#include <itkLevelSetFunction.h>

Inheritance diagram for itk::LevelSetFunction< TImageType >:

Collaboration diagram for itk::LevelSetFunction< TImageType >:

Classes
struct	GlobalDataStruct
Public Types
typedef SmartPointer< const Self >	ConstPointer
typedef Superclass::FloatOffsetType	FloatOffsetType
typedef Superclass::ImageType	ImageType
typedef Superclass::NeighborhoodScalesType	NeighborhoodScalesType
typedef Superclass::NeighborhoodType	NeighborhoodType
typedef Superclass::PixelRealType	PixelRealType
typedef Superclass::PixelType	PixelType
typedef SmartPointer< Self >	Pointer
typedef Superclass::RadiusType	RadiusType
typedef PixelType	ScalarValueType
typedef LevelSetFunction	Self
typedef FiniteDifferenceFunction < TImageType >	Superclass
typedef double	TimeStepType
typedef FixedArray < ScalarValueType, itkGetStaticConstMacro(ImageDimension) >	VectorType
Public Member Functions
virtual VectorType	AdvectionField (const NeighborhoodType &, const FloatOffsetType &, GlobalDataStruct *=0) const
virtual ScalarValueType	Compute3DMinimalCurvature (const NeighborhoodType &, const FloatOffsetType &, GlobalDataStruct *gd=0)
virtual ScalarValueType	ComputeCurvatureTerm (const NeighborhoodType &, const FloatOffsetType &, GlobalDataStruct *gd=0)
virtual TimeStepType	ComputeGlobalTimeStep (void *GlobalData) const
virtual ScalarValueType	ComputeMeanCurvature (const NeighborhoodType &, const FloatOffsetType &, GlobalDataStruct *gd=0)
virtual ScalarValueType	ComputeMinimalCurvature (const NeighborhoodType &, const FloatOffsetType &, GlobalDataStruct *gd=0)
virtual PixelType	ComputeUpdate (const NeighborhoodType &neighborhood, void *globalData, const FloatOffsetType &=FloatOffsetType(0.0))
virtual ::itk::LightObject::Pointer	CreateAnother (void) const
virtual ScalarValueType	CurvatureSpeed (const NeighborhoodType &, const FloatOffsetType &, GlobalDataStruct *=0) const
virtual void *	GetGlobalDataPointer () const
virtual const char *	GetNameOfClass () const
bool	GetUseMinimalCurvature () const
virtual void	Initialize (const RadiusType &r)
virtual ScalarValueType	LaplacianSmoothingSpeed (const NeighborhoodType &, const FloatOffsetType &, GlobalDataStruct *=0) const
virtual ScalarValueType	PropagationSpeed (const NeighborhoodType &, const FloatOffsetType &, GlobalDataStruct *=0) const
virtual void	ReleaseGlobalDataPointer (void *GlobalData) const
void	SetUseMinimalCurvature (bool b)
void	UseMinimalCurvatureOff ()
void	UseMinimalCurvatureOn ()

virtual void	SetAdvectionWeight (const ScalarValueType a)
ScalarValueType	GetAdvectionWeight () const

virtual void	SetPropagationWeight (const ScalarValueType p)
ScalarValueType	GetPropagationWeight () const

virtual void	SetCurvatureWeight (const ScalarValueType c)
ScalarValueType	GetCurvatureWeight () const

void	SetLaplacianSmoothingWeight (const ScalarValueType c)
ScalarValueType	GetLaplacianSmoothingWeight () const

void	SetEpsilonMagnitude (const ScalarValueType e)
ScalarValueType	GetEpsilonMagnitude () const
Static Public Member Functions
static double	GetMaximumCurvatureTimeStep ()
static double	GetMaximumPropagationTimeStep ()
static Pointer	New ()
static void	SetMaximumCurvatureTimeStep (double n)
static void	SetMaximumPropagationTimeStep (double n)
Static Public Attributes
static const unsigned int	ImageDimension = Superclass::ImageDimension
Protected Member Functions
	LevelSetFunction ()
void	PrintSelf (std::ostream &s, Indent indent) const
virtual	~LevelSetFunction ()
Static Protected Member Functions
static VectorType	InitializeZeroVectorConstant ()
Protected Attributes
ScalarValueType	m_AdvectionWeight
OffsetValueType	m_Center
ScalarValueType	m_CurvatureWeight
ScalarValueType	m_EpsilonMagnitude
ScalarValueType	m_PropagationWeight
bool	m_UseMinimalCurvature
OffsetValueType	m_xStride [itkGetStaticConstMacro(ImageDimension)]
std::slice	x_slice [itkGetStaticConstMacro(ImageDimension)]
Static Protected Attributes
static double	m_DT
static double	m_WaveDT
static VectorType	m_ZeroVectorConstant
ScalarValueType	m_LaplacianSmoothingWeight
	LevelSetFunction (const Self &)
void	operator= (const Self &)

