[ VIGRA Homepage | Class Index | Function Index | File Index | Main Page ]

details VectorComponentValueAccessor 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 Methods

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


Detailed Description


template<class VECTORTYPE>
class vigra::VectorComponentValueAccessor< 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 value. If you want to pass/return items by reference, use VectorComponentAccessor. 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,
                             VectorComponentValueAccessor<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


VectorComponentValueAccessor int    index [inline]

 

determine the component to be accessed


Member Function Documentation


value_type operator() ITERATOR const &    i,
DIFFERENCE const &    diff
const [inline]

 

Read the data item at an offset (can be 1D or 2D or higher order difference). The type ITERATOR::index_reference::value_type is automatically converted to value_type. In case of a conversion floating point -> intergral this includes rounding and clipping.


value_type operator() ITERATOR const &    i const [inline]

 

Read the current data item. The type ITERATOR::index_reference::value_type is automatically converted to value_type. In case of a conversion floating point -> intergral this includes rounding and clipping.


void set   value,
ITERATOR const &    i,
DIFFERENCE const &    diff
const [inline]

 

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 -> intergral this includes rounding and clipping.


void set   value,
ITERATOR const &    i
const [inline]

 

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 -> intergral this includes rounding and clipping.


void setIndex int    i [inline]

 

Reset the index to the given number.


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

© Ullrich Köthe (koethe@informatik.uni-hamburg.de)
Cognitive Systems Group, University of Hamburg, Germany

html generated using doxygen and Python
VIGRA 1.3.3 (18 Aug 2005)