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kernel.hpp
//
// Copyright 2005-2007 Adobe Systems Incorporated
// Copyright 2019 Miral Shah <miralshah2211@gmail.com>
// Copyright 2022 Pranam Lashkari <plashkari628@gmail.com>
//
// 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_IMAGE_PROCESSING_KERNEL_HPP
#define BOOST_GIL_IMAGE_PROCESSING_KERNEL_HPP
#include <boost/gil/utilities.hpp>
#include <boost/gil/point.hpp>
#include <boost/assert.hpp>
#include <algorithm>
#include <array>
#include <cstddef>
#include <memory>
#include <vector>
#include <cmath>
#include <stdexcept>
namespace boost { namespace gil {
// Definitions of 1D fixed-size and variable-size kernels and related operations
namespace detail {
template <typename Core>
class kernel_1d_adaptor : public Core
{
public:
kernel_1d_adaptor() = default;
explicit kernel_1d_adaptor(std::size_t center)
: center_(center)
{
BOOST_ASSERT(center_ < this->size());
}
kernel_1d_adaptor(std::size_t size, std::size_t center)
: Core(size) , center_(center)
{
BOOST_ASSERT(this->size() > 0);
BOOST_ASSERT(center_ < this->size()); // also implies `size() > 0`
}
kernel_1d_adaptor(kernel_1d_adaptor const& other)
: Core(other), center_(other.center_)
{
BOOST_ASSERT(this->size() > 0);
BOOST_ASSERT(center_ < this->size()); // also implies `size() > 0`
}
kernel_1d_adaptor& operator=(kernel_1d_adaptor const& other)
{
Core::operator=(other);
center_ = other.center_;
return *this;
}
std::size_t left_size() const
{
BOOST_ASSERT(center_ < this->size());
return center_;
}
std::size_t right_size() const
{
BOOST_ASSERT(center_ < this->size());
return this->size() - center_ - 1;
}
auto center() -> std::size_t&
{
BOOST_ASSERT(center_ < this->size());
return center_;
}
auto center() const -> std::size_t const&
{
BOOST_ASSERT(center_ < this->size());
return center_;
}
private:
std::size_t center_{0};
};
} // namespace detail
template <typename T, typename Allocator = std::allocator<T> >
class kernel_1d : public detail::kernel_1d_adaptor<std::vector<T, Allocator>>
{
using parent_t = detail::kernel_1d_adaptor<std::vector<T, Allocator>>;
public:
kernel_1d() = default;
kernel_1d(std::size_t size, std::size_t center) : parent_t(size, center) {}
template <typename FwdIterator>
kernel_1d(FwdIterator elements, std::size_t size, std::size_t center)
: parent_t(size, center)
{
detail::copy_n(elements, size, this->begin());
}
kernel_1d(kernel_1d const& other) : parent_t(other) {}
kernel_1d& operator=(kernel_1d const& other) = default;
};
template <typename T,std::size_t Size>
class kernel_1d_fixed : public detail::kernel_1d_adaptor<std::array<T, Size>>
{
using parent_t = detail::kernel_1d_adaptor<std::array<T, Size>>;
public:
static constexpr std::size_t static_size = Size;
static_assert(static_size > 0, "kernel must have size greater than 0");
static_assert(static_size % 2 == 1, "kernel size must be odd to ensure validity at the center");
kernel_1d_fixed() = default;
explicit kernel_1d_fixed(std::size_t center) : parent_t(center) {}
template <typename FwdIterator>
explicit kernel_1d_fixed(FwdIterator elements, std::size_t center)
: parent_t(center)
{
detail::copy_n(elements, Size, this->begin());
}
kernel_1d_fixed(kernel_1d_fixed const& other) : parent_t(other) {}
kernel_1d_fixed& operator=(kernel_1d_fixed const& other) = default;
};
// TODO: This data member is odr-used and definition at namespace scope
// is required by C++11. Redundant and deprecated in C++17.
