ITK  5.0.0
Insight Segmentation and Registration Toolkit
Public Types | Public Member Functions | List of all members
itk::ImageRegionConstIteratorWithOnlyIndex< TImage > Class Template Reference

#include <itkImageRegionConstIteratorWithOnlyIndex.h>

+ Inheritance diagram for itk::ImageRegionConstIteratorWithOnlyIndex< TImage >:
+ Collaboration diagram for itk::ImageRegionConstIteratorWithOnlyIndex< TImage >:

Detailed Description

template<typename TImage>
class itk::ImageRegionConstIteratorWithOnlyIndex< TImage >

A multi-dimensional iterator templated over image type that walks an image region and is specialized to keep track of its index location and safely support images of type ImageBase.

The "WithOnlyIndex" family of iteators was designed for algorithms that use only the locations of image pixels in calculations. Unlike ImageRegionIterator, which calculates an index only when requested, ImageRegionIteratorWithOnlyIndex maintains its index location as a member variable that is updated during increment and decrement operations. Iteration speed is penalized, but index queries become more efficient.

ImageRegionConstIteratorWithOnlyIndex is a multi-dimensional iterator, requiring more information be specified before the iterator can be used than conventional iterators. Whereas the std::vector::iterator from the STL only needs to be passed a pointer to establish the iterator, the multi-dimensional image iterator needs a pointer, the size of the region, and the start index of the region. To gain access to this information, ImageRegionConstIteratorWithOnlyIndex holds a reference to the image over which it is traversing.

ImageRegionConstIteratorWithOnlyIndex assumes a particular layout of the image data. The is arranged in a 1D array as if it were [][][][slice][row][col] with Index[0] = col, Index[1] = row, Index[2] = slice, etc.

operator++ provides a simple syntax for walking around a region of a multidimensional image. operator++ iterates across a row, constraining the movement to within a region of image. When the iterator reaches the boundary of the region along a row, the iterator automatically wraps to the next row, starting at the first pixel in the row that is part of the region. This allows for simple processing loops of the form:

IteratorType it( image, image->GetRequestedRegion() );
it.Begin();
while( ! it.IsAtEnd() )
{
std::cout << it.GetIndex() << std::endl;
++it;
}

It also can be used for walking in the reverse direction like

IteratorType it( image, image->GetRequestedRegion() );
it.End();
while( !it.IsAtBegin() )
{
std::cout << it.GetIndex() << std::endl;
--it;
}
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.

Index-only iterators:

See Also
ImageRandomConstIteratorWithOnlyIndex
ConstNeighborhoodIteratorWithOnlyIndex

Pixel data-access iterators:

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

Definition at line 130 of file itkImageRegionConstIteratorWithOnlyIndex.h.

Public Types

using ImageType = typename Superclass::ImageType
 
using IndexType = typename Superclass::IndexType
 
using OffsetType = typename Superclass::OffsetType
 
using RegionType = typename Superclass::RegionType
 
using Self = ImageRegionConstIteratorWithOnlyIndex
 
using SizeType = typename Superclass::SizeType
 
using Superclass = ImageConstIteratorWithOnlyIndex< TImage >
 
- Public Types inherited from itk::ImageConstIteratorWithOnlyIndex< TImage >
using ImageType = TImage
 
using IndexType = typename TImage::IndexType
 
using IndexValueType = typename IndexType::IndexValueType
 
using OffsetType = typename TImage::OffsetType
 
using OffsetValueType = typename OffsetType::OffsetValueType
 
using RegionType = typename TImage::RegionType
 
using Self = ImageConstIteratorWithOnlyIndex
 
using SizeType = typename TImage::SizeType
 
using SizeValueType = typename SizeType::SizeValueType
 

Public Member Functions

 ImageRegionConstIteratorWithOnlyIndex ()
 
 ImageRegionConstIteratorWithOnlyIndex (const TImage *ptr, const RegionType &region)
 
 ImageRegionConstIteratorWithOnlyIndex (const ImageConstIteratorWithOnlyIndex< TImage > &it)
 
Selfoperator++ ()
 
Selfoperator-- ()
 
- Public Member Functions inherited from itk::ImageConstIteratorWithOnlyIndex< TImage >
const IndexTypeGetIndex () const
 
const RegionTypeGetRegion () const
 
void GoToBegin ()
 
void GoToReverseBegin ()
 
 ImageConstIteratorWithOnlyIndex ()
 
 ImageConstIteratorWithOnlyIndex (const Self &it)
 
 ImageConstIteratorWithOnlyIndex (const TImage *ptr, const RegionType &region)
 
bool IsAtEnd () const
 
bool IsAtReverseEnd () const
 
bool operator!= (const Self &it) const
 
bool operator< (const Self &it) const
 
bool operator<= (const Self &it) const
 
Selfoperator= (const Self &it)
 
bool operator== (const Self &it) const
 
bool operator> (const Self &it) const
 
bool operator>= (const Self &it) const
 
bool Remaining ()
 
void SetIndex (const IndexType &ind)
 
virtual ~ImageConstIteratorWithOnlyIndex ()=default
 

Additional Inherited Members

- Static Public Member Functions inherited from itk::ImageConstIteratorWithOnlyIndex< TImage >
static unsigned int GetImageDimension ()
 