Detailed Description

template<class TImageType>
class itk::LevelSetFunction< TImageType >

The LevelSetFunction class is a generic function object which can be used to create a level set method filter when combined with an appropriate finite difference image filter. (See FiniteDifferenceImageFilter.)

LevelSetFunction implements a generic level set function. This function is an expanded form of the basic equation developed in [1].

$\phi_{t} + \alpha \stackrel{\rightharpoonup}{A}(\mathbf{x})\cdot\nabla\phi + \beta P(\mathbf{x})\mid\nabla\phi\mid = \gamma Z(\mathbf{x})\kappa\mid\nabla\phi\mid$

where $\stackrel{\rightharpoonup}{A}$ is an advection term, $ P $ is a propagation (growth) term, and $ Z $ is a spatial modifier term for the mean curvature $\kappa$ . $\alpha$ , $\beta$ , and $\gamma$ are all scalar constants.

Terms in the equation above are supplied through virtual methods, which must be subclassed to complete an implementation. Terms can be eliminated from the equation by setting the corresponding constants to zero. A wide variety of level set methods can be implemented by subclassing this basic equation.

In ITK, the usual sign convention is that the INSIDE of a surface contains NEGATIVE values and the OUTSIDE of the surface contains POSITIVE values.

Warning:: You MUST call Initialize() in the constructor of subclasses of this object to set it up properly to do level-set Calculations. The argument that you pass Initialize is the radius of the neighborhood needed to perform the calculations. If your subclass does not do any additional neighborhood processing, then the default radius should be 1 in each direction.

REFERENCES

: [1] Sethian, J.A. Level Set Methods. Cambridge University Press. 1996.

Definition at line 66 of file itkLevelSetFunction.h.

Member Typedef Documentation

template<class TImageType >

typedef SmartPointer< const Self > itk::LevelSetFunction< TImageType >::ConstPointer

Reimplemented from itk::FiniteDifferenceFunction< TImageType >.

Definition at line 74 of file itkLevelSetFunction.h.

template<class TImageType >

typedef Superclass::FloatOffsetType itk::LevelSetFunction< TImageType >::FloatOffsetType

A floating point offset from an image grid location. Used for interpolation among grid values in a neighborhood.

Reimplemented from itk::FiniteDifferenceFunction< TImageType >.

Reimplemented in itk::GeodesicActiveContourShapePriorLevelSetFunction< TImageType, TFeatureImageType >, itk::GeodesicActiveContourLevelSetFunction< TImageType, TFeatureImageType >, itk::ShapeDetectionLevelSetFunction< TImageType, TFeatureImageType >, itk::CurvesLevelSetFunction< TImageType, TFeatureImageType >, itk::ShapePriorSegmentationLevelSetFunction< TImageType, TFeatureImageType >, itk::LevelSetFunctionWithRefitTerm< TImageType, TSparseImageType >, and itk::SegmentationLevelSetFunction< TImageType, TFeatureImageType >.

Definition at line 94 of file itkLevelSetFunction.h.

template<class TImageType >

typedef Superclass::ImageType itk::LevelSetFunction< TImageType >::ImageType

Extract some parameters from the image type

Reimplemented from itk::FiniteDifferenceFunction< TImageType >.

Definition at line 87 of file itkLevelSetFunction.h.

template<class TImageType >

typedef Superclass::NeighborhoodScalesType itk::LevelSetFunction< TImageType >::NeighborhoodScalesType

The type of data structure that holds the scales with which the neighborhood is weighted to properly account for spacing and neighborhood radius.

