GammaFunctor Class Reference

Gamma correction. Intensity is mapped as f' = f^(gamma) More...

#include <FunctorPack.h>

Inheritance diagram for GammaFunctor:

Collaboration diagram for GammaFunctor:

Public Member Functions
	GammaFunctor (double gamma=1.0)
	GammaFunctor (const GammaFunctor &ftor)
double	operator() (double s) const
Public Member Functions inherited from UnaryFunctor
	UnaryFunctor (const std::string &name, const std::string &description="", double scale=1.0, double bias=0.0)
Public Member Functions inherited from Functor
void	setScale (double scale, double bias=0.0)
virtual void	updateBean () const override
	Called after setParameters()
Public Member Functions inherited from BeanLike
	BeanLike (const BeanLike &b)
	Copy constructor. Re-links parameters to the member variables of this (new) instance.
	BeanLike (const std::string &name, const std::string &description="")
	Constructor.
virtual const std::string &	getName () const
	Return the name of an instance.
virtual const std::string &	getDescription () const
	Return a brief description.
bool	hasParameters () const
	Tells if any parameters have been linked (registered) for this bean.
template<class F >
F	getParameter (const std::string &p) const
	Gets a single parameter.
const map_t &	getParameters () const
	Returns the parameter map (const access).
map_t &	getParameters ()
	Returns the parameter map.
template<class F >
void	setParametersFromEntries (const F &args)
	Sets several parameters at once from a sequence of key-value pairs.
void	setParameters (std::initializer_list< Variable::init_pair_t > args)
	Grants access to (if above hidden)
virtual void	setParameters (const std::string &p, char assignmentSymbol='=', char separatorSymbol=0)
	Sets comma-separated parameters in a predetermined order "a,b,c" or by specifing them "b=2".
template<class T >
void	setParameters (const std::map< std::string, T > &args)
	Set parameters.
template<class T >
void	setParameters (const SmartMap< T > &args)
	Set parameters.
void	setParameter (const std::string &p, const Castable &value)
	Sets a single parameter.
template<class T >
void	setParameter (const std::string &p, const VariableT< T > &value)
template<class F >
void	setParameter (const std::string &p, const F &value)
	Sets a single parameter.
template<class F >
void	setParameter (const std::string &p, std::initializer_list< F > value)
	Sets a single parameter.
BeanLike &	operator= (const BeanLike &b)
	Assigns the parameter values of another bean (by key) to this one's own parameters.
virtual std::ostream &	toStream (std::ostream &ostr, bool compact=true) const
	Prints the name, description and current parameter values.

Public Attributes
double	gamma = 1.0

Additional Inherited Members
Public Types inherited from BeanLike
typedef ReferenceMap	map_t
	Reference map type used to store this bean's parameters (name -> linked variable).
Protected Member Functions inherited from Functor
	Functor (const std::string &name, const std::string &description="", double scale=1.0, double bias=0.0)
	Functor (const Functor &fct)
virtual void	updateScale () const
Protected Member Functions inherited from BeanLike
virtual void	storeLastArguments (const std::string &p)
	Called after setParameters()
Protected Attributes inherited from Functor
double	scale
	Relative scale, typically 1. Optional.
double	bias
	"Relative" bias, typically 0. Optional.
double	scaleFinal
	Scaling factor after encodings of src and dst images are known.
double	biasFinal
	Scaling factor after encodings of src and dst images are known.
Protected Attributes inherited from BeanLike
const std::string	name
	Name of this bean, typically also the name of the (derived) class.
const std::string	description
	Brief, human-readable description of this bean.
map_t	parameters
	Parameters (name -> linked variable), typically linked to member variables of the derived class.

Detailed Description

Gamma correction. Intensity is mapped as f' = f^(gamma)

Adjusts the brightness such that intensities remain monotonously inside the original scale. Unlike in direct linear scaling neither underflow nor overflow occurs and visual details remain detectable down to applied bit resolution.

Prior to calling this function it should be ensured that the source image has normalized scale (eg. with –physicalRange, -R ).

drainage image-gray.png -R 0:1 --iGamma 1.5 -o gamma-bright.png
drainage image-gray.png -R 0:1 --iGamma 2.0 -o gamma-bright.png
drainage image-gray.png -R 0:1 --iGamma 0.5 -o gamma-dark.png

drainage image-color.png -R 0:1 --iGamma 2.0 -o gamma-color-bright.png
drainage image-color.png -R 0:1 --iGamma 0.5 -o gamma-color-dark.png

See also

FunctorOp

NOTE. Design for parameters may vary in future, since multichannel image could be handled by giving a value for each: 1.2,1.4,0.7 for example.

Member Function Documentation

operator()()

double operator() ( double  s ) const

inlinevirtual

Implements UnaryFunctor.

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

• src/drain/util/FunctorPack.h