- Static Public Attributes inherited from itk::ImageConstIteratorWithOnlyIndex< TImage >
static constexpr unsigned int ImageDimension = TImage::ImageDimension
 
- Protected Attributes inherited from itk::ImageConstIteratorWithOnlyIndex< TImage >
IndexType m_BeginIndex
 
IndexType m_EndIndex
 
TImage::ConstPointer m_Image
 
OffsetValueType m_OffsetTable [ImageDimension+1]
 
IndexType m_PositionIndex
 
RegionType m_Region
 
bool m_Remaining
 

Member Typedef Documentation

template<typename TImage >
using itk::ImageRegionConstIteratorWithOnlyIndex< TImage >::ImageType = typename Superclass::ImageType

Definition at line 147 of file itkImageRegionConstIteratorWithOnlyIndex.h.

template<typename TImage >
using itk::ImageRegionConstIteratorWithOnlyIndex< TImage >::IndexType = typename Superclass::IndexType

Index type alias support While these were already typdef'ed in the superclass they need to be redone here for this subclass to compile properly with gcc.Types inherited from the Superclass

Definition at line 143 of file itkImageRegionConstIteratorWithOnlyIndex.h.

template<typename TImage >
using itk::ImageRegionConstIteratorWithOnlyIndex< TImage >::OffsetType = typename Superclass::OffsetType

Definition at line 145 of file itkImageRegionConstIteratorWithOnlyIndex.h.

template<typename TImage >
using itk::ImageRegionConstIteratorWithOnlyIndex< TImage >::RegionType = typename Superclass::RegionType

Definition at line 146 of file itkImageRegionConstIteratorWithOnlyIndex.h.

Standard class type aliases.

Definition at line 134 of file itkImageRegionConstIteratorWithOnlyIndex.h.

template<typename TImage >
using itk::ImageRegionConstIteratorWithOnlyIndex< TImage >::SizeType = typename Superclass::SizeType

Definition at line 144 of file itkImageRegionConstIteratorWithOnlyIndex.h.

template<typename TImage >
using itk::ImageRegionConstIteratorWithOnlyIndex< TImage >::Superclass = ImageConstIteratorWithOnlyIndex< TImage >

Definition at line 135 of file itkImageRegionConstIteratorWithOnlyIndex.h.

Constructor & Destructor Documentation

Default constructor. Needed since we provide a cast constructor.

Definition at line 150 of file itkImageRegionConstIteratorWithOnlyIndex.h.

template<typename TImage >
itk::ImageRegionConstIteratorWithOnlyIndex< TImage >::ImageRegionConstIteratorWithOnlyIndex ( const TImage *  ptr,
const RegionType region 
)
inline

Constructor establishes an iterator to walk a particular image and a particular region of that image.

Definition at line 154 of file itkImageRegionConstIteratorWithOnlyIndex.h.

template<typename TImage >
itk::ImageRegionConstIteratorWithOnlyIndex< TImage >::ImageRegionConstIteratorWithOnlyIndex ( const ImageConstIteratorWithOnlyIndex< TImage > &  it)
inline

Constructor that can be used to cast from an ImageIterator to an ImageRegionConstIteratorWithOnlyIndex. Many routines return an ImageIterator but for a particular task, you may want an ImageRegionConstIteratorWithOnlyIndex. Rather than provide overloaded APIs that return different types of Iterators, itk returns ImageIterators and uses constructors to cast from an ImageIterator to a ImageRegionConstIteratorWithOnlyIndex.

Definition at line 163 of file itkImageRegionConstIteratorWithOnlyIndex.h.

References itk::ImageConstIteratorWithOnlyIndex< TImage >::operator=().

Member Function Documentation

template<typename TImage >
Self& itk::ImageRegionConstIteratorWithOnlyIndex< TImage >::operator++ ( )

Increment (prefix) the fastest moving dimension of the iterator's index. This operator will constrain the iterator within the region (i.e. the iterator will automatically wrap from the end of the row of the region to the beginning of the next row of the region) up until the iterator tries to moves past the last pixel of the region. Here, the iterator will be set to be one pixel past the end of the region.

See Also
operator--
template<typename TImage >
Self& itk::ImageRegionConstIteratorWithOnlyIndex< TImage >::operator-- ( )

Decrement (prefix) the fastest moving dimension of the iterator's index. This operator will constrain the iterator within the region (i.e. the iterator will automatically wrap from the beginning of the row of the region to the end of the previous row of the region) up until the iterator tries to moves past the first pixel of the region. Here, the iterator will be set to be one pixel past the beginning of the region.

See Also
operator++

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