#include <itkImageRandomConstIteratorWithIndex.h>

Detailed Description

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

A multi-dimensional image iterator that visits a random set of pixels within an image region.

ImageRandomConstIteratorWithIndex is a multi-dimensional iterator class that is templated over image type. ImageRandomConstIteratorWithIndex is constrained to walk only within the specified region. It samples random pixel positions at each increment or decrement.

ImageRandomConstIteratorWithIndex 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.

The operator++ method provides a simple syntax for walking around a region of a multidimensional image. operator++ performs a jump to a random position within the specified image region. This is designed to facilitate the extraction of random samples from the image.

This is the typical use of this iterator in a loop:

ImageRandomConstIteratorWithIndex<ImageType> it( image, image->GetRequestedRegion() );
 
it.SetNumberOfSamples(200);
it.GoToBegin();
while( !it.IsAtEnd() )
{
  it.Get();
  ++it;  // here it jumps to another random position inside the region
 }

or

ImageRandomConstIteratorWithIndex<ImageType> it( image, image->GetRequestedRegion() );
 
it.SetNumberOfSamples(200);
it.GoToEnd();
while( !it.IsAtBegin() )
{
  it.Get();
  --it;  // here it jumps to another random position inside the region
 }

Warning: Incrementing the iterator (++it) followed by a decrement (–it) or vice versa does not in general return the iterator to the same position.

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

ITK Sphinx Examples:

All ITK Sphinx Examples

Random Selection Of Pixels From Region

Examples: Examples/Iterators/ImageRandomConstIteratorWithIndex.cxx, SphinxExamples/src/Core/Common/RandomSelectOfPixelsFromRegion/Code.cxx, and SphinxExamples/src/IO/ImageBase/ConvertImageToAnotherType/Code.cxx.

Definition at line 116 of file itkImageRandomConstIteratorWithIndex.h.

Inheritance diagram for itk::ImageRandomConstIteratorWithIndex< TImage >:

Collaboration diagram for itk::ImageRandomConstIteratorWithIndex< TImage >:

Public Types
using	AccessorType = typename TImage::AccessorType

using	ImageType = TImage

using	IndexType = typename TImage::IndexType

using	IndexValueType = typename IndexType::IndexValueType

using	InternalPixelType = typename TImage::InternalPixelType

using	OffsetType = typename TImage::OffsetType

using	OffsetValueType = typename OffsetType::OffsetValueType

using	PixelContainer = typename TImage::PixelContainer

using	PixelContainerPointer = typename PixelContainer::Pointer

using	PixelType = typename TImage::PixelType

using	RegionType = typename TImage::RegionType

using	Self = ImageRandomConstIteratorWithIndex

using	SizeType = typename TImage::SizeType

using	SizeValueType = typename SizeType::SizeValueType

using	Superclass = ImageConstIteratorWithIndex< TImage >

Public Types inherited from itk::ImageConstIteratorWithIndex< TImage >
using	AccessorFunctorType = typename TImage::AccessorFunctorType

using	AccessorType = typename TImage::AccessorType

using	ImageType = TImage

using	IndexType = typename TImage::IndexType

using	IndexValueType = typename IndexType::IndexValueType

using	InternalPixelType = typename TImage::InternalPixelType

using	OffsetType = typename TImage::OffsetType

using	OffsetValueType = typename OffsetType::OffsetValueType

using	PixelContainer = typename TImage::PixelContainer

using	PixelContainerPointer = typename PixelContainer::Pointer

using	PixelType = typename TImage::PixelType

using	RegionType = typename TImage::RegionType

using	Self = ImageConstIteratorWithIndex

using	SizeType = typename TImage::SizeType

using	SizeValueType = typename SizeType::SizeValueType

Public Member Functions
SizeValueType	GetNumberOfSamples () const

	ImageRandomConstIteratorWithIndex (const ImageConstIteratorWithIndex< TImage > &it)

	ImageRandomConstIteratorWithIndex (const ImageType *ptr, const RegionType &region)

bool	IsAtBegin () const

bool	IsAtEnd () const

void	ReinitializeSeed ()

void	ReinitializeSeed (int)

void	SetNumberOfSamples (SizeValueType number)


