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CoscotFunction< T > Class Template Reference |  |
#include <vigra/resizeimage.hxx>
Public Types | |
| typedef T | argument_type |
| typedef T | result_type |
| typedef T | value_type |
Public Member Functions | |
| unsigned int | derivativeOrder () const |
| result_type | operator() (argument_type x) const |
| value_type | operator[] (value_type x) const |
| ArrayVector< double > const & | prefilterCoefficients () const |
| double | radius () const |
Detailed Description
template<class T>
class vigra::CoscotFunction< T >
The Coscot interpolation function.
Implements the Coscot interpolation function proposed by Maria Magnusson Seger (maria@isy.liu.se) in the context of tomographic reconstruction. It provides a fast transition between the pass- and stop-bands and minimal ripple outside the transition region. Both properties are important for this application and can be tuned by the parameters m and h (with defaults 3 and 0.5). The function is defined by
![\[ f_{m,h}(x) = \left\{ \begin{array}{ll} \frac{1}{2m}\sin(\pi x)\cot(\pi x / (2 m))(h + (1-h)\cos(\pi x/m)) & |x| \leq m \\ 0 & \mbox{otherwise} \end{array}\right. \]](form_86.png)
It can be used as a functor, and as a kernel for resamplingConvolveImage() to create a differentiable interpolant of an image.
#include <vigra/resizeimage.hxx>
Namespace: vigra
Member Typedef Documentation
| typedef T value_type |
the kernel's value type
| typedef T argument_type |
the unary functor's argument type
| typedef T result_type |
the splines polynomial order
Member Function Documentation
| result_type operator() | ( | argument_type | x | ) | const |
function (functor) call
| value_type operator[] | ( | value_type | x | ) | const |
index operator – same as operator()
| double radius | ( | ) | const |
Radius of the function's support. Needed for resamplingConvolveImage(), equals m.
| unsigned int derivativeOrder | ( | ) | const |
Derivative order of the function: always 0.
| ArrayVector<double> const& prefilterCoefficients | ( | ) | const |
Prefilter coefficients for compatibility with vigra::BSpline. (array has zero length, since prefiltering is not necessary).
The documentation for this class was generated from the following file:
- vigra/resizeimage.hxx