itk::IsotropicFourthOrderLevelSetImageFilter< TInputImage, TOutputImage > Class Template Reference

This class implements the 4th-order level set isotropic diffusion (smoothing) PDE. More...

#include <itkIsotropicFourthOrderLevelSetImageFilter.h>

Inheritance diagram for itk::IsotropicFourthOrderLevelSetImageFilter< TInputImage, TOutputImage >:

[legend]Collaboration diagram for itk::IsotropicFourthOrderLevelSetImageFilter< TInputImage, TOutputImage >:

[legend]List of all members.

Public Types
typedef IsotropicFourthOrderLevelSetImageFilter	Self
typedef SparseFieldFourthOrderLevelSetImageFilter< TInputImage, TOutputImage >	Superclass
typedef SmartPointer< Self >	Pointer
typedef SmartPointer< const Self >	ConstPointer
typedef Superclass::SparseImageType	SparseImageType
typedef LevelSetFunctionWithRefitTerm< TOutputImage, SparseImageType >	FunctionType
typedef FunctionType::RadiusType	RadiusType
Public Member Functions
virtual const char *	GetClassName () const
virtual unsigned int	GetMaxFilterIteration ()
virtual void	SetMaxFilterIteration (unsigned int _arg)
Static Public Member Functions
Pointer	New ()
Protected Member Functions
	IsotropicFourthOrderLevelSetImageFilter ()
	~IsotropicFourthOrderLevelSetImageFilter ()
virtual void	PrintSelf (std::ostream &os, Indent indent) const
virtual bool	Halt ()
Protected Attributes
FunctionType::Pointer	m_Function
unsigned int	m_MaxFilterIteration

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Detailed Description

template<class TInputImage, class TOutputImage>
class itk::IsotropicFourthOrderLevelSetImageFilter< TInputImage, TOutputImage >

This class implements the 4th-order level set isotropic diffusion (smoothing) PDE.

INPUT and OUTPUT

This is a volume to volume filter; however, it is meant to process (smooth) surfaces. The input surface is an isosurface of the input volume. The isosurface value to be processed can be set by calling SetIsoSurfaceValue (default is 0). The output surface is the 0-isosurface of the output volume, regardless of the input isosurface value. To visualize the input/output surfaces to this filter a mesh extraction method such as marching cubes can be used.

The 4th-order level set PDE framework is proposed as an alternative to 2nd order PDEs. By order we mean the order of differentiation of the level set image function required to compute derivatives for updating the image. For instance, the popular curvature flow uses 2nd-order derivatives of the level set image; hence, it is a 2nd order PDE.

2nd-order curvature flow can be used by itself to smooth surfaces as a post-processing filter or it can be used with other PDE terms such as a Canny edge term that attracts the surface to strong edges in a data image. Curvature flow smoothes surfaces by making the surface move in the direction that will decrease surface area.

The 4th-order PDE framework provides an improvement over curvature flow. Instead of making the surface move to decrease surface area it makes the surface move to decrease total curvature. Similar to curvature flow, these PDEs can be used alone or in conjunction with data terms. The 4th-order PDE framework is implemented in SparseFieldFourthOrderLevelSetImageFilter. This filter class, which is derived from that, uses the 4th-order PDE by itself to implement an isotropic surface smoothing algorithm. A feature preserving anisotropic variant of this algorithm is implemented in AnisotropicFourthOrderLevelSetImageFilter.

PARAMETERS

As mentioned before, the IsoSurfaceValue parameter chooses which isosurface of the input to process. The MaxFilterIterations parameter determine the number of iterations for which this filter will run. The more iterations, the more smoothing.

Definition at line 73 of file itkIsotropicFourthOrderLevelSetImageFilter.h.

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Member Typedef Documentation

template<class TInputImage, class TOutputImage> typedef SmartPointer<const Self> itk::IsotropicFourthOrderLevelSetImageFilter< TInputImage, TOutputImage >::ConstPointer

Reimplemented from itk::SparseFieldFourthOrderLevelSetImageFilter< TInputImage, TOutputImage >. Definition at line 83 of file itkIsotropicFourthOrderLevelSetImageFilter.h.

template<class TInputImage, class TOutputImage> typedef LevelSetFunctionWithRefitTerm<TOutputImage,SparseImageType> itk::IsotropicFourthOrderLevelSetImageFilter< TInputImage, TOutputImage >::FunctionType

The level set function class with a refit term that forces the curvature of the moving front to match a prescribed curvature image. Definition at line 97 of file itkIsotropicFourthOrderLevelSetImageFilter.h.

template<class TInputImage, class TOutputImage> typedef SmartPointer<Self> itk::IsotropicFourthOrderLevelSetImageFilter< TInputImage, TOutputImage >::Pointer

Reimplemented from itk::SparseFieldFourthOrderLevelSetImageFilter< TInputImage, TOutputImage >. Definition at line 82 of file itkIsotropicFourthOrderLevelSetImageFilter.h.

