itk::ShapedNeighborhoodIterator< TImage, TBoundaryCondition > Class Template Reference

#include <itkShapedNeighborhoodIterator.h>

Detailed Description

template<typename TImage, typename TBoundaryCondition = ZeroFluxNeumannBoundaryCondition<TImage>>
class itk::ShapedNeighborhoodIterator< TImage, TBoundaryCondition >

A neighborhood iterator which can take on an arbitrary shape.

General Information

The ShapedNeighborhoodIterator is a refinement of NeighborhoodIterator which allows the user to specify which of the neighborhood elements are active and which will be ignored. This is useful for applications which only need to work with a subset of the neighborhood around a pixel such as morphological operations or cellular automata. This iterator can also be used, for example, to specify "cross-shaped" neighborhood where only elements along a spatial axes are significant.

Constructing a shaped neighborhood iterator

A shaped neighborhood iterator is constructed by constructing a list of active neighbor locations. The list is called the ActiveIndexList. The methods ActivateOffset, DeactivateOffset, and ClearActiveList are used to construct the ActiveIndexList. The argument to Activate/DeactivateOffset is an itk::Offset which represents the ND spatial offset from the center of the neighborhood. For example, to activate the center pixel in the neighborhood, you would do the following:

using ImageType = Image<float, 3>;
ShapedNeighborhoodIterator<ImageType> it(radius, image, region);
ShapedNeighborhoodIterator<ImageType>::OffsetType offset = {{0,0,0}};
it.ActivateOffset(offset);

where radius, image, and region are as described in NeighborhoodIterator.

Once a neighborhood location has been activated, iteration (operator++, operator--, operator+=, operator-=) will update the value at the active location. Note that values at inactive locations will NOT be valid if queried.

Accessing elements in a shaped neighborhood.

To access the value at an active neighborhood location, you can use the standard GetPixel, SetPixel methods. SetPixel is not defined for ConstShapedNeighborhoodIterator. The class will not complain if you attempt to access a value at a non-active location, but be aware that the result will be undefined. Error checking is not done in this case for the sake of efficiency.

A second way to access active shaped neighborhood values is through a ShapedNeighborhoodIterator::Iterator or ConstShapedNeighborhoodIterator::ConstIterator. The following example demonstrates the use of these iterators.

using ImageType = Image<float, 3>;
ShapedNeighborhoodIterator<ImageType> it(radius, image, region);
...
it.ActivateOffset(offset1);
it.ActivateOffset(offset2);
it.ActivateOffset(offset3);
// etc..
...
ShapedNeighborhoodIterator<ImageType>::Iterator i;
for (i = it.Begin(); ! i.IsAtEnd(); ++i)
{ i.Set(i.Get() + 1.0); }
// you may also use i != i.End(), but IsAtEnd() may be slightly faster.

You can also iterate backward through the neighborhood active list.

i = it.End();
--i;
while (i != it.Begin())
{
  i.Set(i.Get() + 1.0);
  --i;
}
 i.Set(i.Get() + 1.0);

The Get() Set() syntax was chosen versus defining operator* for these iterators because lvalue vs. rvalue context information is needed to determine whether bounds checking must take place.

See also

Neighborhood

MORE INFORMATION

For a complete description of the ITK Image Iterators and their API, please see the Iterators chapter in the ITK Software Guide. The ITK Software Guide is available in print and as a free .pdf download from https://www.itk.org.

See also

ImageConstIterator

ConditionalConstIterator

ConstNeighborhoodIterator

ConstShapedNeighborhoodIterator

ConstSliceIterator

CorrespondenceDataStructureIterator

FloodFilledFunctionConditionalConstIterator

FloodFilledImageFunctionConditionalConstIterator

FloodFilledImageFunctionConditionalIterator

FloodFilledSpatialFunctionConditionalConstIterator

FloodFilledSpatialFunctionConditionalIterator

ImageConstIterator

ImageConstIteratorWithIndex

ImageIterator

ImageIteratorWithIndex

ImageLinearConstIteratorWithIndex

ImageLinearIteratorWithIndex

ImageRandomConstIteratorWithIndex

ImageRandomIteratorWithIndex

ImageRegionConstIterator

ImageRegionConstIteratorWithIndex

ImageRegionExclusionConstIteratorWithIndex

ImageRegionExclusionIteratorWithIndex

ImageRegionIterator

ImageRegionIteratorWithIndex

ImageRegionReverseConstIterator

ImageRegionReverseIterator

ImageReverseConstIterator

ImageReverseIterator

ImageSliceConstIteratorWithIndex

ImageSliceIteratorWithIndex

NeighborhoodIterator

PathConstIterator

PathIterator

ShapedNeighborhoodIterator

SliceIterator

ImageConstIteratorWithIndex

ShapedImageNeighborhoodRange

ITK Sphinx Examples:

• All ITK Sphinx Examples

• Iterate Over A Region With A Shaped Neighborhood Iterator Manually

• Iterate Over A Region With A Shaped Neighborhood Iterator

Definition at line 150 of file itkShapedNeighborhoodIterator.h.

