Alter an image with shot noise. More...

#include <sitkShotNoiseImageFilter.h>

Inheritance diagram for itk::simple::ShotNoiseImageFilter:

Collaboration diagram for itk::simple::ShotNoiseImageFilter:

Public Types
typedef BasicPixelIDTypeList	PixelIDTypeList

typedef ShotNoiseImageFilter	Self

Public Types inherited from itk::simple::ImageFilter< 1 >
typedef ImageFilter	Self

Public Types inherited from itk::simple::ProcessObject
typedef ProcessObject	Self

Public Member Functions
Image	Execute (const Image &image1)

Image	Execute (const Image &image1, double scale, uint32_t seed)

std::string	GetName () const

double	GetScale () const

uint32_t	GetSeed () const

Self &	SetScale (double Scale)

Self &	SetSeed (uint32_t Seed)

	ShotNoiseImageFilter ()

std::string	ToString () const

virtual	~ShotNoiseImageFilter ()

Public Member Functions inherited from itk::simple::ImageFilter< 1 >
	ImageFilter ()

virtual	~ImageFilter ()=0

Public Member Functions inherited from itk::simple::ProcessObject
virtual void	Abort ()

virtual int	AddCommand (itk::simple::EventEnum event, itk::simple::Command &cmd)
	Add a Command Object to observer the event. More...

virtual float	GetProgress () const
	An Active Measurement of the progress of execution. More...

virtual bool	HasCommand (itk::simple::EventEnum event) const
	Query of this object has any registered commands for event. More...

	ProcessObject ()

virtual void	RemoveAllCommands ()
	Remove all registered commands. More...

virtual	~ProcessObject ()

virtual void	DebugOn ()

virtual void	DebugOff ()

virtual bool	GetDebug () const

virtual void	SetDebug (bool debugFlag)

virtual void	SetNumberOfThreads (unsigned int n)

virtual unsigned int	GetNumberOfThreads () const

Private Types
typedef Image(Self::*	MemberFunctionType) (const Image &image1)

Private Member Functions
template<class TImageType >
Image	ExecuteInternal (const Image &image1)

template<class TImageType >
Image	ExecuteInternalVectorImage (const Image &image)

Private Attributes
nsstd::auto_ptr< detail::MemberFunctionFactory< MemberFunctionType > >	m_MemberFactory

double	m_Scale

uint32_t	m_Seed

Friends
struct	detail::ExecuteInternalVectorImageAddressor< MemberFunctionType >

struct	detail::MemberFunctionAddressor< MemberFunctionType >

Additional Inherited Members
Static Public Member Functions inherited from itk::simple::ProcessObject
static bool	GetGlobalDefaultDebug ()

static void	GlobalDefaultDebugOff ()

static void	GlobalDefaultDebugOn ()

static void	SetGlobalDefaultDebug (bool debugFlag)

static void	GlobalWarningDisplayOn ()

static void	GlobalWarningDisplayOff ()

static void	SetGlobalWarningDisplay (bool flag)

static bool	GetGlobalWarningDisplay ()

static void	SetGlobalDefaultNumberOfThreads (unsigned int n)

static unsigned int	GetGlobalDefaultNumberOfThreads ()

static double	GetGlobalDefaultCoordinateTolerance ()
	Access the global tolerance to determine congruent spaces. More...

static void	SetGlobalDefaultCoordinateTolerance (double)
	Access the global tolerance to determine congruent spaces. More...

static double	GetGlobalDefaultDirectionTolerance ()
	Access the global tolerance to determine congruent spaces. More...

static void	SetGlobalDefaultDirectionTolerance (double)
	Access the global tolerance to determine congruent spaces. More...

Protected Member Functions inherited from itk::simple::ProcessObject
virtual unsigned long	AddITKObserver (const itk::EventObject &, itk::Command *)

virtual itk::ProcessObject *	GetActiveProcess ()

virtual void	OnActiveProcessDelete ()

virtual void	onCommandDelete (const itk::simple::Command *cmd) SITK_NOEXCEPT

virtual void	PreUpdate (itk::ProcessObject *p)

virtual void	RemoveITKObserver (EventCommand &e)

Protected Member Functions inherited from itk::simple::NonCopyable
	NonCopyable ()

Static Protected Member Functions inherited from itk::simple::ImageFilter< 1 >
static void	FixNonZeroIndex (TImageType *img)

Static Protected Member Functions inherited from itk::simple::ProcessObject
template<class TImageType >
static TImageType::ConstPointer	CastImageToITK (const Image &img)

template<class TImageType >
static Image	CastITKToImage (TImageType *img)

template<class TPixelType , unsigned int VImageDimension, unsigned int VLength, template< typename, unsigned int > class TVector>
static Image	CastITKToImage (itk::Image< TVector< TPixelType, VLength >, VImageDimension > *img)

static const itk::EventObject &	GetITKEventObject (EventEnum e)

template<typename T >
static std::ostream &	ToStringHelper (std::ostream &os, const T &v)

static std::ostream &	ToStringHelper (std::ostream &os, const char &v)

static std::ostream &	ToStringHelper (std::ostream &os, const signed char &v)

static std::ostream &	ToStringHelper (std::ostream &os, const unsigned char &v)

Detailed Description

Alter an image with shot noise.