Reimplemented from itk::FiniteDifferenceFunction< TImageType >.

Reimplemented in itk::LevelSetFunctionWithRefitTerm< TImageType, TSparseImageType >.

Definition at line 93 of file itkLevelSetFunction.h.

template<class TImageType >

typedef Superclass::NeighborhoodType itk::LevelSetFunction< TImageType >::NeighborhoodType

The type of data structure that is passed to this function object to evaluate at a pixel that does not lie on a data set boundary.

Reimplemented from itk::FiniteDifferenceFunction< TImageType >.

Reimplemented in itk::GeodesicActiveContourShapePriorLevelSetFunction< TImageType, TFeatureImageType >, itk::GeodesicActiveContourLevelSetFunction< TImageType, TFeatureImageType >, itk::ShapeDetectionLevelSetFunction< TImageType, TFeatureImageType >, itk::CurvesLevelSetFunction< TImageType, TFeatureImageType >, itk::ShapePriorSegmentationLevelSetFunction< TImageType, TFeatureImageType >, itk::LevelSetFunctionWithRefitTerm< TImageType, TSparseImageType >, and itk::SegmentationLevelSetFunction< TImageType, TFeatureImageType >.

Definition at line 92 of file itkLevelSetFunction.h.

template<class TImageType >

typedef Superclass::PixelRealType itk::LevelSetFunction< TImageType >::PixelRealType

Reimplemented from itk::FiniteDifferenceFunction< TImageType >.

Reimplemented in itk::SegmentationLevelSetFunction< TImageType, TFeatureImageType >.

Definition at line 90 of file itkLevelSetFunction.h.

template<class TImageType >

typedef Superclass::PixelType itk::LevelSetFunction< TImageType >::PixelType

Reimplemented from itk::FiniteDifferenceFunction< TImageType >.

Reimplemented in itk::CurvesLevelSetFunction< TImageType, TFeatureImageType >, and itk::ShapePriorSegmentationLevelSetFunction< TImageType, TFeatureImageType >.

Definition at line 88 of file itkLevelSetFunction.h.

template<class TImageType >

typedef SmartPointer< Self > itk::LevelSetFunction< TImageType >::Pointer

Reimplemented from itk::FiniteDifferenceFunction< TImageType >.

Definition at line 73 of file itkLevelSetFunction.h.

template<class TImageType >

typedef Superclass::RadiusType itk::LevelSetFunction< TImageType >::RadiusType

Neighborhood radius type

Reimplemented from itk::FiniteDifferenceFunction< TImageType >.

Definition at line 91 of file itkLevelSetFunction.h.

template<class TImageType >

typedef PixelType itk::LevelSetFunction< TImageType >::ScalarValueType

Definition at line 89 of file itkLevelSetFunction.h.

template<class TImageType >

typedef LevelSetFunction itk::LevelSetFunction< TImageType >::Self

Standard class typedefs.

Reimplemented from itk::FiniteDifferenceFunction< TImageType >.

Definition at line 71 of file itkLevelSetFunction.h.

template<class TImageType >

typedef FiniteDifferenceFunction< TImageType > itk::LevelSetFunction< TImageType >::Superclass

Reimplemented from itk::FiniteDifferenceFunction< TImageType >.

Definition at line 72 of file itkLevelSetFunction.h.

template<class TImageType >

typedef double itk::LevelSetFunction< TImageType >::TimeStepType

Convenient typedefs.

Reimplemented from itk::FiniteDifferenceFunction< TImageType >.

Reimplemented in itk::ShapePriorSegmentationLevelSetFunction< TImageType, TFeatureImageType >, and itk::LevelSetFunctionWithRefitTerm< TImageType, TSparseImageType >.

Definition at line 86 of file itkLevelSetFunction.h.

template<class TImageType >

typedef FixedArray< ScalarValueType, itkGetStaticConstMacro(ImageDimension) > itk::LevelSetFunction< TImageType >::VectorType

The vector type that will be used in the calculations.

Reimplemented in itk::SegmentationLevelSetFunction< TImageType, TFeatureImageType >.

Definition at line 98 of file itkLevelSetFunction.h.