Inheritance diagram for itk::ShapedNeighborhoodIterator< TImage, TBoundaryCondition >:

Collaboration diagram for itk::ShapedNeighborhoodIterator< TImage, TBoundaryCondition >:

Classes
struct	Iterator

Public Types
using	ConstIterator = typename AllocatorType::const_iterator
using	InternalPixelType = typename TImage::InternalPixelType
using	OffsetType = Offset< VDimension >
using	OffsetValueType = typename OffsetType::OffsetValueType
using	PixelType = typename TImage::PixelType
using	RadiusType = itk::Size< VDimension >
using	Self = ShapedNeighborhoodIterator
using	SizeType = itk::Size< VDimension >
using	SizeValueType = typename SizeType::SizeValueType
using	Superclass = ConstShapedNeighborhoodIterator< TImage, TBoundaryCondition >
Public Types inherited from itk::ConstShapedNeighborhoodIterator< TImage, TBoundaryCondition >
using	BoundaryConditionType = TBoundaryCondition
using	ImageBoundaryConditionPointerType = ImageBoundaryCondition< ImageType > *
using	ImageType = TImage
using	IndexListConstIterator = typename IndexListType::const_iterator
using	IndexListIterator = typename IndexListType::iterator
using	IndexListType = std::list< NeighborIndexType >
using	IndexType = Index< Self::Dimension >
using	IndexValueType = typename IndexType::IndexValueType
using	InternalPixelType = typename TImage::InternalPixelType
using	NeighborhoodType = Neighborhood< PixelType, Self::Dimension >
using	NeighborIndexType = typename NeighborhoodType::NeighborIndexType
using	OffsetType = Offset< VDimension >
using	OffsetValueType = typename OffsetType::OffsetValueType
using	PixelType = typename TImage::PixelType
using	RadiusType = itk::Size< VDimension >
using	RegionType = typename TImage::RegionType
using	Self = ConstShapedNeighborhoodIterator
using	SizeType = itk::Size< VDimension >
using	SizeValueType = typename SizeType::SizeValueType
using	Superclass = NeighborhoodIterator< TImage, TBoundaryCondition >

Public Member Functions
Iterator	Begin ()
ConstIterator	Begin () const
Iterator	End ()
ConstIterator	End () const
	ShapedNeighborhoodIterator ()=default
	ShapedNeighborhoodIterator (const ShapedNeighborhoodIterator &o)=delete
	ShapedNeighborhoodIterator (const SizeType &radius, const ImageType *ptr, const RegionType &region)
	~ShapedNeighborhoodIterator () override=default
Self &	operator= (const Self &orig)
Iterator	Begin ()
Iterator	End ()
Public Member Functions inherited from itk::ConstShapedNeighborhoodIterator< TImage, TBoundaryCondition >
const IndexListType &	GetActiveIndexList () const
IndexListType::size_type	GetActiveIndexListSize () const
Self &	operator++ ()
Self &	operator+= (const OffsetType &)
Self &	operator-- ()
Self &	operator-= (const OffsetType &)
void	PrintSelf (std::ostream &, Indent) const override
ConstIterator	Begin () const
ConstIterator	End () const
	ConstShapedNeighborhoodIterator ()=default
	~ConstShapedNeighborhoodIterator () override=default
	ConstShapedNeighborhoodIterator (const SizeType &radius, const ImageType *ptr, const RegionType &region)
	ConstShapedNeighborhoodIterator (const ConstShapedNeighborhoodIterator &)=delete
Self &	operator= (const Self &orig)
const SizeType	GetRadius () const
SizeValueType	GetRadius (DimensionValueType n) const
virtual NeighborIndexType	GetNeighborhoodIndex (const OffsetType &) const
NeighborIndexType	GetCenterNeighborhoodIndex () const
OffsetType	GetOffset (NeighborIndexType i) const
bool	operator== (const Self &other) const
TPixel &	GetElement (NeighborIndexType i)
void	Print (std::ostream &os) const
ITK_ITERATOR_VIRTUAL void	ActivateOffset (const OffsetType &off) ITK_ITERATOR_FINAL
ITK_ITERATOR_VIRTUAL void	DeactivateOffset (const OffsetType &off) ITK_ITERATOR_FINAL
template<typename TOffsets >
void	ActivateOffsets (const TOffsets &offsets)
ITK_ITERATOR_VIRTUAL void	ClearActiveList () ITK_ITERATOR_FINAL
template<typename TNeighborPixel >
void	CreateActiveListFromNeighborhood (const Neighborhood< TNeighborPixel, Self::Dimension > &)
void	CreateActiveListFromNeighborhood (const NeighborhoodType &neighborhood)