template<class TInputImage, class TOutputImage> typedef FunctionType::RadiusType itk::IsotropicFourthOrderLevelSetImageFilter< TInputImage, TOutputImage >::RadiusType

The radius type for the neighborhoods. Definition at line 100 of file itkIsotropicFourthOrderLevelSetImageFilter.h.

template<class TInputImage, class TOutputImage> typedef IsotropicFourthOrderLevelSetImageFilter itk::IsotropicFourthOrderLevelSetImageFilter< TInputImage, TOutputImage >::Self

Standard class typedefs Reimplemented from itk::SparseFieldFourthOrderLevelSetImageFilter< TInputImage, TOutputImage >. Definition at line 79 of file itkIsotropicFourthOrderLevelSetImageFilter.h.

template<class TInputImage, class TOutputImage> typedef Superclass::SparseImageType itk::IsotropicFourthOrderLevelSetImageFilter< TInputImage, TOutputImage >::SparseImageType

The sparse image type used in LevelSetFunctionWithRefitTerm Reimplemented from itk::SparseFieldFourthOrderLevelSetImageFilter< TInputImage, TOutputImage >. Definition at line 93 of file itkIsotropicFourthOrderLevelSetImageFilter.h.

template<class TInputImage, class TOutputImage> typedef SparseFieldFourthOrderLevelSetImageFilter<TInputImage, TOutputImage> itk::IsotropicFourthOrderLevelSetImageFilter< TInputImage, TOutputImage >::Superclass

Reimplemented from itk::SparseFieldFourthOrderLevelSetImageFilter< TInputImage, TOutputImage >. Definition at line 81 of file itkIsotropicFourthOrderLevelSetImageFilter.h.

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Constructor & Destructor Documentation

template<class TInputImage, class TOutputImage> itk::IsotropicFourthOrderLevelSetImageFilter< TInputImage, TOutputImage >::IsotropicFourthOrderLevelSetImageFilter (   )  [protected]

template<class TInputImage, class TOutputImage> itk::IsotropicFourthOrderLevelSetImageFilter< TInputImage, TOutputImage >::~IsotropicFourthOrderLevelSetImageFilter (   )  [inline, protected]

Definition at line 107 of file itkIsotropicFourthOrderLevelSetImageFilter.h.

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Member Function Documentation

template<class TInputImage, class TOutputImage> virtual const char* itk::IsotropicFourthOrderLevelSetImageFilter< TInputImage, TOutputImage >::GetClassName (   )  const [virtual]

Run-time type information (and related methods) Reimplemented from itk::SparseFieldFourthOrderLevelSetImageFilter< TInputImage, TOutputImage >.

template<class TInputImage, class TOutputImage> virtual unsigned int itk::IsotropicFourthOrderLevelSetImageFilter< TInputImage, TOutputImage >::GetMaxFilterIteration (   )  [virtual]

template<class TInputImage, class TOutputImage> virtual bool itk::IsotropicFourthOrderLevelSetImageFilter< TInputImage, TOutputImage >::Halt (   )  [inline, protected, virtual]

This filter halts when the iteration count reaches the specified count. Reimplemented from itk::FiniteDifferenceImageFilter< TInputImage, TOutputImage >. Definition at line 117 of file itkIsotropicFourthOrderLevelSetImageFilter.h.

template<class TInputImage, class TOutputImage> Pointer itk::IsotropicFourthOrderLevelSetImageFilter< TInputImage, TOutputImage >::New (   )  [static]

Standard new macro Reimplemented from itk::SparseFieldLevelSetImageFilter< TInputImage, TOutputImage >.

template<class TInputImage, class TOutputImage> virtual void itk::IsotropicFourthOrderLevelSetImageFilter< TInputImage, TOutputImage >::PrintSelf (  std::ostream &  os, Indent  indent )  const [protected, virtual]

This method first calls the Superclass InitializeIteration method. Then it determines whether ProcessNormals should be called. Reimplemented from itk::SparseFieldFourthOrderLevelSetImageFilter< TInputImage, TOutputImage >.

template<class TInputImage, class TOutputImage> virtual void itk::IsotropicFourthOrderLevelSetImageFilter< TInputImage, TOutputImage >::SetMaxFilterIteration (  unsigned int  _arg  )  [virtual]

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Member Data Documentation

template<class TInputImage, class TOutputImage> FunctionType::Pointer itk::IsotropicFourthOrderLevelSetImageFilter< TInputImage, TOutputImage >::m_Function [protected]

The LevelSetFunctionWithRefitTerm object. Definition at line 111 of file itkIsotropicFourthOrderLevelSetImageFilter.h.

template<class TInputImage, class TOutputImage> unsigned int itk::IsotropicFourthOrderLevelSetImageFilter< TInputImage, TOutputImage >::m_MaxFilterIteration [protected]

The number of iterations for which this filter will run. Definition at line 114 of file itkIsotropicFourthOrderLevelSetImageFilter.h.

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The documentation for this class was generated from the following file:

• itkIsotropicFourthOrderLevelSetImageFilter.h

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