itk::GeodesicActiveContourImageFilter< TLevelSet, TEdgeImage, TDerivImage > Class Template Reference
[Level Set-Based Segmentation Filters]

Edge based shape detection using geodesic active contours. More...

#include <itkGeodesicActiveContourImageFilter.h>

Inheritance diagram for itk::GeodesicActiveContourImageFilter:

[legend]Collaboration diagram for itk::GeodesicActiveContourImageFilter< TLevelSet, TEdgeImage, TDerivImage >:

[legend]List of all members.

Public Types
typedef GeodesicActiveContourImageFilter	Self
typedef ShapeDetectionLevelSetFilter< TLevelSet, TEdgeImage >	Superclass
typedef SmartPointer< Self >	Pointer
typedef SmartPointer< const Self >	ConstPointer
typedef LevelSetTypeDefault< TLevelSet >	LevelSetType
typedef LevelSetType::LevelSetImageType	LevelSetImageType
typedef LevelSetType::LevelSetPointer	LevelSetPointer
typedef LevelSetType::PixelType	PixelType
typedef LevelSetType::NodeType	NodeType
typedef LevelSetType::NodeContainer	NodeContainer
typedef LevelSetType::NodeContainerPointer	NodeContainerPointer
typedef TEdgeImage	EdgeImageType
typedef EdgeImageType::Pointer	EdgeImagePointer
typedef TDerivImage	DerivImageType
typedef DerivImageType::Pointer	DerivImagePointer
Public Methods
virtual const char *	GetClassName () const
	itkStaticConstMacro (SetDimension, unsigned int, TLevelSet::ImageDimension)
virtual void	SetInflationStrength (double _arg)
virtual double	GetInflationStrength ()
void	SetDerivativeImage (TDerivImage *ptr, unsigned int idx=0)
DerivImageType *	GetDerivativeImage (unsigned int idx)
Static Public Methods
Pointer	New ()
Protected Methods
	GeodesicActiveContourImageFilter ()
	~GeodesicActiveContourImageFilter ()
void	PrintSelf (std::ostream &os, Indent indent) const
virtual void	GenerateDataFull ()
virtual void	GenerateDataNarrowBand ()
virtual void	GenerateInputRequestedRegion ()

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Detailed Description

template<class TLevelSet, class TEdgeImage, class TDerivImage>
class itk::GeodesicActiveContourImageFilter< TLevelSet, TEdgeImage, TDerivImage >

Edge based shape detection using geodesic active contours.

GeodesicActiveContourImageFilter is a level set approach for boundary detection. An initial contour is evolved to minimise a weighted curve length functional, where the weight depends on the edge potential function.

The advantage of this approach over ShapeDetectionLevelSetFilter is that the evolution equation has an addition term which acts like a doublet and attracts the contour to the shape boundaries. This improves boundary detection in cases where edge features are weak.

This class requires three inputs: an initial level set, a edge potential map and the derivatives of the edge potential.

The initial level set is a floating point image which contains the initial contour as the zero level set. For example, a signed distance function from the initial front is typically used.

The edge potential image has values close to zero in regions of high image gradient and values close to one in regions with relatively constant intensity.

This class is templated on the image type which represent the level set, the type of the edge potential image and the type oft the edge potential derivatives.

This class supports narrowbanding, where at each iteration only a narrow band surrounding the propagating front is updated.

Implementation of this class is based on: "Geodesic Active Contours", V. Caselles, R. Kimmel and G. Sapiro. International Journal on Computer Vision, Vol 22, No. 1, pp 61-97, 1997

See also:

ShapeDetection

Possible improvements:

• In Caselles et al (1997) it is stated that extension of the velocities at each iteration is not required. However, this causes the level sets to bunch with near edges causing possible instabilities. Future implementation should look at including velocity extension as suggested in "Area and Length Minimizing Flows for Shape Segmentation" K. Siddiqi, Y. Lauziere, A. Tannenbaum and S. Zucker. IEEE Transaction on Image Processing Vol 7, No. 3 March 1998

• In the narrowband version, allow the user to specify the number of iterations before reinitialization.

• Add support to detect convergence.

Note: this filter will eventually be re-implemented as part of the Finite Difference Solver framework.

Definition at line 89 of file itkGeodesicActiveContourImageFilter.h.

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Member Typedef Documentation

template<class TLevelSet, class TEdgeImage, class TDerivImage> typedef SmartPointer<const Self> itk::GeodesicActiveContourImageFilter< TLevelSet, TEdgeImage, TDerivImage >::ConstPointer

Reimplemented from itk::ShapeDetectionLevelSetFilter< TLevelSet, TEdgeImage >. Definition at line 97 of file itkGeodesicActiveContourImageFilter.h.

template<class TLevelSet, class TEdgeImage, class TDerivImage> typedef DerivImageType::Pointer itk::GeodesicActiveContourImageFilter< TLevelSet, TEdgeImage, TDerivImage >::DerivImagePointer

DerivImagePointer typedef support. Definition at line 124 of file itkGeodesicActiveContourImageFilter.h.

