vtkPCAAnalysisFilter Class Reference

Performs principal component analysis of a set of aligned pointsets. More...

#include <vtkPCAAnalysisFilter.h>

Inheritance diagram for vtkPCAAnalysisFilter:

Collaboration diagram for vtkPCAAnalysisFilter:

List of all members.

Public Types
typedef vtkMultiBlockDataSetAlgorithm	Superclass
Public Member Functions
virtual int	IsA (const char *type)
vtkPCAAnalysisFilter *	NewInstance () const
void	PrintSelf (ostream &os, vtkIndent indent)
void	GetParameterisedShape (vtkFloatArray *b, vtkPointSet *shape)
void	GetShapeParameters (vtkPointSet *shape, vtkFloatArray *b, int bsize)
int	GetModesRequiredFor (double proportion)
virtual vtkFloatArray *	GetEvals ()
Static Public Member Functions
static int	IsTypeOf (const char *type)
static vtkPCAAnalysisFilter *	SafeDownCast (vtkObjectBase *o)
static vtkPCAAnalysisFilter *	New ()
Protected Member Functions
virtual vtkObjectBase *	NewInstanceInternal () const
	vtkPCAAnalysisFilter ()
	~vtkPCAAnalysisFilter ()
virtual int	RequestData (vtkInformation *, vtkInformationVector **, vtkInformationVector *)

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Detailed Description

Performs principal component analysis of a set of aligned pointsets.

vtkPCAAnalysisFilter is a filter that takes as input a set of aligned pointsets (any object derived from vtkPointSet) and performs a principal component analysis of the coordinates. This can be used to visualise the major or minor modes of variation seen in a set of similar biological objects with corresponding landmarks. vtkPCAAnalysisFilter is designed to work with the output from the vtkProcrustesAnalysisFilter vtkPCAAnalysisFilter requires a vtkMultiBlock input consisting of vtkPointSets as first level children.

vtkPCAAnalysisFilter is an implementation of (for example):

T. Cootes et al. : Active Shape Models - their training and application. Computer Vision and Image Understanding, 61(1):38-59, 1995.

The material can also be found in Tim Cootes' ever-changing online report published at his website: http://www.isbe.man.ac.uk/~bim/

Warning:

All of the input pointsets must have the same number of points.

Thanks:

Rasmus Paulsen and Tim Hutton who developed and contributed this class

See also:

vtkProcrustesAlignmentFilter

Tests:

vtkPCAAnalysisFilter (Tests)

Definition at line 61 of file vtkPCAAnalysisFilter.h.

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Member Typedef Documentation

typedef vtkMultiBlockDataSetAlgorithm vtkPCAAnalysisFilter::Superclass

Reimplemented from vtkMultiBlockDataSetAlgorithm.

Definition at line 64 of file vtkPCAAnalysisFilter.h.

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Constructor & Destructor Documentation

vtkPCAAnalysisFilter::vtkPCAAnalysisFilter

(

)

[protected]

vtkPCAAnalysisFilter::~vtkPCAAnalysisFilter

(

)

[protected]

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Member Function Documentation

static int vtkPCAAnalysisFilter::IsTypeOf

(

const char *

name

)

[static]

Return 1 if this class type is the same type of (or a subclass of) the named class. Returns 0 otherwise. This method works in combination with vtkTypeMacro found in vtkSetGet.h.

Reimplemented from vtkMultiBlockDataSetAlgorithm.

virtual int vtkPCAAnalysisFilter::IsA

(

const char *

name

)

[virtual]

Return 1 if this class is the same type of (or a subclass of) the named class. Returns 0 otherwise. This method works in combination with vtkTypeMacro found in vtkSetGet.h.

Reimplemented from vtkMultiBlockDataSetAlgorithm.

static vtkPCAAnalysisFilter* vtkPCAAnalysisFilter::SafeDownCast

(

vtkObjectBase *

o

)

[static]

Reimplemented from vtkMultiBlockDataSetAlgorithm.

virtual vtkObjectBase* vtkPCAAnalysisFilter::NewInstanceInternal

(

)

const [protected, virtual]

Reimplemented from vtkMultiBlockDataSetAlgorithm.

vtkPCAAnalysisFilter* vtkPCAAnalysisFilter::NewInstance

(

)

const

Reimplemented from vtkMultiBlockDataSetAlgorithm.

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

Prints information about the state of the filter.

Reimplemented from vtkMultiBlockDataSetAlgorithm.

static vtkPCAAnalysisFilter* vtkPCAAnalysisFilter::New

(

)

[static]

Creates with similarity transform.

Reimplemented from vtkMultiBlockDataSetAlgorithm.

virtual vtkFloatArray* vtkPCAAnalysisFilter::GetEvals

(

)

[virtual]

Get the vector of eigenvalues sorted in descending order

void vtkPCAAnalysisFilter::GetParameterisedShape	(	vtkFloatArray *	b,
		vtkPointSet *	shape
	)

Fills the shape with: mean + b[0] * sqrt(eigenvalue[0]) * eigenvector[0] + b[1] * sqrt(eigenvalue[1]) * eigenvector[1] ... + b[sizeb-1] * sqrt(eigenvalue[bsize-1]) * eigenvector[bsize-1] here b are the parameters expressed in standard deviations bsize is the number of parameters in the b vector This function assumes that shape is already allocated with the right size, it just moves the points.

void vtkPCAAnalysisFilter::GetShapeParameters	(	vtkPointSet *	shape,
		vtkFloatArray *	b,
		int	bsize
	)

Return the bsize parameters b that best model the given shape (in standard deviations). That is that the given shape will be approximated by: shape ~ mean + b[0] * sqrt(eigenvalue[0]) * eigenvector[0] + b[1] * sqrt(eigenvalue[1]) * eigenvector[1] ... + b[bsize-1] * sqrt(eigenvalue[bsize-1]) * eigenvector[bsize-1]

int vtkPCAAnalysisFilter::GetModesRequiredFor

(

double

proportion

)

Retrieve how many modes are necessary to model the given proportion of the variation. proportion should be between 0 and 1

virtual int vtkPCAAnalysisFilter::RequestData	(	vtkInformation *	,
		vtkInformationVector **	,
		vtkInformationVector *
	)		[protected, virtual]

Usual data generation method.

Reimplemented from vtkMultiBlockDataSetAlgorithm.

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

• dox/Filters/Hybrid/vtkPCAAnalysisFilter.h