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

itk::AntiAliasBinaryImageFilter< TInputImage, TOutputImage > Class Template Reference

#include <itkAntiAliasBinaryImageFilter.h>

Inheritance diagram for itk::AntiAliasBinaryImageFilter< TInputImage, TOutputImage >:

Inheritance graph
[legend]
Collaboration diagram for itk::AntiAliasBinaryImageFilter< TInputImage, TOutputImage >:

Collaboration graph
[legend]
List of all members.

Public Types

typedef AntiAliasBinaryImageFilter Self
typedef SparseFieldLevelSetImageFilter<
TInputImage, TOutputImage > 		Superclass
typedef SmartPointer< Self > Pointer
typedef SmartPointer< const
Self > 		ConstPointer
typedef Superclass::ValueType ValueType
typedef Superclass::IndexType IndexType
typedef Superclass::TimeStepType TimeStepType
typedef Superclass::OutputImageType OutputImageType
typedef Superclass::InputImageType InputImageType
typedef CurvatureFlowFunction<
OutputImageType > 		CurvatureFunctionType
typedef TInputImage::ValueType BinaryValueType

Public Member Functions

virtual const char * GetClassName () const
virtual void SetMaximumRMSError (ValueType _arg)
virtual ValueType GetMaximumRMSError ()
virtual void SetMaximumIterations (unsigned int _arg)
virtual unsigned int GetMaximumIterations ()
virtual BinaryValueType GetUpperBinaryValue ()
virtual BinaryValueType GetLowerBinaryValue ()

Static Public Member Functions

Pointer New ()

Protected Member Functions

 AntiAliasBinaryImageFilter ()
 ~AntiAliasBinaryImageFilter ()
virtual void PrintSelf (std::ostream &os, Indent indent) const
virtual ValueType CalculateUpdateValue (const IndexType &idx, const TimeStepType &dt, const ValueType &value, const ValueType &change)
bool Halt ()
void GenerateData ()

Detailed Description

template<class TInputImage, class TOutputImage>
class itk::AntiAliasBinaryImageFilter< TInputImage, TOutputImage >

This filter implements a surface-fitting method for estimation of a surface from a binary volume. This process can be used to reduce aliasing artifacts which result in visualization of binary partitioned surfaces.
The binary volume (filter input) is used as a set of constraints in an iterative relaxation process of an estimated ND surface. The surface is described implicitly as the zero level set of a volume $ \phi $ and allowed to deform under curvature flow. A set of contraints is imposed on this movement as follows:

\[ u_{i,j,k}^{n+1} = \left\{ \begin{array}{ll} \mbox{max} (u_{i,j,k}^{n} + \Delta t H_{i,j,k}^{n}, 0) & \mbox{$B_{i,j,k} = 1$} \\ \mbox{min} (u_{i,j,k}^{n} + \Delta t H_{i,j,k}^{n}, 0) & \mbox{$B_{i,j,k} = -1$} \end{array}\right. \]

where $ u_{i,j,k}^{n} $ is the value of $ \phi $ at discrete index $ (i,j,k) $ and iteration $ n $, $ H $ is the gradient magnitude times mean curvature of $ \phi $, and $ B $ is the binary input volume, with 1 denoting an inside pixel and -1 denoting an outside pixel.
NOTES
This implementation uses a sparse field level set solver instead of the narrow band implementation described in the reference below, which may introduce some differences in how fast and how accurately (in terms of RMS error) the solution converges.
REFERENCES
Whitaker, Ross. "Reducing Aliasing Artifacts In Iso-Surfaces of Binary Volumes" IEEE Volume Visualization and Graphics Symposium, October 2000, pp.23-32.
PARAMETERS
The MaximumRMSChange parameter is used to determine when the solution has converged. A lower value will result in a tighter-fitting solution, but will require more computations. Too low a value could put the solver into an infinite loop. Values should always be less than 1.0. A value of 0.07 is a good starting estimate.
The MaximumIterations parameter can be used to halt the solution after a specified number of iterations.
INPUT
The input is an N-dimensional image of any type. It is assumed to be a binary image. The filter will use an isosurface value that is halfway between the min and max values in the image. A signed data type is *not* necessary for the input.
OUTPUT
The filter will output a level set image of real, signed values. The zero crossings of this (N-dimensional) image represent the position of the isosurface value of interest. Values outside the zero level set are negative and values inside the zero level set are positive values.
IMPORTANT!
The output image type you use to instantiate this filter should be a real valued scalar type. In other words: doubles or floats.
USING THIS FILTER
The filter is relatively straightforward to use. Tests and examples exist to illustrate. The important thing is to understand the input and output types so you can properly interperet your results.
In the common case, the only parameter that will need to be set is the MaximumRMSChange parameter, which determines when the solver halts.

