vtkDijkstraImageGeodesicPath Class Reference

#include <vtkDijkstraImageGeodesicPath.h>

Inheritance diagram for vtkDijkstraImageGeodesicPath:

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Collaboration diagram for vtkDijkstraImageGeodesicPath:

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List of all members.

Detailed Description

Dijkstra algorithm to compute the graph geodesic.

Takes as input a polyline and an image representing a 2D cost function and performs a single source shortest path calculation. Dijkstra's algorithm is used. The implementation is similar to the one described in Introduction to Algorithms (Second Edition) by Thomas H. Cormen, Charles E. Leiserson, Ronald L. Rivest, and Cliff Stein, published by MIT Press and McGraw-Hill. Some minor enhancement are added though. All vertices are not pushed on the heap at start, instead a front set is maintained. The heap is implemented as a binary heap. The output of the filter is a set of lines describing the shortest path from StartVertex to EndVertex. See parent class vtkDijkstraGraphGeodesicPath for the implementation.

Warning:: The input cost image must have only VTK_PIXEL cells: i.e., a 2D image or slice of a 3D volume. A cost function for a gray scale image might be generated by the following pipeline: vtkImageData->vtkImageGradientMagnitude->vtkImageShiftScale wherein the gradient magnitude image is inverted so that strong edges have low cost value. Costs in moving from a vertex v to a vertex u are calculated using a weighted additive sheme: cost = Iw*f(I) + Ew*f(u,v) + Cw*f(t,u,v) where Iw is the weight associated with f(I): the normalized image cost, Ew is the weight associated with f(u,v): the normalized distance between vertices u and v, and Cw is the weight associated with f(t,u,v): the normalized curvature calculated from the vertex t which precedes vertex u, and vertices u and v. All weights range from 0 to 1.

Thanks:: The class was contributed by Dean Inglis.

Tests:: vtkDijkstraImageGeodesicPath (Tests)

Definition at line 59 of file vtkDijkstraImageGeodesicPath.h.


typedef vtkDijkstraGraphGeodesicPath	Superclass
static int	IsTypeOf (const char *type)
static vtkDijkstraImageGeodesicPath *	SafeDownCast (vtkObject *o)
virtual const char *	GetClassName ()
virtual int	IsA (const char *type)
void	PrintSelf (ostream &os, vtkIndent indent)
Public Member Functions

void	SetInput (vtkDataObject *)
vtkImageData *	GetInputAsImageData ()

void	SetImageWeight (double)
virtual double	GetImageWeight ()

void	SetEdgeLengthWeight (double)
virtual double	GetEdgeLengthWeight ()

virtual void	SetCurvatureWeight (double)
virtual double	GetCurvatureWeight ()
Static Public Member Functions
static vtkDijkstraImageGeodesicPath *	New ()
Protected Member Functions
	vtkDijkstraImageGeodesicPath ()
	~vtkDijkstraImageGeodesicPath ()
virtual int	FillInputPortInformation (int port, vtkInformation *info)
virtual int	RequestData (vtkInformation , vtkInformationVector , vtkInformationVector )
virtual void	BuildAdjacency (vtkDataSet *inData)
void	UpdateStaticCosts (vtkImageData *image)
virtual double	CalculateStaticEdgeCost (vtkDataSet *inData, vtkIdType u, vtkIdType v)
virtual double	CalculateDynamicEdgeCost (vtkDataSet *inData, vtkIdType u, vtkIdType v)
Protected Attributes
double	PixelSize
double	ImageWeight
double	EdgeLengthWeight
double	CurvatureWeight
bool	RebuildStaticCosts

Member Typedef Documentation

typedef vtkDijkstraGraphGeodesicPath vtkDijkstraImageGeodesicPath::Superclass

Standard methids for printing and determining type information.

Reimplemented from vtkDijkstraGraphGeodesicPath.

Definition at line 69 of file vtkDijkstraImageGeodesicPath.h.

Constructor & Destructor Documentation

vtkDijkstraImageGeodesicPath::vtkDijkstraImageGeodesicPath ( ) [protected]

vtkDijkstraImageGeodesicPath::~vtkDijkstraImageGeodesicPath ( ) [protected]

Member Function Documentation

static vtkDijkstraImageGeodesicPath* vtkDijkstraImageGeodesicPath::New ( ) [static]

Instantiate the class

Reimplemented from vtkDijkstraGraphGeodesicPath.

virtual const char* vtkDijkstraImageGeodesicPath::GetClassName ( ) [virtual]

Standard methids for printing and determining type information.

Reimplemented from vtkDijkstraGraphGeodesicPath.

static int vtkDijkstraImageGeodesicPath::IsTypeOf ( const char * type ) [static]

Standard methids for printing and determining type information.

Reimplemented from vtkDijkstraGraphGeodesicPath.

virtual int vtkDijkstraImageGeodesicPath::IsA ( const char * type ) [virtual]

Standard methids for printing and determining type information.

Reimplemented from vtkDijkstraGraphGeodesicPath.

static vtkDijkstraImageGeodesicPath* vtkDijkstraImageGeodesicPath::SafeDownCast ( vtkObject * o ) [static]

Standard methids for printing and determining type information.

Reimplemented from vtkDijkstraGraphGeodesicPath.

void vtkDijkstraImageGeodesicPath::PrintSelf	(	ostream &	os,
		vtkIndent	indent
	)			`[virtual]`

Standard methids for printing and determining type information.

Reimplemented from vtkDijkstraGraphGeodesicPath.

void vtkDijkstraImageGeodesicPath::SetInput ( vtkDataObject * )

Specify the image object which is used as a cost function.

Reimplemented from vtkPolyDataAlgorithm.

vtkImageData* vtkDijkstraImageGeodesicPath::GetInputAsImageData ( )

Specify the image object which is used as a cost function.

void vtkDijkstraImageGeodesicPath::SetImageWeight ( double )

Image cost weight.

virtual double vtkDijkstraImageGeodesicPath::GetImageWeight ( ) [virtual]

Image cost weight.

void vtkDijkstraImageGeodesicPath::SetEdgeLengthWeight ( double )

Edge length cost weight.

virtual double vtkDijkstraImageGeodesicPath::GetEdgeLengthWeight ( ) [virtual]

Edge length cost weight.

virtual void vtkDijkstraImageGeodesicPath::SetCurvatureWeight ( double ) [virtual]

Curvature cost weight.

virtual double vtkDijkstraImageGeodesicPath::GetCurvatureWeight ( ) [virtual]

Curvature cost weight.

virtual int vtkDijkstraImageGeodesicPath::FillInputPortInformation	(	int	port,
		vtkInformation *	info
	)			`[protected, virtual]`

Fill the input port information objects for this algorithm. This is invoked by the first call to GetInputPortInformation for each port so subclasses can specify what they can handle.

Reimplemented from vtkGeodesicPath.

virtual int vtkDijkstraImageGeodesicPath::RequestData	(	vtkInformation *	request,
		vtkInformationVector **	inputVector,
		vtkInformationVector *	outputVector
	)			`[protected, virtual]`