Main Page   Groups   Namespace List   Class Hierarchy   Alphabetical List   Compound List   File List   Namespace Members   Compound Members   File Members   Concepts

itk::ImageMomentsCalculator< TImage > Class Template Reference
[Operators]

Compute moments of an n-dimensional image. More...

#include <itkImageMomentsCalculator.h>

Collaboration diagram for itk::ImageMomentsCalculator< TImage >:

Collaboration graph
[legend]
List of all members.

Public Types

typedef ImageMomentsCalculator<
TImage > 
Self
typedef double ScalarType
typedef Vector< ScalarType,
itkGetStaticConstMacro(ImageDimension) 
VectorType )
typedef Matrix< ScalarType,
itkGetStaticConstMacro(ImageDimension),
itkGetStaticConstMacro(ImageDimension) 
MatrixType )
typedef TImage ImageType
typedef ImageType::Pointer ImagePointer
typedef AffineTransform< double,
itkGetStaticConstMacro(ImageDimension) 
AffineTransformType )
typedef AffineTransformType::Pointer AffineTransformPointer

Public Methods

 itkStaticConstMacro (ImageDimension, unsigned int, TImage::ImageDimension)
void ComputeMoments (const ImageType *image)
ScalarType GetTotalMass ()
VectorType GetFirstMoments ()
MatrixType GetSecondMoments ()
VectorType GetCenterOfGravity ()
MatrixType GetCentralMoments ()
VectorType GetPrincipalMoments ()
AffineTransformPointer GetPrincipalAxesToPhysicalAxesTransform (void) const
AffineTransformPointer GetPhysicalAxesToPrincipalAxesTransform (void) const
 ImageMomentsCalculator ()
 ImageMomentsCalculator (const ImageType *image)
 ~ImageMomentsCalculator ()
MatrixType GetPrincipalAxes ()

Detailed Description

template<class TImage>
class itk::ImageMomentsCalculator< TImage >

Compute moments of an n-dimensional image.

This class provides methods for computing the moments and related properties of a single-echo image. Computing the (non-central) moments of a large image can easily take a million times longer than computing the various other values derived from them, so we compute the moments only on explicit request, and save their values (in an ImageMomentsCalculator object) for later retrieval by the user.

The non-central moments computed by this class are not really intended for general use and are therefore in index coordinates; that is, we pretend that the index that selects a particular pixel also equals its physical coordinates. The center of gravity, central moments, principal moments and principal axes are all more generally useful and are computed in the physical coordinates defined by the Origin and Spacing parameters of the image.

The methods that return values return the values themselves rather than references because the cost is small compared to the cost of computing the moments and doing so simplifies memory management for the caller.

Todo:
It's not yet clear how multi-echo images should be handled here.

Definition at line 59 of file itkImageMomentsCalculator.h.


Member Typedef Documentation

template<class TImage>
typedef AffineTransformType::Pointer itk::ImageMomentsCalculator< TImage >::AffineTransformPointer
 

Definition at line 88 of file itkImageMomentsCalculator.h.

template<class TImage>
typedef AffineTransform<double,itkGetStaticConstMacro(ImageDimension) itk::ImageMomentsCalculator< TImage >::AffineTransformType)
 

Affine transform for mapping to and from principal axis

Definition at line 87 of file itkImageMomentsCalculator.h.

template<class TImage>
typedef ImageType::Pointer itk::ImageMomentsCalculator< TImage >::ImagePointer
 

Standard image type pointer within this class.

Definition at line 84 of file itkImageMomentsCalculator.h.

template<class TImage>
typedef TImage itk::ImageMomentsCalculator< TImage >::ImageType
 

Standard image type within this class.

Definition at line 81 of file itkImageMomentsCalculator.h.

template<class TImage>
typedef Matrix<ScalarType, itkGetStaticConstMacro(ImageDimension), itkGetStaticConstMacro(ImageDimension) itk::ImageMomentsCalculator< TImage >::MatrixType)
 

Standard matrix type within this class.

Definition at line 78 of file itkImageMomentsCalculator.h.

template<class TImage>
typedef double itk::ImageMomentsCalculator< TImage >::ScalarType
 

Standard scalar type within this class.

Definition at line 70 of file itkImageMomentsCalculator.h.

template<class TImage>
typedef ImageMomentsCalculator<TImage> itk::ImageMomentsCalculator< TImage >::Self
 

Standard class typedefs.

Definition at line 63 of file itkImageMomentsCalculator.h.

template<class TImage>
typedef Vector<ScalarType,itkGetStaticConstMacro(ImageDimension) itk::ImageMomentsCalculator< TImage >::VectorType)
 

Standard vector type within this class.