Definition at line 100 of file itkAntiAliasBinaryImageFilter.h.

Member Typedef Documentation

template<class TInputImage, class TOutputImage>
typedef TInputImage::ValueType itk::AntiAliasBinaryImageFilter< TInputImage, TOutputImage >::BinaryValueType
 

ValueType of the input binary image Definition at line 123 of file itkAntiAliasBinaryImageFilter.h.

template<class TInputImage, class TOutputImage>
typedef SmartPointer<const Self> itk::AntiAliasBinaryImageFilter< TInputImage, TOutputImage >::ConstPointer
 

Reimplemented from itk::SparseFieldLevelSetImageFilter< TInputImage, TOutputImage >.

Definition at line 109 of file itkAntiAliasBinaryImageFilter.h.

template<class TInputImage, class TOutputImage>
typedef CurvatureFlowFunction<OutputImageType> itk::AntiAliasBinaryImageFilter< TInputImage, TOutputImage >::CurvatureFunctionType
 

The function type which will calculate the curvature flow Definition at line 120 of file itkAntiAliasBinaryImageFilter.h.

template<class TInputImage, class TOutputImage>
typedef Superclass::IndexType itk::AntiAliasBinaryImageFilter< TInputImage, TOutputImage >::IndexType
 

Reimplemented from itk::SparseFieldLevelSetImageFilter< TInputImage, TOutputImage >.

Definition at line 113 of file itkAntiAliasBinaryImageFilter.h.

template<class TInputImage, class TOutputImage>
typedef Superclass::InputImageType itk::AntiAliasBinaryImageFilter< TInputImage, TOutputImage >::InputImageType
 

Information derived from the image types.

Reimplemented from itk::SparseFieldLevelSetImageFilter< TInputImage, TOutputImage >.

Definition at line 116 of file itkAntiAliasBinaryImageFilter.h.

template<class TInputImage, class TOutputImage>
typedef Superclass::OutputImageType itk::AntiAliasBinaryImageFilter< TInputImage, TOutputImage >::OutputImageType
 

Some convenient typedefs.

Reimplemented from itk::SparseFieldLevelSetImageFilter< TInputImage, TOutputImage >.

Definition at line 115 of file itkAntiAliasBinaryImageFilter.h.

template<class TInputImage, class TOutputImage>
typedef SmartPointer<Self> itk::AntiAliasBinaryImageFilter< TInputImage, TOutputImage >::Pointer
 

Reimplemented from itk::SparseFieldLevelSetImageFilter< TInputImage, TOutputImage >.

Definition at line 108 of file itkAntiAliasBinaryImageFilter.h.

template<class TInputImage, class TOutputImage>
typedef AntiAliasBinaryImageFilter itk::AntiAliasBinaryImageFilter< TInputImage, TOutputImage >::Self
 

Standard class typedefs

Reimplemented from itk::SparseFieldLevelSetImageFilter< TInputImage, TOutputImage >.

Definition at line 106 of file itkAntiAliasBinaryImageFilter.h.

template<class TInputImage, class TOutputImage>
typedef SparseFieldLevelSetImageFilter<TInputImage, TOutputImage> itk::AntiAliasBinaryImageFilter< TInputImage, TOutputImage >::Superclass
 

Reimplemented from itk::SparseFieldLevelSetImageFilter< TInputImage, TOutputImage >.

Definition at line 107 of file itkAntiAliasBinaryImageFilter.h.

template<class TInputImage, class TOutputImage>
typedef Superclass::TimeStepType itk::AntiAliasBinaryImageFilter< TInputImage, TOutputImage >::TimeStepType
 

Typedefs from the superclass

Reimplemented from itk::SparseFieldLevelSetImageFilter< TInputImage, TOutputImage >.

Definition at line 114 of file itkAntiAliasBinaryImageFilter.h.

template<class TInputImage, class TOutputImage>
typedef Superclass::ValueType itk::AntiAliasBinaryImageFilter< TInputImage, TOutputImage >::ValueType
 

Inherited typedef from the superclass.

Reimplemented from itk::SparseFieldLevelSetImageFilter< TInputImage, TOutputImage >.

Definition at line 112 of file itkAntiAliasBinaryImageFilter.h.

Constructor & Destructor Documentation

template<class TInputImage, class TOutputImage>
itk::AntiAliasBinaryImageFilter< TInputImage, TOutputImage >::AntiAliasBinaryImageFilter (   )  [protected]
 

template<class TInputImage, class TOutputImage>
itk::AntiAliasBinaryImageFilter< TInputImage, TOutputImage >::~AntiAliasBinaryImageFilter (   )  [inline, protected]
 

Definition at line 152 of file itkAntiAliasBinaryImageFilter.h.