Constructor & Destructor Documentation

template<class TImageType >

itk::LevelSetFunction< TImageType >::LevelSetFunction ( ) [inline, protected]

Definition at line 298 of file itkLevelSetFunction.h.

template<class TImageType >

virtual itk::LevelSetFunction< TImageType >::~LevelSetFunction ( ) [inline, protected, virtual]

Definition at line 307 of file itkLevelSetFunction.h.

template<class TImageType >

itk::LevelSetFunction< TImageType >::LevelSetFunction ( const Self & ) [private]

Laplacean smoothing term

Member Function Documentation

template<class TImageType >

virtual VectorType itk::LevelSetFunction< TImageType >::AdvectionField	(	const NeighborhoodType &	,
		const FloatOffsetType &	,
		GlobalDataStruct *	= `0`
	)		const `[inline, virtual]`

Advection field. Default implementation returns a vector of zeros.

Reimplemented in itk::SegmentationLevelSetFunction< TImageType, TFeatureImageType >.

Definition at line 125 of file itkLevelSetFunction.h.

template<class TImageType >

virtual ScalarValueType itk::LevelSetFunction< TImageType >::Compute3DMinimalCurvature	(	const NeighborhoodType &	,
		const FloatOffsetType &	,
		GlobalDataStruct *	gd = `0`
	)		`[virtual]`

template<class TImageType >

virtual ScalarValueType itk::LevelSetFunction< TImageType >::ComputeCurvatureTerm	(	const NeighborhoodType &	,
		const FloatOffsetType &	,
		GlobalDataStruct *	gd = `0`
	)		`[virtual]`

template<class TImageType >

virtual TimeStepType itk::LevelSetFunction< TImageType >::ComputeGlobalTimeStep ( void * GlobalData ) const [virtual]

Computes the time step for an update given a global data structure. The data used in the computation may take different forms depending on the nature of the equations. This global data cannot be kept in the instance of the equation object itself since the equation object must remain stateless for thread safety. The global data is therefore managed for each thread by the finite difference solver filters.

Implements itk::FiniteDifferenceFunction< TImageType >.

Reimplemented in itk::LevelSetFunctionWithRefitTerm< TImageType, TSparseImageType >, and itk::ShapePriorSegmentationLevelSetFunction< TImageType, TFeatureImageType >.

template<class TImageType >

virtual ScalarValueType itk::LevelSetFunction< TImageType >::ComputeMeanCurvature	(	const NeighborhoodType &	,
		const FloatOffsetType &	,
		GlobalDataStruct *	gd = `0`
	)		`[virtual]`

template<class TImageType >

virtual ScalarValueType itk::LevelSetFunction< TImageType >::ComputeMinimalCurvature	(	const NeighborhoodType &	,
		const FloatOffsetType &	,
		GlobalDataStruct *	gd = `0`
	)		`[virtual]`

template<class TImageType >

virtual PixelType itk::LevelSetFunction< TImageType >::ComputeUpdate	(	const NeighborhoodType &	neighborhood,
		void *	globalData,
		const FloatOffsetType &	= `FloatOffsetType(0.0)`
	)		`[virtual]`

Compute the equation value.

Implements itk::FiniteDifferenceFunction< TImageType >.

Reimplemented in itk::ShapePriorSegmentationLevelSetFunction< TImageType, TFeatureImageType >.

template<class TImageType >

virtual::itk::LightObject::Pointer itk::LevelSetFunction< TImageType >::CreateAnother ( void ) const [virtual]

Create an object from an instance, potentially deferring to a factory. This method allows you to create an instance of an object that is exactly the same type as the referring object. This is useful in cases where an object has been cast back to a base class.

Reimplemented from itk::LightObject.

template<class TImageType >

virtual ScalarValueType itk::LevelSetFunction< TImageType >::CurvatureSpeed	(	const NeighborhoodType &	,
		const FloatOffsetType &	,
		GlobalDataStruct *	= `0`
	)		const `[inline, virtual]`

Curvature speed. Can be used to spatially modify the effects of curvature . The default implementation returns one.

Reimplemented in itk::GeodesicActiveContourShapePriorLevelSetFunction< TImageType, TFeatureImageType >, itk::GeodesicActiveContourLevelSetFunction< TImageType, TFeatureImageType >, itk::ShapeDetectionLevelSetFunction< TImageType, TFeatureImageType >, and itk::CurvesLevelSetFunction< TImageType, TFeatureImageType >.

