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vtkPCAAnalysisFilter Class Reference

#include <vtkPCAAnalysisFilter.h>

Inheritance diagram for vtkPCAAnalysisFilter:

[legend]Collaboration diagram for vtkPCAAnalysisFilter:

[legend]List of all members.

Detailed Description

Performs principal component analysis of a set of aligned pointsets.

Date:: 2002/02/13 10:08:35

Revision:: 1.2

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

Call SetNumberOfInputs(n) before calling SetInput(0) ... SetInput(n-1). Retrieve the outputs using GetOutput(0) ... GetOutput(n-1).

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

Created by:

Paulsen, Rasmus Reinhold

CVS contributions (if > 5%):

Paulsen, Rasmus Reinhold (88%)
Hutton, Tim (9%)

CVS logs (CVSweb):

.h (/Hybrid/vtkPCAAnalysisFilter.h)
.cxx (/Hybrid/vtkPCAAnalysisFilter.cxx)

Tests:: vtkPCAAnalysisFilter (Tests)

Definition at line 76 of file vtkPCAAnalysisFilter.h.

Public Types

typedef vtkSource Superclass

Public Methods

virtual const char * GetClassName ()

virtual int IsA (const char *type)

void PrintSelf (ostream &os, vtkIndent indent)

void SetNumberOfInputs (int n)

void SetInput (int idx, vtkPointSet *p)

vtkPointSet * GetOutput (int idx)

void GetParameterisedShape (vtkFloatArray *b, vtkPointSet *shape)

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

vtkPointSet * GetInput (int idx)

int GetModesRequiredFor (float proportion)

virtual vtkFloatArray * GetEvals ()

Static Public Methods

int IsTypeOf (const char *type)

vtkPCAAnalysisFilter * SafeDownCast (vtkObject *o)

vtkPCAAnalysisFilter * New ()

Protected Methods

vtkPCAAnalysisFilter ()

~vtkPCAAnalysisFilter ()

void Execute ()

Member Typedef Documentation

typedef vtkSource vtkPCAAnalysisFilter::Superclass

Reimplemented from vtkSource.
Definition at line 79 of file vtkPCAAnalysisFilter.h.

Constructor & Destructor Documentation

vtkPCAAnalysisFilter::vtkPCAAnalysisFilter ( ) [protected]

vtkPCAAnalysisFilter::~vtkPCAAnalysisFilter ( ) [protected]

Member Function Documentation

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

Reimplemented from vtkSource.

int vtkPCAAnalysisFilter::IsTypeOf ( const char * type ) [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 vtkTypeRevisionMacro found in vtkSetGet.h.
Reimplemented from vtkSource.

virtual int vtkPCAAnalysisFilter::IsA ( const char * type ) [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 vtkTypeRevisionMacro found in vtkSetGet.h.
Reimplemented from vtkSource.

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

Reimplemented from vtkSource.

void vtkPCAAnalysisFilter::PrintSelf ( ostream & os,

vtkIndent indent

) [virtual]

Prints information about the state of the filter.
Reimplemented from vtkSource.

vtkPCAAnalysisFilter* vtkPCAAnalysisFilter::New ( ) [static]

Creates with similarity transform.
Reimplemented from vtkObject.

virtual vtkFloatArray* vtkPCAAnalysisFilter::GetEvals ( ) [virtual]

Get the vector of eigenvalues sorted in descending order

void vtkPCAAnalysisFilter::SetNumberOfInputs ( int n )

Specify how many pointsets are going to be given as input.
Reimplemented from vtkProcessObject.

void vtkPCAAnalysisFilter::SetInput ( int idx,

vtkPointSet * p

)

Specify the input pointset with index idx. Call SetNumberOfInputs before calling this function.

vtkPointSet* vtkPCAAnalysisFilter::GetOutput ( int idx )

Retrieve the output point set with index idx. The output is the eigenvector sorted according to their eigenvalues (descending order)
Reimplemented from vtkSource.

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 allready 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]

vtkPointSet* vtkPCAAnalysisFilter::GetInput ( int idx )

Retrieve the input with index idx (usually only used for pipeline tracing).

int vtkPCAAnalysisFilter::GetModesRequiredFor ( float proportion )

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

void vtkPCAAnalysisFilter::Execute ( ) [protected, virtual]

Usual data generation method.
Reimplemented from vtkSource.

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

Hybrid/vtkPCAAnalysisFilter.h


Public Types
typedef vtkSource	Superclass
Public Methods
virtual const char *	GetClassName ()
virtual int	IsA (const char *type)
void	PrintSelf (ostream &os, vtkIndent indent)
void	SetNumberOfInputs (int n)
void	SetInput (int idx, vtkPointSet *p)
vtkPointSet *	GetOutput (int idx)
void	GetParameterisedShape (vtkFloatArray b, vtkPointSet shape)
void	GetShapeParameters (vtkPointSet shape, vtkFloatArray b, int bsize)
vtkPointSet *	GetInput (int idx)
int	GetModesRequiredFor (float proportion)

virtual vtkFloatArray *	GetEvals ()
Static Public Methods
int	IsTypeOf (const char *type)
vtkPCAAnalysisFilter *	SafeDownCast (vtkObject *o)
vtkPCAAnalysisFilter *	New ()
Protected Methods
	vtkPCAAnalysisFilter ()
	~vtkPCAAnalysisFilter ()
void	Execute ()