Member Function Documentation

template<class TInputImage, class TOutputImage>
virtual ValueType itk::AntiAliasBinaryImageFilter< TInputImage, TOutputImage >::CalculateUpdateValue (  const IndexType &  idx,
const TimeStepType &  dt,
const ValueType &  value,
const ValueType &  change
)  [inline, protected, virtual]
 

Overridden from the parent class to indroduce a constraint on surface flow under certain conditions.

Reimplemented from itk::SparseFieldLevelSetImageFilter< TInputImage, TOutputImage >.

template<class TInputImage, class TOutputImage>
void itk::AntiAliasBinaryImageFilter< TInputImage, TOutputImage >::GenerateData (   )  [protected, virtual]
 

Overridden from ProcessObject to set certain values before starting the finite difference solver and then create an appropriate output

Reimplemented from itk::FiniteDifferenceImageFilter< TInputImage, TOutputImage >.

template<class TInputImage, class TOutputImage>
virtual const char* itk::AntiAliasBinaryImageFilter< TInputImage, TOutputImage >::GetClassName (   )  const [virtual]
 

Run-time type information (and related methods).

Reimplemented from itk::SparseFieldLevelSetImageFilter< TInputImage, TOutputImage >.

template<class TInputImage, class TOutputImage>
virtual BinaryValueType itk::AntiAliasBinaryImageFilter< TInputImage, TOutputImage >::GetLowerBinaryValue (   )  [virtual]
 

Get the upper and lower binary values in the input image.

template<class TInputImage, class TOutputImage>
virtual unsigned int itk::AntiAliasBinaryImageFilter< TInputImage, TOutputImage >::GetMaximumIterations (   )  [virtual]
 

Set/Get the maximum number of iterations allowed for the solver. This prevents infinite loops when a solution "bounces". The filter halt and issue a warning when this number is reached because the MaximumRMSError criteria will not have been met.

template<class TInputImage, class TOutputImage>
virtual ValueType itk::AntiAliasBinaryImageFilter< TInputImage, TOutputImage >::GetMaximumRMSError (   )  [virtual]
 

Set/Get the maximum RMS error allowed for the solution. The solver will halt once this threshold has been reached.

template<class TInputImage, class TOutputImage>
virtual BinaryValueType itk::AntiAliasBinaryImageFilter< TInputImage, TOutputImage >::GetUpperBinaryValue (   )  [virtual]
 

Get the upper and lower binary values in the input image.

template<class TInputImage, class TOutputImage>
bool itk::AntiAliasBinaryImageFilter< TInputImage, TOutputImage >::Halt (   )  [inline, protected, virtual]
 

Overrides the default Halt() method to stop only when the RMS error is less than a user-specified threshold.

Implements itk::FiniteDifferenceImageFilter< TInputImage, TOutputImage >.

Definition at line 164 of file itkAntiAliasBinaryImageFilter.h.

References itkWarningMacro.

template<class TInputImage, class TOutputImage>
Pointer itk::AntiAliasBinaryImageFilter< TInputImage, TOutputImage >::New (   )  [static]
 

Method for creation through the object factory.

Reimplemented from itk::SparseFieldLevelSetImageFilter< TInputImage, TOutputImage >.

template<class TInputImage, class TOutputImage>
virtual void itk::AntiAliasBinaryImageFilter< TInputImage, TOutputImage >::PrintSelf (  std::ostream &  os,
Indent  indent
)  const [protected, virtual]
 

Methods invoked by Print() to print information about the object including superclasses. Typically not called by the user (use Print() instead) but used in the hierarchical print process to combine the output of several classes.

Reimplemented from itk::SparseFieldLevelSetImageFilter< TInputImage, TOutputImage >.

template<class TInputImage, class TOutputImage>
virtual void itk::AntiAliasBinaryImageFilter< TInputImage, TOutputImage >::SetMaximumIterations (  unsigned int  _arg  )  [virtual]
 

Set/Get the maximum number of iterations allowed for the solver. This prevents infinite loops when a solution "bounces". The filter halt and issue a warning when this number is reached because the MaximumRMSError criteria will not have been met.

template<class TInputImage, class TOutputImage>
virtual void itk::AntiAliasBinaryImageFilter< TInputImage, TOutputImage >::SetMaximumRMSError (  ValueType  _arg  )  [virtual]
 

Set/Get the maximum RMS error allowed for the solution. The solver will halt once this threshold has been reached.

The documentation for this class was generated from the following file:
Generated at Sat Mar 31 02:36:06 2007 for ITK by doxygen 1.3.8 written by Dimitri van Heesch, © 1997-2000