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

details Algorithms to Initialize Images VIGRA


Functions

template<...> void initImage (ImageIterator upperleft, ImageIterator lowerright, Accessor a, VALUETYPE v)
 Write a value to every pixel in an image or rectangular ROI.

template<...> void initImageWithFunctor (ImageIterator upperleft, ImageIterator lowerright, Accessor a, FUNCTOR f)
 Write the result of a functor call to every pixel in an image or rectangular ROI.

template<...> void initImageIf (ImageIterator upperleft, ImageIterator lowerright, Accessor a, MaskImageIterator mask_upperleft, MaskAccessor ma, VALUETYPE v)
 Write value to pixel in the image if mask is true.

template<...> void initImageBorder (ImageIterator upperleft, ImageIterator lowerright, Accessor a, int border_width, VALUETYPE v)
 Write value to the specified border pixels in the image.



Detailed Description


Init images or image borders


Function Documentation


  void initImage (...)
 
 

Write a value to every pixel in an image or rectangular ROI.

This function can be used to init the image. It uses an accessor to access the pixel data.

Declarations:

pass arguments explicitly:

    namespace vigra {
        template <class ImageIterator, class Accessor, class VALUETYPE>
        void
        initImage(ImageIterator upperleft, ImageIterator lowerright, 
              Accessor a, VALUETYPE v)
    }

use argument objects in conjunction with Argument Object Factories:

    namespace vigra {
        template <class ImageIterator, class Accessor, class VALUETYPE>
        void
        initImage(triple<ImageIterator, ImageIterator, Accessor> img, VALUETYPE v)
    }

Usage:

#include "vigra/initimage.hxx"
Namespace: vigra

    vigra::BImage img(100, 100);
    
    // zero the image
    vigra::initImage(destImageRange(img),
                     vigra::NumericTraits<vigra::BImage::PixelType>::zero());

Required Interface:

    ImageIterator upperleft, lowerright;
    ImageIterator::row_iterator ix = upperleft.rowIterator();
    
    Accessor accessor;
    VALUETYPE v;
    
    accessor.set(v, ix); 


  void initImageBorder (...)
 
 

Write value to the specified border pixels in the image.

A pixel is initialized if its distance to the border is at most 'borderwidth'. It uses an accessor to access the pixel data.

Declarations:

pass arguments explicitly:

    namespace vigra {
        template <class ImageIterator, class Accessor, class VALUETYPE>
        void
        initImageBorder(ImageIterator upperleft, ImageIterator lowerright, 
                Accessor a,  int border_width, VALUETYPE v)
    }

use argument objects in conjunction with Argument Object Factories:

    namespace vigra {
        template <class ImageIterator, class Accessor, class VALUETYPE>
        void
        initImageBorder(triple<ImageIterator, ImageIterator, Accessor> img, 
                int border_width, VALUETYPE v)
    }

Usage:

#include "vigra/initimage.hxx"
Namespace: vigra

    vigra::BImage img(100, 100);
    
    // zero a border of 5 pixel
    vigra::initImageBorder(destImageRange(img),
                    5, vigra::NumericTraits<vigra::BImage::PixelType>::zero());

Required Interface:

see initImage()


  void initImageIf (...)
 
 

Write value to pixel in the image if mask is true.

This function can be used to init a region-of-interest of the image. It uses an accessor to access the pixel data.

Declarations:

pass arguments explicitly:

    namespace vigra {
        template <class ImageIterator, class Accessor, 
              class MaskImageIterator, class MaskAccessor,
              class VALUETYPE>
        void
        initImageIf(ImageIterator upperleft, ImageIterator lowerright, Accessor a,
              MaskImageIterator mask_upperleft, MaskAccessor ma,
              VALUETYPE v)
    }

use argument objects in conjunction with Argument Object Factories:

    namespace vigra {
        template <class ImageIterator, class Accessor, 
              class MaskImageIterator, class MaskAccessor,
              class VALUETYPE>
        void
        initImageIf(triple<ImageIterator, ImageIterator, Accessor> img, 
            pair<MaskImageIterator, MaskAccessor> mask,
            VALUETYPE v)
    }

Usage:

#include "vigra/initimage.hxx"
Namespace: vigra

    vigra::BImage img(100, 100);
    vigra::BImage mask(100, 100);
    
    // zero the ROI
    vigra::initImageIf(destImageRange(img), 
                maskImage(mask),
                vigra::NumericTraits<vigra::BImage::PixelType>::zero());

Required Interface:

    ImageIterator upperleft, lowerright;
    MaskImageIterator mask_upperleft;
    ImageIterator::row_iterator ix = upperleft.rowIterator();
    MaskImageIterator::row_iterator mx = mask_upperleft.rowIterator();
    
    Accessor accessor;
    MaskAccessor mask_accessor;
    VALUETYPE v;
    
    if(mask_accessor(mx)) accessor.set(v, ix); 


  void initImageWithFunctor (...)
 
 

Write the result of a functor call to every pixel in an image or rectangular ROI.

This function can be used to init the image by calling the given functor for each pixel. It uses an accessor to access the pixel data.

Declarations:

pass arguments explicitly:

    namespace vigra {
        template <class ImageIterator, class Accessor, class FUNCTOR>
        void
        initImageWithFunctor(ImageIterator upperleft, ImageIterator lowerright, 
                  Accessor a,  FUNCTOR f);
    }

use argument objects in conjunction with Argument Object Factories:

    namespace vigra {
        template <class ImageIterator, class Accessor, class FUNCTOR>
        void
        initImageWithFunctor(triple<ImageIterator, ImageIterator, Accessor> img, FUNCTOR f);
    }

Usage:

#include "vigra/initimage.hxx"
Namespace: vigra

    struct Counter {
        Counter() : count(0) {}
        
        int operator()() const { return count++; }
    
        mutable int count;
    };
    
    vigra::IImage img(100, 100);
    
    // write the current count in every pixel
    vigra::initImageWithFunctor(destImageRange(img), Counter());

Required Interface:

    ImageIterator upperleft, lowerright;
    ImageIterator::row_iterator ix = upperleft.rowIterator();
    
    Accessor accessor;
    Functor f;
    
    accessor.set(f(), ix); 

© 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)