template<class TLevelSet, class TEdgeImage, class TDerivImage> typedef TDerivImage itk::GeodesicActiveContourImageFilter< TLevelSet, TEdgeImage, TDerivImage >::DerivImageType

DerivImage typedef support. Definition at line 121 of file itkGeodesicActiveContourImageFilter.h.

template<class TLevelSet, class TEdgeImage, class TDerivImage> typedef EdgeImageType::Pointer itk::GeodesicActiveContourImageFilter< TLevelSet, TEdgeImage, TDerivImage >::EdgeImagePointer

EdgeImagePointer typedef support. Reimplemented from itk::ShapeDetectionLevelSetFilter< TLevelSet, TEdgeImage >. Definition at line 118 of file itkGeodesicActiveContourImageFilter.h.

template<class TLevelSet, class TEdgeImage, class TDerivImage> typedef TEdgeImage itk::GeodesicActiveContourImageFilter< TLevelSet, TEdgeImage, TDerivImage >::EdgeImageType

Typedef support for the EdgeImageType. Reimplemented from itk::ShapeDetectionLevelSetFilter< TLevelSet, TEdgeImage >. Definition at line 115 of file itkGeodesicActiveContourImageFilter.h.

template<class TLevelSet, class TEdgeImage, class TDerivImage> typedef LevelSetType::LevelSetImageType itk::GeodesicActiveContourImageFilter< TLevelSet, TEdgeImage, TDerivImage >::LevelSetImageType

Reimplemented from itk::ShapeDetectionLevelSetFilter< TLevelSet, TEdgeImage >. Definition at line 107 of file itkGeodesicActiveContourImageFilter.h.

template<class TLevelSet, class TEdgeImage, class TDerivImage> typedef LevelSetType::LevelSetPointer itk::GeodesicActiveContourImageFilter< TLevelSet, TEdgeImage, TDerivImage >::LevelSetPointer

Reimplemented from itk::ShapeDetectionLevelSetFilter< TLevelSet, TEdgeImage >. Definition at line 108 of file itkGeodesicActiveContourImageFilter.h.

template<class TLevelSet, class TEdgeImage, class TDerivImage> typedef LevelSetTypeDefault<TLevelSet> itk::GeodesicActiveContourImageFilter< TLevelSet, TEdgeImage, TDerivImage >::LevelSetType

Typedef support for level set related types. Reimplemented from itk::ShapeDetectionLevelSetFilter< TLevelSet, TEdgeImage >. Definition at line 106 of file itkGeodesicActiveContourImageFilter.h.

template<class TLevelSet, class TEdgeImage, class TDerivImage> typedef LevelSetType::NodeContainer itk::GeodesicActiveContourImageFilter< TLevelSet, TEdgeImage, TDerivImage >::NodeContainer

Reimplemented from itk::ShapeDetectionLevelSetFilter< TLevelSet, TEdgeImage >. Definition at line 111 of file itkGeodesicActiveContourImageFilter.h.

template<class TLevelSet, class TEdgeImage, class TDerivImage> typedef LevelSetType::NodeContainerPointer itk::GeodesicActiveContourImageFilter< TLevelSet, TEdgeImage, TDerivImage >::NodeContainerPointer

Reimplemented from itk::ShapeDetectionLevelSetFilter< TLevelSet, TEdgeImage >. Definition at line 112 of file itkGeodesicActiveContourImageFilter.h.

template<class TLevelSet, class TEdgeImage, class TDerivImage> typedef LevelSetType::NodeType itk::GeodesicActiveContourImageFilter< TLevelSet, TEdgeImage, TDerivImage >::NodeType

Reimplemented from itk::ShapeDetectionLevelSetFilter< TLevelSet, TEdgeImage >. Definition at line 110 of file itkGeodesicActiveContourImageFilter.h.

template<class TLevelSet, class TEdgeImage, class TDerivImage> typedef LevelSetType::PixelType itk::GeodesicActiveContourImageFilter< TLevelSet, TEdgeImage, TDerivImage >::PixelType

Reimplemented from itk::ShapeDetectionLevelSetFilter< TLevelSet, TEdgeImage >. Definition at line 109 of file itkGeodesicActiveContourImageFilter.h.

template<class TLevelSet, class TEdgeImage, class TDerivImage> typedef SmartPointer<Self> itk::GeodesicActiveContourImageFilter< TLevelSet, TEdgeImage, TDerivImage >::Pointer

Reimplemented from itk::ShapeDetectionLevelSetFilter< TLevelSet, TEdgeImage >. Definition at line 96 of file itkGeodesicActiveContourImageFilter.h.

template<class TLevelSet, class TEdgeImage, class TDerivImage> typedef GeodesicActiveContourImageFilter itk::GeodesicActiveContourImageFilter< TLevelSet, TEdgeImage, TDerivImage >::Self

Standard class typedefs. Reimplemented from itk::ShapeDetectionLevelSetFilter< TLevelSet, TEdgeImage >. Definition at line 94 of file itkGeodesicActiveContourImageFilter.h.

template<class TLevelSet, class TEdgeImage, class TDerivImage> typedef ShapeDetectionLevelSetFilter<TLevelSet,TEdgeImage> itk::GeodesicActiveContourImageFilter< TLevelSet, TEdgeImage, TDerivImage >::Superclass

Reimplemented from itk::ShapeDetectionLevelSetFilter< TLevelSet, TEdgeImage >. Definition at line 95 of file itkGeodesicActiveContourImageFilter.h.