Definition at line 138 of file itkLevelSetFunction.h.

template<class TImageType >

ScalarValueType itk::LevelSetFunction< TImageType >::GetAdvectionWeight ( ) const [inline]

Alpha. Scales all advection term values.

Definition at line 153 of file itkLevelSetFunction.h.

template<class TImageType >

ScalarValueType itk::LevelSetFunction< TImageType >::GetCurvatureWeight ( ) const [inline]

Gamma. Scales all curvature weight values

Definition at line 167 of file itkLevelSetFunction.h.

template<class TImageType >

ScalarValueType itk::LevelSetFunction< TImageType >::GetEpsilonMagnitude ( ) const [inline]

Epsilon.

Definition at line 181 of file itkLevelSetFunction.h.

template<class TImageType >

virtual void* itk::LevelSetFunction< TImageType >::GetGlobalDataPointer ( ) const [inline, virtual]

Returns a pointer to a global data structure that is passed to this object from the solver at each calculation. The idea is that the solver holds the state of any global values needed to calculate the time step, while the equation object performs the actual calculations. The global data should also be initialized in this method. Global data can be used for caching any values used or reused by the FunctionObject. Each thread should receive its own global data struct.

Implements itk::FiniteDifferenceFunction< TImageType >.

Reimplemented in itk::ShapePriorSegmentationLevelSetFunction< TImageType, TFeatureImageType >.

Definition at line 205 of file itkLevelSetFunction.h.

References itk::LevelSetFunction< TImageType >::GlobalDataStruct::m_MaxAdvectionChange, itk::LevelSetFunction< TImageType >::GlobalDataStruct::m_MaxCurvatureChange, and itk::LevelSetFunction< TImageType >::GlobalDataStruct::m_MaxPropagationChange.

template<class TImageType >

ScalarValueType itk::LevelSetFunction< TImageType >::GetLaplacianSmoothingWeight ( ) const [inline]

Weight of the laplacian smoothing term

Definition at line 174 of file itkLevelSetFunction.h.

template<class TImageType >

static double itk::LevelSetFunction< TImageType >::GetMaximumCurvatureTimeStep ( ) [inline, static]

Definition at line 278 of file itkLevelSetFunction.h.

template<class TImageType >

static double itk::LevelSetFunction< TImageType >::GetMaximumPropagationTimeStep ( ) [inline, static]

Definition at line 292 of file itkLevelSetFunction.h.

template<class TImageType >

virtual const char* itk::LevelSetFunction< TImageType >::GetNameOfClass ( ) const [virtual]

Run-time type information (and related methods)

Reimplemented from itk::FiniteDifferenceFunction< TImageType >.

template<class TImageType >

ScalarValueType itk::LevelSetFunction< TImageType >::GetPropagationWeight ( ) const [inline]

Beta. Scales all propagation term values.

Definition at line 160 of file itkLevelSetFunction.h.

template<class TImageType >

bool itk::LevelSetFunction< TImageType >::GetUseMinimalCurvature ( ) const [inline]

Definition at line 254 of file itkLevelSetFunction.h.

template<class TImageType >

virtual void itk::LevelSetFunction< TImageType >::Initialize ( const RadiusType & r ) [virtual]

This method creates the appropriate member variable operators for the level-set calculations. The argument to this function is a the radius necessary for performing the level-set calculations.

template<class TImageType >

static VectorType itk::LevelSetFunction< TImageType >::InitializeZeroVectorConstant ( ) [static, protected]

This method's only purpose is to initialize the zero vector constant.

template<class TImageType >

virtual ScalarValueType itk::LevelSetFunction< TImageType >::LaplacianSmoothingSpeed	(	const NeighborhoodType &	,
		const FloatOffsetType &	,
		GlobalDataStruct *	= `0`
	)		const `[inline, virtual]`

Laplacian smoothing speed. Can be used to spatially modify the effects of laplacian smoothing of the level set function

Definition at line 145 of file itkLevelSetFunction.h.

template<class TImageType >

static Pointer itk::LevelSetFunction< TImageType >::New ( ) [static]

Method for creation through the object factory.

