Generates the upwind gradient field of fast marching arrival times. More...

#include <itkFastMarchingUpwindGradientImageFilter.h>

Inheritance diagram for itk::FastMarchingUpwindGradientImageFilter< TLevelSet, TSpeedImage >:

Collaboration diagram for itk::FastMarchingUpwindGradientImageFilter< TLevelSet, TSpeedImage >:

Public Types
enum	{ NoTargets, OneTarget, SomeTargets, AllTargets }
typedef Superclass::AxisNodeType	AxisNodeType
typedef SmartPointer< const Self >	ConstPointer
typedef GradientImageType::Pointer	GradientImagePointer
typedef Image < GradientPixelType, itkGetStaticConstMacro(SetDimension) >	GradientImageType
typedef CovariantVector < PixelType, itkGetStaticConstMacro(SetDimension) >	GradientPixelType
typedef Superclass::IndexType	IndexType
typedef Superclass::LabelImageType	LabelImageType
typedef Superclass::LevelSetImageType	LevelSetImageType
typedef Superclass::LevelSetIndexType	LevelSetIndexType
typedef Superclass::LevelSetPointer	LevelSetPointer
typedef Superclass::LevelSetType	LevelSetType
typedef Superclass::NodeContainer	NodeContainer
typedef Superclass::NodeContainerPointer	NodeContainerPointer
typedef Superclass::NodeType	NodeType
typedef Superclass::OutputSpacingType	OutputSpacingType
typedef Superclass::PixelType	PixelType
typedef SmartPointer< Self >	Pointer
typedef Superclass::OutputPointType	PointType
typedef FastMarchingUpwindGradientImageFilter	Self
typedef Superclass::SpeedImageConstPointer	SpeedImageConstPointer
typedef Superclass::SpeedImageType	SpeedImageType
typedef FastMarchingImageFilter < TLevelSet, TSpeedImage >	Superclass
Public Member Functions
virtual ::itk::LightObject::Pointer	CreateAnother (void) const
GradientImagePointer	GetGradientImage () const
virtual const char *	GetNameOfClass () const
virtual const SizeValueType &	GetNumberOfTargets ()
NodeContainerPointer	GetReachedTargetPoints ()
virtual const double &	GetTargetOffset ()
NodeContainerPointer	GetTargetPoints ()
virtual const double &	GetTargetValue ()
virtual void	SetGenerateGradientImage (bool _arg)
virtual void	SetTargetOffset (double _arg)
void	SetTargetReachedModeToAllTargets ()
	typedef (Concept::DivisionOperators< typename TLevelSet::PixelType, double >) LevelSetDoubleDivisionOperatorsCheck
	typedef (Concept::DivisionAndAssignOperators< typename TLevelSet::PixelType, double >) LevelSetDoubleDivisionAndAssignOperatorsCheck

void	SetTargetPoints (NodeContainer *points)

virtual const bool &	GetGenerateGradientImage ()
virtual void	GenerateGradientImageOn ()
virtual void	GenerateGradientImageOff ()

virtual void	SetTargetReachedMode (int _arg)
virtual const int &	GetTargetReachedMode ()
void	SetTargetReachedModeToNoTargets ()
void	SetTargetReachedModeToOneTarget ()
void	SetTargetReachedModeToSomeTargets (SizeValueType numberOfTargets)
Static Public Member Functions
static Pointer	New ()
Static Public Attributes
static const unsigned int	SetDimension = Superclass::SetDimension
Protected Member Functions
virtual void	ComputeGradient (const IndexType &index, const LevelSetImageType output, const LabelImageType labelImage, GradientImageType *gradientImage)
void	GenerateData ()
virtual void	Initialize (LevelSetImageType *)
virtual void	UpdateNeighbors (const IndexType &index, const SpeedImageType , LevelSetImageType )

	FastMarchingUpwindGradientImageFilter ()
	~FastMarchingUpwindGradientImageFilter ()
void	PrintSelf (std::ostream &os, Indent indent) const
Private Member Functions
	FastMarchingUpwindGradientImageFilter (const Self &)
void	operator= (const Self &)
Private Attributes
bool	m_GenerateGradientImage
GradientImagePointer	m_GradientImage
SizeValueType	m_NumberOfTargets
NodeContainerPointer	m_ReachedTargetPoints
double	m_TargetOffset
NodeContainerPointer	m_TargetPoints
int	m_TargetReachedMode
double	m_TargetValue

Detailed Description

template<class TLevelSet, class TSpeedImage = Image< float, ::itk::GetImageDimension< TLevelSet >::ImageDimension >>
class itk::FastMarchingUpwindGradientImageFilter< TLevelSet, TSpeedImage >

Generates the upwind gradient field of fast marching arrival times.

This filter adds some extra functionality to its base class. While the solution T(x) of the Eikonal equation is being generated by the base class with the fast marching method, the filter generates the upwind gradient vectors of T(x), storing them in an image.

Since the Eikonal equation generates the arrival times of a wave travelling at a given speed, the generated gradient vectors can be interpreted as the slowness (1/velocity) vectors of the front (the quantity inside the modulus operator in the Eikonal equation).

Gradient vectors are computed using upwind finite differences, that is, information only propagates from points where the wavefront has already passed. This is consistent with how the fast marching method works.

One more extra feature is the possibility to define a set of Target points where the propagation stops. This can be used to avoid computing the Eikonal solution for the whole domain. The front can be stopped either when one Target point is reached or all Target points are reached. The propagation can stop after a time TargetOffset has passed since the stop condition is met. This way the solution is computed a bit downstream the Target points, so that the level sets of T(x) corresponding to the Target are smooth.

Author:: Luca Antiga Ph.D. Biomedical Technologies Laboratory, Bioengineering Deparment, Mario Negri Institute, Italy.

Definition at line 61 of file itkFastMarchingUpwindGradientImageFilter.h.