Definition at line 73 of file itkImageMomentsCalculator.h.


Constructor & Destructor Documentation

template<class TImage>
itk::ImageMomentsCalculator< TImage >::ImageMomentsCalculator  
 

Construct an ImageMomentsCalculator object. This method constructs a new ImageMomentsCalculator object that contains no stored moments information; this information can be added later by calling the ComputeMoments method.

template<class TImage>
itk::ImageMomentsCalculator< TImage >::ImageMomentsCalculator const ImageType   image
 

Compute moments of an image and save in an ImageMomentsCalculator object. This method constructs a new ImageMomentsCalculator object and stores in it the moments of the image given as argument. The values of these moments and related parameters can be retrieved by using * other methods of the object constructed.

template<class TImage>
itk::ImageMomentsCalculator< TImage >::~ImageMomentsCalculator  
 

Destroy an ImageMomentsCalculator object.


Member Function Documentation

template<class TImage>
void itk::ImageMomentsCalculator< TImage >::ComputeMoments const ImageType   image
 

Compute moments of a new or modified image. This method computes the moments of the image given as a parameter and stores them in the object. The values of these moments and related parameters can then be retrieved by using other methods of this object.

template<class TImage>
VectorType itk::ImageMomentsCalculator< TImage >::GetCenterOfGravity  
 

Return center of gravity, in physical coordinates. This method returns the center of gravity of the image whose moments were last computed by this object. The center of gravity is computed in physical coordinates.

template<class TImage>
MatrixType itk::ImageMomentsCalculator< TImage >::GetCentralMoments  
 

Return second central moments, in physical coordinates. This method returns the central second moments of the image whose moments were last computed by this object. The central moments are computed in physical coordinates.

template<class TImage>
VectorType itk::ImageMomentsCalculator< TImage >::GetFirstMoments  
 

Return first moments about origin, in index coordinates. This method returns the first moments around the origin of the image whose moments were last computed by this object. For simplicity, these moments are computed in index coordinates rather than physical coordinates.

template<class TImage>
AffineTransformPointer itk::ImageMomentsCalculator< TImage >::GetPhysicalAxesToPrincipalAxesTransform void    const
 

Get the affine transform from physical axes to principal axes This method returns an affine transform which transforms from the physical coordinate system to the principal axes coordinate system.

template<class TImage>
MatrixType itk::ImageMomentsCalculator< TImage >::GetPrincipalAxes  
 

Return principal axes, in physical coordinates. This method returns the principal axes of the image whose moments were last computed by this object. The moments are returned as an orthogonal matrix, each row of which corresponds to one principal moment; for example, the principal axis corresponding to the smallest principal moment is the vector m[0], where m is the value returned by this method. The matrix of principal axes is guaranteed to be a proper rotation; that is, to have determinant +1 and to preserve parity. (Unless you have foolishly made one or more of the spacing values negative; in that case, _you_ get to figure out the consequences.) The moments are computed in physical coordinates.

template<class TImage>
AffineTransformPointer itk::ImageMomentsCalculator< TImage >::GetPrincipalAxesToPhysicalAxesTransform void    const
 

Get the affine transform from principal axes to physical axes This method returns an affine transform which transforms from the principal axes coordinate system to physical coordinates.

template<class TImage>
VectorType itk::ImageMomentsCalculator< TImage >::GetPrincipalMoments  
 

Return principal moments, in physical coordinates. This method returns the principal moments of the image whose moments were last computed by this object. The moments are returned as a vector, with the principal moments ordered from smallest to largest. The moments are computed in physical coordinates.

template<class TImage>
MatrixType itk::ImageMomentsCalculator< TImage >::GetSecondMoments  
 

Return second moments about origin, in index coordinates. This method returns the second moments around the origin of the image whose moments were last computed by this object. For simplicity, these moments are computed in index coordinates rather than physical coordinates.

template<class TImage>
ScalarType itk::ImageMomentsCalculator< TImage >::GetTotalMass  
 

Return the total mass (or zeroth moment) of an image. This method returns the sum of pixel intensities (also known as the zeroth moment or the total mass) of the image whose moments were last computed by this object.

template<class TImage>
itk::ImageMomentsCalculator< TImage >::itkStaticConstMacro ImageDimension   ,
unsigned    int,
TImage::ImageDimension   
 

Extract the dimension of the image.


The documentation for this class was generated from the following file:
Generated at Fri May 21 01:46:16 2004 for ITK by doxygen 1.2.15 written by Dimitri van Heesch, © 1997-2000