The shot noise follows a Poisson distribution:

: where is a Poisson-distributed random variable of mean . The noise is thus dependent on the pixel intensities in the image.

The intensities in the image can be scaled by a user provided value to map pixel values to the actual number of particles. The scaling can be seen as the inverse of the gain used during the acquisition. The noisy signal is then scaled back to its input intensity range:

: $I = \frac{N(I_0 \times s)}{s}$

: where is the scale factor.

The Poisson-distributed variable $\lambda$ is computed by using the algorithm:

: $\begin{array}{l} k \leftarrow 0 \\ p \leftarrow 1 \\ \textbf{repeat} \\ \left\{ \begin{array}{l} k \leftarrow k+1 \\ p \leftarrow p \ast U() \end{array} \right. \\ \textbf{until } p > e^{\lambda} \\ \textbf{return} (k) \end{array}$

: where provides a uniformly distributed random variable in the interval .

This algorithm is very inefficient for large values of $\lambda$ , though. Fortunately, the Poisson distribution can be accurately approximated by a Gaussian distribution of mean and variance $\lambda$ when $\lambda$ is large enough. In this implementation, this value is considered to be 50. This leads to the faster algorithm:

: $\lambda + \sqrt{\lambda} \times N()$

: where is a normally distributed random variable of mean 0 and variance 1.

Author: Gaetan Lehmann

This code was contributed in the Insight Journal paper "Noise Simulation". https://hdl.handle.net/10380/3158

See also: itk::simple::ShotNoise for the procedural interface; itk::ShotNoiseImageFilter for the Doxygen on the original ITK class.

Definition at line 77 of file sitkShotNoiseImageFilter.h.

Member Typedef Documentation

typedef Image(Self::* itk::simple::ShotNoiseImageFilter::MemberFunctionType) (const Image &image1)

private

Setup for member function dispatching

Definition at line 128 of file sitkShotNoiseImageFilter.h.

typedef BasicPixelIDTypeList itk::simple::ShotNoiseImageFilter::PixelIDTypeList

Define the pixels types supported by this filter

Definition at line 89 of file sitkShotNoiseImageFilter.h.

typedef ShotNoiseImageFilter itk::simple::ShotNoiseImageFilter::Self

Definition at line 79 of file sitkShotNoiseImageFilter.h.

Constructor & Destructor Documentation

virtual itk::simple::ShotNoiseImageFilter::~ShotNoiseImageFilter ( )

virtual

Destructor

itk::simple::ShotNoiseImageFilter::ShotNoiseImageFilter ( )

Default Constructor that takes no arguments and initializes default parameters

Member Function Documentation

Image itk::simple::ShotNoiseImageFilter::Execute ( const Image & image1 )

Execute the filter on the input image

Image itk::simple::ShotNoiseImageFilter::Execute	(	const Image &	image1,
		double	scale,
		uint32_t	seed
	)

Execute the filter on the input image with the given parameters

template<class TImageType >

Image itk::simple::ShotNoiseImageFilter::ExecuteInternal ( const Image & image1 )

private

template<class TImageType >

Image itk::simple::ShotNoiseImageFilter::ExecuteInternalVectorImage ( const Image & image )

private

Dispatched methods which calls ExecuteInteral on each component

std::string itk::simple::ShotNoiseImageFilter::GetName ( ) const

inlinevirtual

Name of this class

Implements itk::simple::ProcessObject.

Definition at line 111 of file sitkShotNoiseImageFilter.h.

double itk::simple::ShotNoiseImageFilter::GetScale ( ) const

inline

Set/Get the value to map the pixel value to the actual particle counting. The scaling can be seen as the inverse of the gain used during the acquisition. The noisy signal is then scaled back to its input intensity range. Defaults to 1.0.

Definition at line 101 of file sitkShotNoiseImageFilter.h.

uint32_t itk::simple::ShotNoiseImageFilter::GetSeed ( ) const

inline

Definition at line 109 of file sitkShotNoiseImageFilter.h.

Self& itk::simple::ShotNoiseImageFilter::SetScale ( double Scale )

inline

Set/Get the value to map the pixel value to the actual particle counting. The scaling can be seen as the inverse of the gain used during the acquisition. The noisy signal is then scaled back to its input intensity range. Defaults to 1.0.

Definition at line 96 of file sitkShotNoiseImageFilter.h.

Self& itk::simple::ShotNoiseImageFilter::SetSeed ( uint32_t Seed )

inline

Definition at line 105 of file sitkShotNoiseImageFilter.h.

std::string itk::simple::ShotNoiseImageFilter::ToString ( ) const

virtual

Print ourselves out

Reimplemented from itk::simple::ProcessObject.