Reimplemented from itk::LightObject.

template<class TImageType >

void itk::LevelSetFunction< TImageType >::operator= ( const Self & ) [private]

Laplacean smoothing term

Reimplemented from itk::FiniteDifferenceFunction< TImageType >.

template<class TImageType >

void itk::LevelSetFunction< TImageType >::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::FiniteDifferenceFunction< TImageType >.

Reimplemented in itk::ThresholdSegmentationLevelSetFunction< TImageType, TFeatureImageType >, itk::GeodesicActiveContourShapePriorLevelSetFunction< TImageType, TFeatureImageType >, itk::GeodesicActiveContourLevelSetFunction< TImageType, TFeatureImageType >, itk::VectorThresholdSegmentationLevelSetFunction< TImageType, TFeatureImageType >, itk::ShapePriorSegmentationLevelSetFunction< TImageType, TFeatureImageType >, itk::CurvesLevelSetFunction< TImageType, TFeatureImageType >, and itk::LevelSetFunctionWithRefitTerm< TImageType, TSparseImageType >.

template<class TImageType >

virtual ScalarValueType itk::LevelSetFunction< TImageType >::PropagationSpeed	(	const NeighborhoodType &	,
		const FloatOffsetType &	,
		GlobalDataStruct *	= `0`
	)		const `[inline, virtual]`

Propagation speed. This term controls surface expansion/contraction. Default implementation returns zero.

Reimplemented in itk::SegmentationLevelSetFunction< TImageType, TFeatureImageType >, and itk::LevelSetFunctionWithRefitTerm< TImageType, TSparseImageType >.

Definition at line 131 of file itkLevelSetFunction.h.

template<class TImageType >

virtual void itk::LevelSetFunction< TImageType >::ReleaseGlobalDataPointer ( void * GlobalData ) const [inline, virtual]

When the finite difference solver filter has finished using a global data pointer, it passes it to this method, which frees the memory. The solver cannot free the memory because it does not know the type to which the pointer points.

Implements itk::FiniteDifferenceFunction< TImageType >.

Reimplemented in itk::ShapePriorSegmentationLevelSetFunction< TImageType, TFeatureImageType >.

Definition at line 224 of file itkLevelSetFunction.h.

template<class TImageType >

virtual void itk::LevelSetFunction< TImageType >::SetAdvectionWeight ( const ScalarValueType a ) [inline, virtual]

Alpha. Scales all advection term values.

Definition at line 151 of file itkLevelSetFunction.h.

template<class TImageType >

virtual void itk::LevelSetFunction< TImageType >::SetCurvatureWeight ( const ScalarValueType c ) [inline, virtual]

Gamma. Scales all curvature weight values

Definition at line 165 of file itkLevelSetFunction.h.

template<class TImageType >

void itk::LevelSetFunction< TImageType >::SetEpsilonMagnitude ( const ScalarValueType e ) [inline]

Epsilon.

Definition at line 179 of file itkLevelSetFunction.h.

References itk::Math::e.

template<class TImageType >

void itk::LevelSetFunction< TImageType >::SetLaplacianSmoothingWeight ( const ScalarValueType c ) [inline]

Weight of the laplacian smoothing term

Definition at line 172 of file itkLevelSetFunction.h.

template<class TImageType >

static void itk::LevelSetFunction< TImageType >::SetMaximumCurvatureTimeStep ( double n ) [inline, static]

Set/Get the maximum constraint for the curvature term factor in the time step calculation. Changing this value from the default is not recommended or necessary, but can be used to speed up the surface evolution at the risk of creating an unstable solution.

Definition at line 273 of file itkLevelSetFunction.h.

Referenced by itk::SegmentationLevelSetImageFilter< TInputImage, TFeatureImage, TOutputPixelType >::SetMaximumCurvatureTimeStep().

template<class TImageType >

static void itk::LevelSetFunction< TImageType >::SetMaximumPropagationTimeStep ( double n ) [inline, static]

Set/Get the maximum constraint for the scalar/vector term factor of the time step calculation. Changing this value from the default is not recommended or necessary, but can be used to speed up the surface evolution at the risk of creating an unstable solution.

Definition at line 287 of file itkLevelSetFunction.h.

template<class TImageType >

virtual void itk::LevelSetFunction< TImageType >::SetPropagationWeight ( const ScalarValueType p ) [inline, virtual]