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Constructor & Destructor Documentation

template<class TLevelSet, class TEdgeImage, class TDerivImage> itk::GeodesicActiveContourImageFilter< TLevelSet, TEdgeImage, TDerivImage >::GeodesicActiveContourImageFilter (    )  [protected]

template<class TLevelSet, class TEdgeImage, class TDerivImage> itk::GeodesicActiveContourImageFilter< TLevelSet, TEdgeImage, TDerivImage >::~GeodesicActiveContourImageFilter (    )  [inline, protected]

Definition at line 150 of file itkGeodesicActiveContourImageFilter.h.

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Member Function Documentation

template<class TLevelSet, class TEdgeImage, class TDerivImage> virtual void itk::GeodesicActiveContourImageFilter< TLevelSet, TEdgeImage, TDerivImage >::GenerateDataFull (    )  [protected, virtual]

Reimplemented from itk::ShapeDetectionLevelSetFilter< TLevelSet, TEdgeImage >.

template<class TLevelSet, class TEdgeImage, class TDerivImage> virtual void itk::GeodesicActiveContourImageFilter< TLevelSet, TEdgeImage, TDerivImage >::GenerateDataNarrowBand (    )  [protected, virtual]

Reimplemented from itk::ShapeDetectionLevelSetFilter< TLevelSet, TEdgeImage >.

template<class TLevelSet, class TEdgeImage, class TDerivImage> virtual void itk::GeodesicActiveContourImageFilter< TLevelSet, TEdgeImage, TDerivImage >::GenerateInputRequestedRegion (    )  [protected, virtual]

Specify the required input region to satisfiy the output request. The default is to request for the largest possible region for any output. Subclasses should override this method if a different input size is desired. See also: ProcessObject::GenerateInputRequestedRegion() Reimplemented from itk::ShapeDetectionLevelSetFilter< TLevelSet, TEdgeImage >.

template<class TLevelSet, class TEdgeImage, class TDerivImage> virtual const char* itk::GeodesicActiveContourImageFilter< TLevelSet, TEdgeImage, TDerivImage >::GetClassName (    )  const [virtual]

Run-time type information (and related methods). Reimplemented from itk::ShapeDetectionLevelSetFilter< TLevelSet, TEdgeImage >.

template<class TLevelSet, class TEdgeImage, class TDerivImage> DerivImageType* itk::GeodesicActiveContourImageFilter< TLevelSet, TEdgeImage, TDerivImage >::GetDerivativeImage (  unsigned int    idx )

Get the input derivative images.

template<class TLevelSet, class TEdgeImage, class TDerivImage> virtual double itk::GeodesicActiveContourImageFilter< TLevelSet, TEdgeImage, TDerivImage >::GetInflationStrength (    )  [virtual]

Get the inflation strength.

template<class TLevelSet, class TEdgeImage, class TDerivImage> itk::GeodesicActiveContourImageFilter< TLevelSet, TEdgeImage, TDerivImage >::itkStaticConstMacro (  SetDimension   , unsigned    int, TLevelSet::ImageDimension    )

Determine the image dimension.

template<class TLevelSet, class TEdgeImage, class TDerivImage> Pointer itk::GeodesicActiveContourImageFilter< TLevelSet, TEdgeImage, TDerivImage >::New (    )  [static]

Method for creation through the object factory. Reimplemented from itk::ShapeDetectionLevelSetFilter< TLevelSet, TEdgeImage >.

template<class TLevelSet, class TEdgeImage, class TDerivImage> void itk::GeodesicActiveContourImageFilter< TLevelSet, TEdgeImage, TDerivImage >::PrintSelf (  std::ostream &    os, Indent    indent )  const [protected, virtual]

Methods invoked by Print() to print information about the object including superclasses. Typically not called by the user (use Print() instead) but used in the hierarchical print process to combine the output of several classes. Reimplemented from itk::ShapeDetectionLevelSetFilter< TLevelSet, TEdgeImage >.

template<class TLevelSet, class TEdgeImage, class TDerivImage> void itk::GeodesicActiveContourImageFilter< TLevelSet, TEdgeImage, TDerivImage >::SetDerivativeImage (  TDerivImage *    ptr, unsigned int    idx = 0 )

Set the input derivative images.

template<class TLevelSet, class TEdgeImage, class TDerivImage> virtual void itk::GeodesicActiveContourImageFilter< TLevelSet, TEdgeImage, TDerivImage >::SetInflationStrength (  double    _arg )  [virtual]

Set the inflation strength. The parameter control the the strength of the optional ballon force. If PropagateOutward is set to false, this controls the strength of the optional contraction force. Typically, the value is application dependent (e.g. noise level, shape complexity, intensity range). Default value 0.0.

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

• itkGeodesicActiveContourImageFilter.h

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