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details VectorComponentAccessor< VECTORTYPE > Class Template Reference VIGRA

Accessor for one component of a vector. More...

#include <vigra/accessor.hxx>

Public Types

typedef VECTORTYPE::value_type value_type
 

Public Member Functions

template<class ITERATOR >
value_type const & operator() (ITERATOR const &i) const
 
template<class ITERATOR , class OFFSET >
value_type const & operator() (ITERATOR const &i, OFFSET const &diff) const
 
template<class V , class ITERATOR >
void set (V const &value, ITERATOR const &i) const
 
template<class V , class ITERATOR , class OFFSET >
void set (V const &value, ITERATOR const &i, OFFSET const &diff) const
 
void setIndex (int i)
 
 VectorComponentAccessor (int index)
 

Detailed Description

template<class VECTORTYPE>
class vigra::VectorComponentAccessor< VECTORTYPE >

Accessor for one component of a vector.

This accessor allows to select a single component (a single 'band') of a vector valued pixel type. The pixel type must support operator[]. The index of the component to be selected is passed in the constructor. The accessor returns its items by reference. If you want to pass/return items by value, use VectorComponentValueAccessor. If a floating point number is assigned by means of an accessor with integral value_type, the value is rounded and clipped as appropriate.

Usage:

vigra::BRGBImage image(w,h);
// init red channel with 255
initImage(destImageRange(image,
VectorComponentAccessor<vigra::BRGBImage::value_type>(0)),
255);

#include <vigra/accessor.hxx>
Namespace: vigra

Member Typedef Documentation

typedef VECTORTYPE::value_type value_type

the value_type

Constructor & Destructor Documentation

VectorComponentAccessor ( int  index)

determine the component to be accessed

Member Function Documentation

value_type const& operator() ( ITERATOR const &  i) const

read the current data item

value_type const& operator() ( ITERATOR const &  i,
OFFSET const &  diff 
) const

read the data item at an offset (can be 1D or 2D or higher order difference).

void set ( V const &  value,
ITERATOR const &  i 
) const

Write the current data item. The type V of the passed in value is automatically converted to value_type. In case of a conversion floating point -> integral this includes rounding and clipping.

void set ( V const &  value,
ITERATOR const &  i,
OFFSET const &  diff 
) const

Write the data item at an offset (can be 1D or 2D or higher order difference).. The type V of the passed in value is automatically converted to value_type. In case of a conversion floating point -> integral this includes rounding and clipping.

void setIndex ( int  i)

Reset the index to the given number.


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

© Ullrich Köthe (ullrich.koethe@iwr.uni-heidelberg.de)
Heidelberg Collaboratory for Image Processing, University of Heidelberg, Germany

html generated using doxygen and Python
vigra 1.11.1 (Fri May 19 2017)