ITK/Examples/Iterators/ConstantBoundaryCondition

#include "itkImage.h"
#include "itkImageFileReader.h"
#include "itkConstNeighborhoodIterator.h"
#include "itkConstantBoundaryCondition.h"
#include "itkImageRegionIterator.h"
 
#include <itkImageToVTKImageFilter.h>
 
#include "vtkVersion.h"
#include "vtkImageViewer.h"
#include "vtkImageMapper3D.h"
#include "vtkRenderWindowInteractor.h"
#include "vtkSmartPointer.h"
#include "vtkImageActor.h"
#include "vtkInteractorStyleImage.h"
#include "vtkRenderer.h"
 
typedef itk::Image<unsigned char, 2>  ImageType;
static void CreateImage(ImageType::Pointer image);
 
int main(int, char*[])
{
  ImageType::Pointer image = ImageType::New();
  CreateImage(image);
 
  ImageType::SizeType regionSize;
  regionSize[0] = 50;
  regionSize[1] = 1;
 
  ImageType::IndexType regionIndex;
  regionIndex[0] = 0;
  regionIndex[1] = 0;
 
  ImageType::RegionType region;
  region.SetSize(regionSize);
  region.SetIndex(regionIndex);
 
  ImageType::SizeType radius;
  radius[0] = 1;
  radius[1] = 1;
 
  typedef itk::ConstantBoundaryCondition<ImageType>  BoundaryConditionType;
  itk::ConstNeighborhoodIterator<ImageType, BoundaryConditionType> iterator(radius, image,region);
 
  while(!iterator.IsAtEnd())
    {
    for(unsigned int i = 0; i < 9; i++)
      {
      ImageType::IndexType index = iterator.GetIndex(i);
 
      std::cout << "Index: " << index
                << " Pixel: " << i << " = "
                << (int)iterator.GetPixel(i) << std::endl;
      }
    ++iterator;
    }
 
  // Visualize
  typedef itk::ImageToVTKImageFilter<ImageType> ConnectorType;
  ConnectorType::Pointer connector = ConnectorType::New();
  connector->SetInput(image);
 
  vtkSmartPointer<vtkImageActor> actor =
    vtkSmartPointer<vtkImageActor>::New();
#if VTK_MAJOR_VERSION <= 5
  actor->SetInput(connector->GetOutput());
#else
  connector->Update();
  actor->GetMapper()->SetInputData(connector->GetOutput());
#endif
 
  vtkSmartPointer<vtkRenderWindow> renderWindow =
    vtkSmartPointer<vtkRenderWindow>::New();
 
  vtkSmartPointer<vtkRenderWindowInteractor> interactor =
    vtkSmartPointer<vtkRenderWindowInteractor>::New();
  interactor->SetRenderWindow(renderWindow);
 
  vtkSmartPointer<vtkRenderer> renderer =
    vtkSmartPointer<vtkRenderer>::New();
  renderWindow->AddRenderer(renderer);
 
  renderer->AddActor(actor);
  renderer->ResetCamera();
 
  renderWindow->Render();
 
  vtkSmartPointer<vtkInteractorStyleImage> style =
    vtkSmartPointer<vtkInteractorStyleImage>::New();
 
  interactor->SetInteractorStyle(style);
 
  interactor->Start();
 
  return EXIT_SUCCESS;
}
 
void CreateImage(ImageType::Pointer image)
{
  // Create an image with 2 connected components
  ImageType::RegionType region;
  ImageType::IndexType start;
  start[0] = 0;
  start[1] = 0;
 
  ImageType::SizeType size;
  unsigned int NumRows = 5;
  unsigned int NumCols = 5;
  size[0] = NumRows;
  size[1] = NumCols;
 
  region.SetSize(size);
  region.SetIndex(start);
 
  image->SetRegions(region);
  image->Allocate();
 
  itk::ImageRegionIterator<ImageType> imageIterator(image,region);
 
  // Set all pixels to white
  while(!imageIterator.IsAtEnd())
    {
    imageIterator.Set(255);
    ++imageIterator;
    }
}