> struct png_read_support<uint16_t , gray_t > : read_support_true , png_rw_support_base< 16 , PNG_COLOR_TYPE_GRAY > {}; template<> struct png_read_support<uint16_t , rgb_t > : read_support_true , png_rw_support_base< 16 , PNG_COLOR_TYPE_RGB > {}; template<> struct png_read_support<uint16_t , rgba_t > : read_support_true , png_rw_support_base< 16 , PNG_COLOR_TYPE_RGBA > {}; #ifdef BOOST_GIL_IO_ENABLE_GRAY_ALPHA template<> struct png_read_support<uint16_t , gray_alpha_t > : read_support_true , png_rw_support_base< 16 , PNG_COLOR_TYPE_GA > {}; #endif // BOOST_GIL_IO_ENABLE_GRAY_ALPHA // Write support template< typename Channel , typename ColorSpace > struct png_write_support : write_support_false , png_rw_support_base< 1 , PNG_COLOR_TYPE_GRAY > {}; template< typename BitField , bool Mutable > struct png_write_support< packed_dynamic_channel_reference< BitField , 1 , Mutable > , gray_t > : write_support_true , png_rw_support_base< 1 , PNG_COLOR_TYPE_GRAY > {}; template< typename BitField , bool Mutable > struct png_write_support< packed_dynamic_channel_reference< BitField , 1 , Mutable > const , gray_t > : write_support_true , png_rw_support_base< 1 , PNG_COLOR_TYPE_GRAY > {}; template< typename BitField , bool Mutable > struct png_write_support< packed_dynamic_channel_reference< BitField , 2 , Mutable > , gray_t > : write_support_true , png_rw_support_base< 2 , PNG_COLOR_TYPE_GRAY > {}; template< typename BitField , bool Mutable > struct png_write_support< packed_dynamic_channel_reference< BitField , 2 , Mutable > const , gray_t > : write_support_true , png_rw_support_base< 2 , PNG_COLOR_TYPE_GRAY > {}; template< typename BitField , bool Mutable > struct png_write_support< packed_dynamic_channel_reference< BitField , 4 , Mutable > , gray_t > : write_support_true , png_rw_support_base< 4 , PNG_COLOR_TYPE_GRAY > {}; template< typename BitField , bool Mutable > struct png_write_support< packed_dynamic_channel_reference< BitField , 4 , Mutable > const , gray_t > : write_support_true , png_rw_support_base< 4 , PNG_COLOR_TYPE_GRAY > {}; template<> struct png_write_support<uint8_t , gray_t > : write_support_true , png_rw_support_base< 8 , PNG_COLOR_TYPE_GRAY > {}; #ifdef BOOST_GIL_IO_ENABLE_GRAY_ALPHA template<> struct png_write_support<uint8_t , gray_alpha_t > : write_support_true , png_rw_support_base< 8 , PNG_COLOR_TYPE_GA > {}; #endif // BOOST_GIL_IO_ENABLE_GRAY_ALPHA template<> struct png_write_support<uint8_t , rgb_t > : write_support_true , png_rw_support_base< 8 , PNG_COLOR_TYPE_RGB > {}; template<> struct png_write_support<uint8_t , rgba_t > : write_support_true , png_rw_support_base< 8 , PNG_COLOR_TYPE_RGBA > {}; template<> struct png_write_support<uint16_t , gray_t > : write_support_true , png_rw_support_base< 16 , PNG_COLOR_TYPE_GRAY > {}; template<> struct png_write_support<uint16_t , rgb_t > : write_support_true , png_rw_support_base< 16 , PNG_COLOR_TYPE_RGB > {}; template<> struct png_write_support<uint16_t , rgba_t > : write_support_true , png_rw_support_base< 16 , PNG_COLOR_TYPE_RGBA > {}; #ifdef BOOST_GIL_IO_ENABLE_GRAY_ALPHA template<> struct png_write_support<uint16_t , gray_alpha_t > : write_support_true , png_rw_support_base< 16 , PNG_COLOR_TYPE_GA > {}; #endif // BOOST_GIL_IO_ENABLE_GRAY_ALPHA } // namespace detail template<typename Pixel> struct is_read_supported<Pixel, png_tag> : std::integral_constant < bool, detail::png_read_support < typename channel_type<Pixel>::type, typename color_space_type<Pixel>::type >::is_supported > { using parent_t = detail::png_read_support < typename channel_type<Pixel>::type, typename color_space_type<Pixel>::type >; static const png_bitdepth::type _bit_depth = parent_t::_bit_depth; static const png_color_type::type _color_type = parent_t::_color_type; }; template<typename Pixel> struct is_write_supported<Pixel, png_tag> : std::integral_constant < bool, detail::png_write_support < typename channel_type<Pixel>::type, typename color_space_type<Pixel>::type >::is_supported > { using parent_t = detail::png_write_support < typename channel_type<Pixel>::type, typename color_space_type<Pixel>::type >; static const png_bitdepth::type _bit_depth = parent_t::_bit_depth; static const png_color_type::type _color_type = parent_t::_color_type; }; } // namespace gil } // namespace boost #endif