	ImageRandomConstIteratorWithIndex ()=default

	~ImageRandomConstIteratorWithIndex () override=default


void	GoToBegin ()


void	GoToEnd ()


Self &	operator++ ()


Self &	operator-- ()

Public Member Functions inherited from itk::ImageConstIteratorWithIndex< TImage >
PixelType	Get () const

const IndexType &	GetIndex () const

const RegionType &	GetRegion () const

void	GoToBegin ()

void	GoToReverseBegin ()

	ImageConstIteratorWithIndex ()=default

	ImageConstIteratorWithIndex (const Self &it)

	ImageConstIteratorWithIndex (const TImage *ptr, const RegionType &region)

bool	IsAtEnd () const

bool	IsAtReverseEnd () const

	ITK_UNEQUAL_OPERATOR_MEMBER_FUNCTION (Self)

bool	operator< (const Self &it) const

bool	operator<= (const Self &it) const

Self &	operator= (const Self &it)

bool	operator== (const Self &it) const

bool	operator> (const Self &it) const

bool	operator>= (const Self &it) const

bool	Remaining ()

const PixelType &	Value () const

virtual	~ImageConstIteratorWithIndex ()=default

void	SetIndex (const IndexType &ind)

Private Types
using	GeneratorPointer = typename Statistics::MersenneTwisterRandomVariateGenerator::Pointer

Private Member Functions
void	RandomJump ()

Private Attributes
GeneratorPointer	m_Generator { Statistics::MersenneTwisterRandomVariateGenerator::New() }

SizeValueType	m_NumberOfPixelsInRegion {}

SizeValueType	m_NumberOfSamplesDone {}

SizeValueType	m_NumberOfSamplesRequested {}

Additional Inherited Members
Static Public Member Functions inherited from itk::ImageConstIteratorWithIndex< TImage >
static constexpr unsigned int	GetImageDimension ()

Static Public Attributes inherited from itk::ImageConstIteratorWithIndex< TImage >
static constexpr unsigned int	ImageDimension = TImage::ImageDimension

Protected Attributes inherited from itk::ImageConstIteratorWithIndex< TImage >
const InternalPixelType *	m_Begin { nullptr }

IndexType	m_BeginIndex { { 0 } }

const InternalPixelType *	m_End { nullptr }

IndexType	m_EndIndex { { 0 } }

TImage::ConstWeakPointer	m_Image {}

OffsetValueType	m_OffsetTable [ImageDimension+1] {}

AccessorType	m_PixelAccessor {}

AccessorFunctorType	m_PixelAccessorFunctor {}

const InternalPixelType *	m_Position { nullptr }

IndexType	m_PositionIndex { { 0 } }

RegionType	m_Region {}

bool	m_Remaining { false }

Member Typedef Documentation

◆ AccessorType

template<typename TImage>

using itk::ImageConstIteratorWithIndex< TImage >::AccessorType = typename TImage::AccessorType

Accessor type that converts data between internal and external representations.

Definition at line 132 of file itkImageConstIteratorWithIndex.h.

◆ GeneratorPointer

template<typename TImage>

using itk::ImageRandomConstIteratorWithIndex< TImage >::GeneratorPointer = typename Statistics::MersenneTwisterRandomVariateGenerator::Pointer

private

Definition at line 237 of file itkImageRandomConstIteratorWithIndex.h.

◆ ImageType

template<typename TImage>

using itk::ImageConstIteratorWithIndex< TImage >::ImageType = TImage

Image type alias support

Definition at line 116 of file itkImageConstIteratorWithIndex.h.

◆ IndexType

template<typename TImage>

using itk::ImageConstIteratorWithIndex< TImage >::IndexType = typename TImage::IndexType

Index type alias support

Definition at line 105 of file itkImageConstIteratorWithIndex.h.

