ITK/Examples/Developer/ImageFilter

This example demonstrates the creation of a filter which produces the output image which is equal to the input image except its pixel on the main diagonal are turned to white.

ImageFilterExample.cxx

<source lang="cpp">

1. include "itkImage.h"
2. include "itkImageFileReader.h"
3. include "itkImageFileWriter.h"

1. include "ImageFilter.h"

int main(int, char*[]) {

 // Setup types
 typedef itk::Image<unsigned char, 2>   ImageType;
 typedef itk::ImageFilter<ImageType>  FilterType;

 typedef itk::ImageFileReader<ImageType> ReaderType;
 ReaderType::Pointer reader = ReaderType::New();
 reader->SetFileName("Test.jpg");
 reader->Update();
 
 // Create and the filter
 FilterType::Pointer filter = FilterType::New();
 filter->SetInput(reader->GetOutput());
 filter->Update();

 typedef  itk::ImageFileWriter< ImageType  > WriterType;
 WriterType::Pointer writer = WriterType::New();
 writer->SetFileName("TestOutput.jpg");
 writer->SetInput(filter->GetOutput());
 writer->Update();

 return EXIT_SUCCESS;

} </source>

ImageFilter.h

<source lang="cpp">

1. ifndef __itkImageFilter_h
2. define __itkImageFilter_h

1. include "itkImageToImageFilter.h"

namespace itk { template< class TImage> class ImageFilter:public ImageToImageFilter< TImage, TImage > { public:

 /** Standard class typedefs. */
 typedef ImageFilter             Self;
 typedef ImageToImageFilter< TImage, TImage > Superclass;
 typedef SmartPointer< Self >        Pointer;

 /** Method for creation through the object factory. */
 itkNewMacro(Self);

 /** Run-time type information (and related methods). */
 itkTypeMacro(ImageFilter, ImageToImageFilter);

protected:

 ImageFilter(){}
 ~ImageFilter(){}

 /** Does the real work. */
 virtual void GenerateData();

private:

 ImageFilter(const Self &); //purposely not implemented
 void operator=(const Self &);  //purposely not implemented

}; } //namespace ITK

1. ifndef ITK_MANUAL_INSTANTIATION
2. include "ImageFilter.txx"
3. endif

1. endif // __itkImageFilter_h

</source>

ImageFilter.txx

<source lang="cpp">

1. ifndef __itkImageFilter_txx
2. define __itkImageFilter_txx

1. include "ImageFilter.h"
2. include "itkObjectFactory.h"
3. include "itkImageRegionIterator.h"
4. include "itkImageRegionConstIterator.h"

namespace itk {

template< class TImage> void ImageFilter< TImage>

GenerateData()

{

 typename TImage::ConstPointer input = this->GetInput();
 
 typename TImage::Pointer output = this->GetOutput();
 output->SetRegions(input->GetLargestPossibleRegion());
 output->Allocate();  
 
 itk::ImageRegionIterator<TImage> outputIterator(output, output->GetLargestPossibleRegion());
 itk::ImageRegionConstIterator<TImage> inputIterator(input, input->GetLargestPossibleRegion());

 while(!outputIterator.IsAtEnd())
   {
   if(inputIterator.GetIndex()[0] == inputIterator.GetIndex()[1])
     {
     outputIterator.Set(255);
     }
   else
     {
     outputIterator.Set(inputIterator.Get());
     }

   ++inputIterator;
   ++outputIterator;
   }

}

}// end namespace

1. endif

</source>

CMakeLists.txt

<source lang="cmake"> cmake_minimum_required(VERSION 2.6)

PROJECT(ImageFilter)

FIND_PACKAGE(ITK REQUIRED) INCLUDE(${ITK_USE_FILE})

ADD_EXECUTABLE(ImageFilter ImageFilterExample.cxx) TARGET_LINK_LIBRARIES(ImageFilter ITKBasicFilters ITKIO ITKCommon)

</source>