ITK  4.1.0
Insight Segmentation and Registration Toolkit
Public Types | Public Member Functions
itk::ImageRegionConstIteratorWithIndex< TImage > Class Template Reference

#include <itkImageRegionConstIteratorWithIndex.h>

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

List of all members.

Public Types

typedef Superclass::AccessorType AccessorType
typedef Superclass::ImageType ImageType
typedef Superclass::IndexType IndexType
typedef
Superclass::InternalPixelType 
InternalPixelType
typedef Superclass::OffsetType OffsetType
typedef Superclass::PixelContainer PixelContainer
typedef
Superclass::PixelContainerPointer 
PixelContainerPointer
typedef Superclass::PixelType PixelType
typedef Superclass::RegionType RegionType
typedef
ImageRegionConstIteratorWithIndex 
Self
typedef Superclass::SizeType SizeType
typedef
ImageConstIteratorWithIndex
< TImage > 
Superclass

Public Member Functions

 ImageRegionConstIteratorWithIndex ()
 ImageRegionConstIteratorWithIndex (const TImage *ptr, const RegionType &region)
 ImageRegionConstIteratorWithIndex (const ImageConstIteratorWithIndex< TImage > &it)
Selfoperator++ ()
Selfoperator-- ()

Detailed Description

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

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

The "WithIndex" family of iteators was designed for algorithms that use both the values and locations of image pixels in calculations. Unlike ImageRegionIterator, which calculates an index only when requested, ImageRegionIteratorWithIndex 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.

ImageRegionConstIteratorWithIndex 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 buffer, the size of the region, the start index of the buffer, and the start index of the region. To gain access to this information, ImageRegionConstIteratorWithIndex holds a reference to the image over which it is traversing.

ImageRegionConstIteratorWithIndex 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() )
  {
    it.Set( 100.0 + it.Get() );
    ++it;
  }

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

  IteratorType it( image, image->GetRequestedRegion() );

  it.End();

  while( !it.IsAtBegin() )
  {
    it.Set( 100.0 );
    --it;
  }
MORE INFORMATION
Examples:
itkVectorImageTest.cxx.

Definition at line 130 of file itkImageRegionConstIteratorWithIndex.h.


Member Typedef Documentation

template<typename TImage>
typedef Superclass::ImageType itk::ImageRegionConstIteratorWithIndex< TImage >::ImageType
template<typename TImage>
typedef Superclass::IndexType itk::ImageRegionConstIteratorWithIndex< TImage >::IndexType

Index typedef 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

Reimplemented from itk::ImageConstIteratorWithIndex< TImage >.

Reimplemented in itk::ImageRegionExclusionConstIteratorWithIndex< TImage >, itk::ImageRegionIteratorWithIndex< TImage >, and itk::ImageRegionExclusionIteratorWithIndex< TImage >.

Definition at line 143 of file itkImageRegionConstIteratorWithIndex.h.

template<typename TImage>
typedef Superclass::OffsetType itk::ImageRegionConstIteratorWithIndex< TImage >::OffsetType

PixelContainer typedef support. Used to refer to the container for the pixel data. While this was already typdef'ed in the superclass, it needs to be redone here for this subclass to compile properly with gcc.

Reimplemented from itk::ImageConstIteratorWithIndex< TImage >.

Reimplemented in itk::ImageRegionExclusionConstIteratorWithIndex< TImage >, itk::ImageRegionIteratorWithIndex< TImage >, and itk::ImageRegionExclusionIteratorWithIndex< TImage >.

Definition at line 148 of file itkImageRegionConstIteratorWithIndex.h.

template<typename TImage>
typedef Superclass::PixelType itk::ImageRegionConstIteratorWithIndex< TImage >::PixelType
template<typename TImage>
typedef Superclass::RegionType itk::ImageRegionConstIteratorWithIndex< TImage >::RegionType
template<typename TImage>
typedef Superclass::SizeType itk::ImageRegionConstIteratorWithIndex< TImage >::SizeType
template<typename TImage>
typedef ImageConstIteratorWithIndex< TImage > itk::ImageRegionConstIteratorWithIndex< TImage >::Superclass

Constructor & Destructor Documentation

template<typename TImage>
itk::ImageRegionConstIteratorWithIndex< TImage >::ImageRegionConstIteratorWithIndex ( ) [inline]

Default constructor. Needed since we provide a cast constructor.

Definition at line 155 of file itkImageRegionConstIteratorWithIndex.h.

template<typename TImage>
itk::ImageRegionConstIteratorWithIndex< TImage >::ImageRegionConstIteratorWithIndex ( 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 159 of file itkImageRegionConstIteratorWithIndex.h.

template<typename TImage>
itk::ImageRegionConstIteratorWithIndex< TImage >::ImageRegionConstIteratorWithIndex ( const ImageConstIteratorWithIndex< TImage > &  it) [inline]

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

Definition at line 169 of file itkImageRegionConstIteratorWithIndex.h.


Member Function Documentation

template<typename TImage>
Self& itk::ImageRegionConstIteratorWithIndex< 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--

Reimplemented in itk::ImageRegionExclusionConstIteratorWithIndex< TImage >.

template<typename TImage>
Self& itk::ImageRegionConstIteratorWithIndex< 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++

Reimplemented in itk::ImageRegionExclusionConstIteratorWithIndex< TImage >.


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