ITK/Examples/ImageProcessing/AddConstantToImageFilter

#include "itkImage.h"
#include "itkAddImageFilter.h"
#include "itkImageFileWriter.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);
 
  typedef itk::AddImageFilter <ImageType, ImageType, ImageType> AddImageFilterType;
  AddImageFilterType::Pointer addImageFilter = AddImageFilterType::New();
  addImageFilter->SetInput(image);
  addImageFilter->SetConstant2(2);
  addImageFilter->Update();
 
  typedef  itk::ImageFileWriter< ImageType  > WriterType;
  WriterType::Pointer writer = WriterType::New();
  writer->SetFileName("output.png");
  writer->SetInput(addImageFilter->GetOutput());
  writer->Update();
 
  return EXIT_SUCCESS;
}
 
void CreateImage(ImageType::Pointer image)
{
  ImageType::IndexType start;
  start.Fill(0);
 
  ImageType::SizeType size;
  size.Fill(100);
 
  ImageType::RegionType region;
  region.SetSize(size);
  region.SetIndex(start);
 
  image->SetRegions(region);
  image->Allocate();
 
  itk::ImageRegionIterator<ImageType> imageIterator(image,region);
 
  while(!imageIterator.IsAtEnd())
    {
    if(imageIterator.GetIndex()[0] < 70)
      {
      imageIterator.Set(255);
      }
    else
      {
      imageIterator.Set(0);
      }
 
    ++imageIterator;
    }
 
}