Static Public Attributes
static constexpr unsigned int	Dimension = TImage::ImageDimension
Static Public Attributes inherited from itk::ConstShapedNeighborhoodIterator< TImage, TBoundaryCondition >
static constexpr unsigned int	Dimension = TImage::ImageDimension

Protected Types
using	NeighborIndexType = SizeValueType

Protected Attributes
friend	Superclass
Protected Attributes inherited from itk::ConstShapedNeighborhoodIterator< TImage, TBoundaryCondition >
IndexListType	m_ActiveIndexList {}
bool	m_CenterIsActive { false }

Additional Inherited Members
Protected Member Functions inherited from itk::ConstShapedNeighborhoodIterator< TImage, TBoundaryCondition >
ITK_ITERATOR_VIRTUAL void	ActivateIndex (NeighborIndexType) ITK_ITERATOR_FINAL
ITK_ITERATOR_VIRTUAL void	DeactivateIndex (NeighborIndexType) ITK_ITERATOR_FINAL

Member Typedef Documentation

ConstIterator

template<typename TImage, typename TBoundaryCondition = ZeroFluxNeumannBoundaryCondition<TImage>>

using itk::Neighborhood< TPixel, VDimension, TAllocator >::ConstIterator = typename AllocatorType::const_iterator

Definition at line 76 of file itkNeighborhood.h.

InternalPixelType

template<typename TImage, typename TBoundaryCondition = ZeroFluxNeumannBoundaryCondition<TImage>>

using itk::ShapedNeighborhoodIterator< TImage, TBoundaryCondition >::InternalPixelType = typename TImage::InternalPixelType

Extract image type information.

Definition at line 155 of file itkShapedNeighborhoodIterator.h.

NeighborIndexType

template<typename TImage, typename TBoundaryCondition = ZeroFluxNeumannBoundaryCondition<TImage>>

using itk::Neighborhood< TPixel, VDimension, TAllocator >::NeighborIndexType = SizeValueType

protected

Type used to refer to the elements of the pixel list that are part of the neighborhood.

Definition at line 96 of file itkNeighborhood.h.

OffsetType

template<typename TImage, typename TBoundaryCondition = ZeroFluxNeumannBoundaryCondition<TImage>>

using itk::Neighborhood< TPixel, VDimension, TAllocator >::OffsetType = Offset<VDimension>

Offset type used to reference neighbor locations

Definition at line 86 of file itkNeighborhood.h.

OffsetValueType

template<typename TImage, typename TBoundaryCondition = ZeroFluxNeumannBoundaryCondition<TImage>>

using itk::ShapedNeighborhoodIterator< TImage, TBoundaryCondition >::OffsetValueType = typename OffsetType::OffsetValueType

Definition at line 167 of file itkShapedNeighborhoodIterator.h.

PixelType

template<typename TImage, typename TBoundaryCondition = ZeroFluxNeumannBoundaryCondition<TImage>>

using itk::ShapedNeighborhoodIterator< TImage, TBoundaryCondition >::PixelType = typename TImage::PixelType

Definition at line 156 of file itkShapedNeighborhoodIterator.h.

RadiusType

template<typename TImage, typename TBoundaryCondition = ZeroFluxNeumannBoundaryCondition<TImage>>

using itk::Neighborhood< TPixel, VDimension, TAllocator >::RadiusType = itk::Size<VDimension>

Radius type alias support

Definition at line 83 of file itkNeighborhood.h.

Self

template<typename TImage, typename TBoundaryCondition = ZeroFluxNeumannBoundaryCondition<TImage>>

using itk::ShapedNeighborhoodIterator< TImage, TBoundaryCondition >::Self = ShapedNeighborhoodIterator

Standard class type aliases.

Definition at line 162 of file itkShapedNeighborhoodIterator.h.

SizeType

template<typename TImage, typename TBoundaryCondition = ZeroFluxNeumannBoundaryCondition<TImage>>

using itk::Neighborhood< TPixel, VDimension, TAllocator >::SizeType = itk::Size<VDimension>

Size and value type alias support

Definition at line 79 of file itkNeighborhood.h.

SizeValueType

template<typename TImage, typename TBoundaryCondition = ZeroFluxNeumannBoundaryCondition<TImage>>

using itk::Neighborhood< TPixel, VDimension, TAllocator >::SizeValueType = typename SizeType::SizeValueType

Definition at line 80 of file itkNeighborhood.h.

Superclass

template<typename TImage, typename TBoundaryCondition = ZeroFluxNeumannBoundaryCondition<TImage>>

using itk::ShapedNeighborhoodIterator< TImage, TBoundaryCondition >::Superclass = ConstShapedNeighborhoodIterator<TImage, TBoundaryCondition>

Definition at line 163 of file itkShapedNeighborhoodIterator.h.