template <typename T,std::size_t Size>
constexpr std::size_t kernel_1d_fixed<T, Size>::static_size;
template <typename Kernel>
inline Kernel reverse_kernel(Kernel const& kernel)
{
Kernel result(kernel);
result.center() = kernel.right_size();
std::reverse(result.begin(), result.end());
return result;
}
namespace detail {
template <typename Core>
class kernel_2d_adaptor : public Core
{
public:
kernel_2d_adaptor() = default;
explicit kernel_2d_adaptor(std::size_t center_y, std::size_t center_x)
: center_(center_x, center_y)
{
BOOST_ASSERT(center_.y < this->size() && center_.x < this->size());
}
kernel_2d_adaptor(std::size_t size, std::size_t center_y, std::size_t center_x)
: Core(size * size), square_size(size), center_(center_x, center_y)
{
BOOST_ASSERT(this->size() > 0);
BOOST_ASSERT(center_.y < this->size() && center_.x < this->size()); // implies `size() > 0`
}
kernel_2d_adaptor(kernel_2d_adaptor const& other)
: Core(other), square_size(other.square_size), center_(other.center_.x, other.center_.y)
{
BOOST_ASSERT(this->size() > 0);
BOOST_ASSERT(center_.y < this->size() && center_.x < this->size()); // implies `size() > 0`
}
kernel_2d_adaptor& operator=(kernel_2d_adaptor const& other)
{
Core::operator=(other);
center_.y = other.center_.y;
center_.x = other.center_.x;
square_size = other.square_size;
return *this;
}
std::size_t upper_size() const
{
BOOST_ASSERT(center_.y < this->size());
return center_.y;
}
std::size_t lower_size() const
{
BOOST_ASSERT(center_.y < this->size());
return this->size() - center_.y - 1;
}
std::size_t left_size() const
{
BOOST_ASSERT(center_.x < this->size());
return center_.x;
}
std::size_t right_size() const
{
BOOST_ASSERT(center_.x < this->size());
return this->size() - center_.x - 1;
}
auto center_y() -> std::size_t&
{
BOOST_ASSERT(center_.y < this->size());
return center_.y;
}
auto center_y() const -> std::size_t const&
{
BOOST_ASSERT(center_.y < this->size());
return center_.y;
}
auto center_x() -> std::size_t&
{
BOOST_ASSERT(center_.x < this->size());
return center_.x;
}
auto center_x() const -> std::size_t const&
{
BOOST_ASSERT(center_.x < this->size());
return center_.x;
}
std::size_t size() const
{
return square_size;
}
typename Core::value_type at(std::size_t x, std::size_t y) const
{
if (x >= this->size() || y >= this->size())
{
throw std::out_of_range("Index out of range");
}
return this->begin()[y * this->size() + x];
}
protected:
std::size_t square_size{0};
private:
point<std::size_t> center_{0, 0};
};
template
<
typename T,
typename Allocator = std::allocator<T>
>
class kernel_2d : public detail::kernel_2d_adaptor<std::vector<T, Allocator>>
{
using parent_t = detail::kernel_2d_adaptor<std::vector<T, Allocator>>;
public:
kernel_2d() = default;
kernel_2d(std::size_t size,std::size_t center_y, std::size_t center_x)
: parent_t(size, center_y, center_x)
{}
template <typename FwdIterator>
kernel_2d(FwdIterator elements, std::size_t size, std::size_t center_y, std::size_t center_x)
: parent_t(static_cast<int>(std::sqrt(size)), center_y, center_x)
{
detail::copy_n(elements, size, this->begin());
}
kernel_2d(kernel_2d const& other) : parent_t(other) {}
kernel_2d& operator=(kernel_2d const& other) = default;
};
template <typename T, std::size_t Size>
class kernel_2d_fixed :
public detail::kernel_2d_adaptor<std::array<T, Size * Size>>
{
using parent_t = detail::kernel_2d_adaptor<std::array<T, Size * Size>>;
public:
static constexpr std::size_t static_size = Size;
static_assert(static_size > 0, "kernel must have size greater than 0");
static_assert(static_size % 2 == 1, "kernel size must be odd to ensure validity at the center");
kernel_2d_fixed()
{
this->square_size = Size;
}
explicit kernel_2d_fixed(std::size_t center_y, std::size_t center_x) :
parent_t(center_y, center_x)
{
this->square_size = Size;
}
template <typename FwdIterator>
explicit kernel_2d_fixed(FwdIterator elements, std::size_t center_y, std::size_t center_x)
: parent_t(center_y, center_x)
{
this->square_size = Size;
detail::copy_n(elements, Size * Size, this->begin());
}
kernel_2d_fixed(kernel_2d_fixed const& other) : parent_t(other) {}
kernel_2d_fixed& operator=(kernel_2d_fixed const& other) = default;
};
// TODO: This data member is odr-used and definition at namespace scope
// is required by C++11. Redundant and deprecated in C++17.
template <typename T, std::size_t Size>
constexpr std::size_t kernel_2d_fixed<T, Size>::static_size;
template <typename Kernel>
inline Kernel reverse_kernel_2d(Kernel const& kernel)
{
Kernel result(kernel);
result.center_x() = kernel.lower_size();
result.center_y() = kernel.right_size();
std::reverse(result.begin(), result.end());
return result;
}
template<typename T, typename Allocator>
inline kernel_2d<T, Allocator> reverse_kernel(kernel_2d<T, Allocator> const& kernel)
{
return reverse_kernel_2d(kernel);
}
template<typename T, std::size_t Size>
inline kernel_2d_fixed<T, Size> reverse_kernel(kernel_2d_fixed<T, Size> const& kernel)
{
return reverse_kernel_2d(kernel);
}
} //namespace detail
}} // namespace boost::gil
#endif
boost
defined(BOOST_NO_CXX17_HDR_MEMORY_RESOURCE)
Definition: algorithm.hpp:36
boost::gil::kernel_1d
variable-size kernel
Definition: kernel.hpp:101
boost::gil::size
Returns an integral constant type specifying the number of elements in a color base.
Definition: color_base_algorithm.hpp:42
boost::gil::detail::kernel_1d_adaptor
kernel adaptor for one-dimensional cores Core needs to provide size(),begin(),end(),...
Definition: kernel.hpp:37
boost::gil::detail::kernel_2d_fixed
static-size kernel
Definition: kernel.hpp:296
boost::gil::detail::kernel_2d
variable-size kernel
Definition: kernel.hpp:272
boost::gil::kernel_1d_fixed
static-size kernel
Definition: kernel.hpp:122