◆ IndexValueType

template<typename TImage>

using itk::ImageConstIteratorWithIndex< TImage >::IndexValueType = typename IndexType::IndexValueType

Definition at line 106 of file itkImageConstIteratorWithIndex.h.

◆ InternalPixelType

template<typename TImage>

using itk::ImageConstIteratorWithIndex< TImage >::InternalPixelType = typename TImage::InternalPixelType

Internal Pixel Type

Definition at line 125 of file itkImageConstIteratorWithIndex.h.

◆ OffsetType

template<typename TImage>

using itk::ImageConstIteratorWithIndex< TImage >::OffsetType = typename TImage::OffsetType

Type of the Offset taken from the image

Definition at line 136 of file itkImageConstIteratorWithIndex.h.

◆ OffsetValueType

template<typename TImage>

using itk::ImageConstIteratorWithIndex< TImage >::OffsetValueType = typename OffsetType::OffsetValueType

Definition at line 137 of file itkImageConstIteratorWithIndex.h.

◆ PixelContainer

template<typename TImage>

using itk::ImageConstIteratorWithIndex< TImage >::PixelContainer = typename TImage::PixelContainer

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

Definition at line 121 of file itkImageConstIteratorWithIndex.h.

◆ PixelContainerPointer

template<typename TImage>

using itk::ImageConstIteratorWithIndex< TImage >::PixelContainerPointer = typename PixelContainer::Pointer

Definition at line 122 of file itkImageConstIteratorWithIndex.h.

◆ PixelType

template<typename TImage>

using itk::ImageConstIteratorWithIndex< TImage >::PixelType = typename TImage::PixelType

External Pixel Type

Definition at line 128 of file itkImageConstIteratorWithIndex.h.

◆ RegionType

template<typename TImage>

using itk::ImageConstIteratorWithIndex< TImage >::RegionType = typename TImage::RegionType

Region type alias support

Definition at line 113 of file itkImageConstIteratorWithIndex.h.

◆ Self

template<typename TImage>

using itk::ImageRandomConstIteratorWithIndex< TImage >::Self = ImageRandomConstIteratorWithIndex

Standard class type aliases.

Definition at line 120 of file itkImageRandomConstIteratorWithIndex.h.

◆ SizeType

template<typename TImage>

using itk::ImageConstIteratorWithIndex< TImage >::SizeType = typename TImage::SizeType

Size type alias support

Definition at line 109 of file itkImageConstIteratorWithIndex.h.

◆ SizeValueType

template<typename TImage>

using itk::ImageConstIteratorWithIndex< TImage >::SizeValueType = typename SizeType::SizeValueType

Definition at line 110 of file itkImageConstIteratorWithIndex.h.

◆ Superclass

template<typename TImage>

using itk::ImageRandomConstIteratorWithIndex< TImage >::Superclass = ImageConstIteratorWithIndex<TImage>

Definition at line 121 of file itkImageRandomConstIteratorWithIndex.h.

Constructor & Destructor Documentation

◆ ImageRandomConstIteratorWithIndex() [1/3]

template<typename TImage>

itk::ImageRandomConstIteratorWithIndex< TImage >::ImageRandomConstIteratorWithIndex ( )

default

Default constructor. Needed since we provide a cast constructor.

◆ ~ImageRandomConstIteratorWithIndex()

template<typename TImage>

itk::ImageRandomConstIteratorWithIndex< TImage >::~ImageRandomConstIteratorWithIndex ( )

overridedefault

Default constructor. Needed since we provide a cast constructor.

◆ ImageRandomConstIteratorWithIndex() [2/3]

template<typename TImage>

itk::ImageRandomConstIteratorWithIndex< TImage >::ImageRandomConstIteratorWithIndex	(	const ImageType *	ptr,
		const RegionType &	region
	)

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

◆ ImageRandomConstIteratorWithIndex() [3/3]

template<typename TImage>

itk::ImageRandomConstIteratorWithIndex< TImage >::ImageRandomConstIteratorWithIndex ( const ImageConstIteratorWithIndex< TImage > & it )

inline

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

Definition at line 153 of file itkImageRandomConstIteratorWithIndex.h.

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