Constructor & Destructor Documentation

ShapedNeighborhoodIterator() [1/3]

template<typename TImage, typename TBoundaryCondition = ZeroFluxNeumannBoundaryCondition<TImage>>

itk::ShapedNeighborhoodIterator< TImage, TBoundaryCondition >::ShapedNeighborhoodIterator ( )

default

Default constructor

~ShapedNeighborhoodIterator()

template<typename TImage, typename TBoundaryCondition = ZeroFluxNeumannBoundaryCondition<TImage>>

itk::ShapedNeighborhoodIterator< TImage, TBoundaryCondition >::~ShapedNeighborhoodIterator ( )

overridedefault

Virtual destructor

ShapedNeighborhoodIterator() [2/3]

template<typename TImage, typename TBoundaryCondition = ZeroFluxNeumannBoundaryCondition<TImage>>

itk::ShapedNeighborhoodIterator< TImage, TBoundaryCondition >::ShapedNeighborhoodIterator ( const ShapedNeighborhoodIterator< TImage, TBoundaryCondition > &  o )

delete

Copy constructor

ShapedNeighborhoodIterator() [3/3]

template<typename TImage, typename TBoundaryCondition = ZeroFluxNeumannBoundaryCondition<TImage>>

itk::ShapedNeighborhoodIterator< TImage, TBoundaryCondition >::ShapedNeighborhoodIterator ( const SizeType &  radius, const ImageType *  ptr, const RegionType &  region  )

inline

Constructor which establishes the region size, neighborhood, and image over which to walk.

Definition at line 223 of file itkShapedNeighborhoodIterator.h.

Member Function Documentation

Begin() [1/3]

template<typename TImage, typename TBoundaryCondition = ZeroFluxNeumannBoundaryCondition<TImage>>

Iterator itk::ShapedNeighborhoodIterator< TImage, TBoundaryCondition >::Begin ( )

inline

Returns a const iterator for the neighborhood which points to the first pixel in the neighborhood.

Definition at line 245 of file itkShapedNeighborhoodIterator.h.

Begin() [2/3]

template<typename TImage, typename TBoundaryCondition = ZeroFluxNeumannBoundaryCondition<TImage>>

Iterator itk::Neighborhood< TPixel, VDimension, TAllocator >::Begin

inline

Definition at line 173 of file itkNeighborhood.h.

Begin() [3/3]

template<typename TImage, typename TBoundaryCondition = ZeroFluxNeumannBoundaryCondition<TImage>>

ConstIterator itk::Neighborhood< TPixel, VDimension, TAllocator >::Begin

inline

Definition at line 183 of file itkNeighborhood.h.

End() [1/3]

template<typename TImage, typename TBoundaryCondition = ZeroFluxNeumannBoundaryCondition<TImage>>

Iterator itk::ShapedNeighborhoodIterator< TImage, TBoundaryCondition >::End ( )

inline

Returns a const iterator for the neighborhood which points to the first pixel in the neighborhood.

Definition at line 250 of file itkShapedNeighborhoodIterator.h.

End() [2/3]

template<typename TImage, typename TBoundaryCondition = ZeroFluxNeumannBoundaryCondition<TImage>>

Iterator itk::Neighborhood< TPixel, VDimension, TAllocator >::End

inline

STL-style iterator support.

Definition at line 168 of file itkNeighborhood.h.

End() [3/3]

template<typename TImage, typename TBoundaryCondition = ZeroFluxNeumannBoundaryCondition<TImage>>

ConstIterator itk::Neighborhood< TPixel, VDimension, TAllocator >::End

inline

Definition at line 178 of file itkNeighborhood.h.

operator=()

template<typename TImage, typename TBoundaryCondition = ZeroFluxNeumannBoundaryCondition<TImage>>

Self& itk::ShapedNeighborhoodIterator< TImage, TBoundaryCondition >::operator= ( const Self &  orig )

inline

Assignment operator

Definition at line 235 of file itkShapedNeighborhoodIterator.h.

Member Data Documentation

Dimension

template<typename TImage, typename TBoundaryCondition = ZeroFluxNeumannBoundaryCondition<TImage>>

constexpr unsigned int itk::ShapedNeighborhoodIterator< TImage, TBoundaryCondition >::Dimension = TImage::ImageDimension

staticconstexpr

Save the image dimension.

Definition at line 159 of file itkShapedNeighborhoodIterator.h.

Superclass

template<typename TImage, typename TBoundaryCondition = ZeroFluxNeumannBoundaryCondition<TImage>>

friend itk::ShapedNeighborhoodIterator< TImage, TBoundaryCondition >::Superclass

protected

Definition at line 260 of file itkShapedNeighborhoodIterator.h.

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

• itkShapedNeighborhoodIterator.h