sopt::gradient_operator Namespace Reference

Functions
template<typename T >
Vector< T >	diff (const Vector< T > &x)
	Numerical derivative of 1d vector. More...
template<typename T >
Vector< T >	diff_adjoint (const Vector< T > &x)
	Numerical derivative adjoint of 1d vector. More...
template<typename T >
Vector< T >	diff2d (const Vector< T > &x, const t_int rows, const t_int cols)
	Numerical derivative of 2d image. More...
template<typename T >
Vector< T >	diff2d_adjoint (const Vector< T > &x, const t_int rows, const t_int cols)
	Numerical derivative adjoint of 2d image. More...
template<typename T >
LinearTransform< Vector< T > >	gradient_operator (const t_int rows, const t_int cols)

Function Documentation

diff()

template<typename T >

Vector<T> sopt::gradient_operator::diff

(

const Vector< T > &

x

)

Numerical derivative of 1d vector.

Definition at line 11 of file gradient_operator.h.

                                   {
  if (x.size() < 2) return Vector<T>::Zero(x.size());
  Vector<T> output = Vector<T>::Zero(x.size());
  output.segment(0, x.size() - 1) = x.segment(1, x.size() - 1) - x.segment(0, x.size() - 1);
  return output;
}

Referenced by sopt::ScalarRelativeVariation< TYPE >::operator()(), and TEST_CASE().

diff2d()

template<typename T >

Vector<T> sopt::gradient_operator::diff2d	(	const Vector< T > &	x,
		const t_int	rows,
		const t_int	cols
	)

Numerical derivative of 2d image.

Definition at line 27 of file gradient_operator.h.

                                                                         {
  Matrix<T> output = Matrix<T>::Zero(rows, 2 * cols);
  const Matrix<T> &input_image = Matrix<T>::Map(x.data(), rows, cols);
  for (Eigen::Index i(0); i < rows; i++)
    output.block(0, 0, rows, cols).row(i) = diff<T>(input_image.row(i));
  for (Eigen::Index i(0); i < cols; i++)
    output.block(0, cols, rows, cols).col(i) = diff<T>(input_image.col(i));
  return Vector<T>::Map(output.data(), output.size());
}

References cols, and rows.

Referenced by gradient_operator().

diff2d_adjoint()

template<typename T >

Vector<T> sopt::gradient_operator::diff2d_adjoint	(	const Vector< T > &	x,
		const t_int	rows,
		const t_int	cols
	)

Numerical derivative adjoint of 2d image.

Definition at line 38 of file gradient_operator.h.

                                                                                 {
  const Matrix<T> &input_image = Matrix<T>::Map(x.data(), rows, 2 * cols);
  Matrix<T> output = Matrix<T>::Zero(rows, cols);
  for (Eigen::Index i(0); i < rows; i++)
    output.row(i) += diff_adjoint<T>(input_image.block(0, 0, rows, cols).row(i));
  for (Eigen::Index i(0); i < cols; i++)
    output.col(i) += diff_adjoint<T>(input_image.block(0, cols, rows, cols).col(i));
  return Vector<T>::Map(output.data(), output.size());
}

References cols, and rows.

Referenced by gradient_operator().

diff_adjoint()

template<typename T >

Vector<T> sopt::gradient_operator::diff_adjoint

(

const Vector< T > &

x

)

Numerical derivative adjoint of 1d vector.

Definition at line 19 of file gradient_operator.h.

                                           {
  Vector<T> output = Vector<T>::Zero(x.size());
  output.segment(0, x.size() - 1) -= x.segment(0, x.size() - 1);
  if (output.size() > 2) output.segment(1, x.size() - 1) = x.segment(0, x.size() - 1);
  return output;
}

gradient_operator()

template<typename T >

LinearTransform<Vector<T> > sopt::gradient_operator::gradient_operator	(	const t_int	rows,
		const t_int	cols
	)

Definition at line 48 of file gradient_operator.h.

                                                                                 {
  return LinearTransform<Vector<T>>(
      [rows, cols](Vector<T> &out, Vector<T> const &x) {
        assert(x.size() == rows * cols * 2);
        out = diff2d_adjoint(x, rows, cols) / 2.;
        assert(out.size() == rows * cols);
      },
      {{0, 1, static_cast<t_int>(rows * cols)}},
      [rows, cols](Vector<T> &out, Vector<T> const &x) {
        assert(x.size() == rows * cols);
        out = diff2d(x, rows, cols) / 2.;
        assert(out.size() == 2 * rows * cols);
      },
      {{0, 1, static_cast<t_int>(2 * rows * cols)}});
}

References cols, diff2d(), diff2d_adjoint(), and rows.