diff options
Diffstat (limited to 'boost/gil/extension/toolbox/color_spaces/hsv.hpp')
| -rw-r--r-- | boost/gil/extension/toolbox/color_spaces/hsv.hpp | 237 |
1 files changed, 237 insertions, 0 deletions
diff --git a/boost/gil/extension/toolbox/color_spaces/hsv.hpp b/boost/gil/extension/toolbox/color_spaces/hsv.hpp new file mode 100644 index 0000000000..6e0b332c3f --- /dev/null +++ b/boost/gil/extension/toolbox/color_spaces/hsv.hpp @@ -0,0 +1,237 @@ +/* + Copyright 2012 Christian Henning + 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). +*/ + +/*************************************************************************************************/ + +#ifndef BOOST_GIL_EXTENSION_TOOLBOX_COLOR_SPACES_HSV_HPP +#define BOOST_GIL_EXTENSION_TOOLBOX_COLOR_SPACES_HSV_HPP + +//////////////////////////////////////////////////////////////////////////////////////// +/// \file hsv.hpp +/// \brief Support for HSV color space +/// \author Christian Henning \n +/// +/// \date 2012 \n +/// +//////////////////////////////////////////////////////////////////////////////////////// + +#include <boost/numeric/conversion/cast.hpp> + +#include <boost/gil/typedefs.hpp> + +namespace boost{ namespace gil { + +/// \addtogroup ColorNameModel +/// \{ +namespace hsv_color_space +{ +/// \brief Hue +struct hue_t {}; +/// \brief Saturation +struct saturation_t{}; +/// \brief Value +struct value_t {}; +} +/// \} + +/// \ingroup ColorSpaceModel +typedef mpl::vector3< hsv_color_space::hue_t + , hsv_color_space::saturation_t + , hsv_color_space::value_t + > hsv_t; + +/// \ingroup LayoutModel +typedef layout<hsv_t> hsv_layout_t; + +GIL_DEFINE_ALL_TYPEDEFS(32f, float32_t, hsv) + +/// \ingroup ColorConvert +/// \brief RGB to HSV +template <> +struct default_color_converter_impl< rgb_t, hsv_t > +{ + template <typename P1, typename P2> + void operator()( const P1& src, P2& dst ) const + { + using namespace hsv_color_space; + + // only float32_t for hsv is supported + float32_t temp_red = channel_convert<float32_t>( get_color( src, red_t() )); + float32_t temp_green = channel_convert<float32_t>( get_color( src, green_t() )); + float32_t temp_blue = channel_convert<float32_t>( get_color( src, blue_t() )); + + float32_t hue, saturation, value; + + float32_t min_color = (std::min)( temp_red, (std::min)( temp_green, temp_blue )); + float32_t max_color = (std::max)( temp_red, (std::max)( temp_green, temp_blue )); + + value = max_color; + + float32_t diff = max_color - min_color; + + if( max_color < 0.0001f ) + { + saturation = 0.f; + } + else + { + saturation = diff / max_color; + } + + + if( saturation < 0.0001f ) + { + //it doesn't matter what value it has + hue = 0.f; + } + else + { + if( (std::abs)( boost::numeric_cast<float32_t>(temp_red - max_color) ) < 0.0001f ) + { + hue = ( temp_green - temp_blue ) + / diff; + } + else if( temp_green == max_color ) + { + hue = 2.f + ( temp_blue - temp_red ) + / diff; + } + else + { + hue = 4.f + ( temp_red - temp_green ) + / diff; + } + + //to bring it to a number between 0 and 1 + hue /= 6.f; + + if( hue < 0.f ) + { + hue++; + } + } + + get_color( dst, hue_t() ) = hue; + get_color( dst, saturation_t() ) = saturation; + get_color( dst, value_t() ) = value; + } +}; + +/// \ingroup ColorConvert +/// \brief HSV to RGB +template <> +struct default_color_converter_impl<hsv_t,rgb_t> +{ + template <typename P1, typename P2> + void operator()( const P1& src, P2& dst) const + { + using namespace hsv_color_space; + + float32_t red, green, blue; + + //If saturation is 0, the color is a shade of gray + if( abs( get_color( src, saturation_t() )) < 0.0001f ) + { + // If saturation is 0, the color is a shade of gray + red = get_color( src, value_t() ); + green = get_color( src, value_t() ); + blue = get_color( src, value_t() ); + } + else + { + float32_t frac, p, q, t, h; + uint32_t i; + + //to bring hue to a number between 0 and 6, better for the calculations + h = get_color( src, hue_t() ); + h *= 6.f; + + i = static_cast<uint32_t>(floor(h)); + + frac = h - i; + + p = get_color( src, value_t() ) + * ( 1.f - get_color( src, saturation_t() )); + + q = get_color( src, value_t() ) + * ( 1.f - ( get_color( src, saturation_t() ) * frac )); + + t = get_color( src, value_t() ) + * ( 1.f - ( get_color( src, saturation_t() ) * ( 1.f - frac ))); + + switch( i ) + { + case 0: + { + red = get_color( src, value_t() ); + green = t; + blue = p; + + break; + } + + case 1: + { + red = q; + green = get_color( src, value_t() ); + blue = p; + + break; + } + + case 2: + { + red = p; + green = get_color( src, value_t() ); + blue = t; + + break; + } + + case 3: + { + red = p; + green = q; + blue = get_color( src, value_t() ); + + break; + } + + case 4: + { + red = t; + green = p; + blue = get_color( src, value_t() ); + + break; + } + + case 5: + { + red = get_color( src, value_t() ); + green = p; + blue = q; + + break; + } + + } + } + + get_color(dst,red_t()) = + channel_convert<typename color_element_type< P2, red_t >::type>( red ); + get_color(dst,green_t())= + channel_convert<typename color_element_type< P2, green_t >::type>( green ); + get_color(dst,blue_t()) = + channel_convert<typename color_element_type< P2, blue_t >::type>( blue ); + } +}; + +} // namespace gil +} // namespace boost + +#endif // BOOST_GIL_EXTENSION_TOOLBOX_COLOR_SPACES_HSV_HPP |