ITK/Examples/ImageProcessing/ConvolutionImageFilter

ConvolutionImageFilter.cxx

<source lang="cpp">

1. include "itkImage.h"
2. include "itkImageFileReader.h"
3. include "itkImageFileWriter.h"
4. include "itkRescaleIntensityImageFilter.h"
5. include "itkConvolutionImageFilter.h"
6. include "itkImageRegionIterator.h"

1. include <itkImageToVTKImageFilter.h>

1. include "vtkImageViewer.h"
2. include "vtkRenderWindowInteractor.h"
3. include "vtkSmartPointer.h"
4. include "vtkImageActor.h"
5. include "vtkInteractorStyleImage.h"
6. include "vtkRenderer.h"

typedef itk::Image<unsigned char, 2> ImageType;

void CreateKernel(ImageType::Pointer kernel);

int main(int argc, char * argv[]) {

 // Verify command line arguments
 if( argc < 2 )
   {

std::cerr << "Usage: " << std::endl; std::cerr << argv[0] << "inputImageFile" << std::endl; return EXIT_FAILURE;

   }

 // Parse command line arguments
 std::string inputFilename = argv[1];

 ImageType::Pointer kernel = ImageType::New();
 CreateKernel(kernel);
 
 typedef itk::ImageFileReader<ImageType>  readerType;

 typedef itk::ConvolutionImageFilter<ImageType> FilterType;

 // Create and setup a reader
 readerType::Pointer reader = readerType::New();
 reader->SetFileName( inputFilename.c_str() );

 // Convolve image with kernel.
 FilterType::Pointer convolutionFilter = FilterType::New();
 convolutionFilter->SetInput(reader->GetOutput());
 convolutionFilter->SetImageKernelInput(kernel);
 convolutionFilter->Update();

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

 // To visualize the derivative, we must rescale the values
 // to a reasonable range
 typedef itk::RescaleIntensityImageFilter<

ImageType, ImageType > rescaleFilterType;

 rescaleFilterType::Pointer rescaler = rescaleFilterType::New();
 rescaler->SetOutputMinimum(0);
 rescaler->SetOutputMaximum(255);
 rescaler->SetInput( convolutionFilter->GetOutput() );
 rescaler->Update();

 typedef itk::ImageToVTKImageFilter<ImageType> ConnectorType;
 ConnectorType::Pointer originalConnector = ConnectorType::New();
 originalConnector->SetInput(reader->GetOutput());

 vtkSmartPointer<vtkImageActor> originalActor =
   vtkSmartPointer<vtkImageActor>::New();
 originalActor->SetInput(originalConnector->GetOutput());

 typedef itk::ImageToVTKImageFilter<ImageType> ConnectorType;
 ConnectorType::Pointer convolvedConnector = ConnectorType::New();
 convolvedConnector->SetInput(rescaler->GetOutput());

 vtkSmartPointer<vtkImageActor> convolvedActor =
   vtkSmartPointer<vtkImageActor>::New();
 convolvedActor->SetInput(convolvedConnector->GetOutput());

 // Define viewport ranges
 // (xmin, ymin, xmax, ymax)
 double leftViewport[4] = {0.0, 0.0, 0.5, 1.0};
 double rightViewport[4] = {0.5, 0.0, 1.0, 1.0};

 // Setup both renderers
 vtkSmartPointer<vtkRenderWindow> renderWindow =
   vtkSmartPointer<vtkRenderWindow>::New();
 renderWindow->SetSize(600,300);

 vtkSmartPointer<vtkRenderer> leftRenderer =
   vtkSmartPointer<vtkRenderer>::New();
 renderWindow->AddRenderer(leftRenderer);
 leftRenderer->SetViewport(leftViewport);

 vtkSmartPointer<vtkRenderer> rightRenderer =
   vtkSmartPointer<vtkRenderer>::New();
 renderWindow->AddRenderer(rightRenderer);
 rightRenderer->SetViewport(rightViewport);

 leftRenderer->AddActor(originalActor);
 rightRenderer->AddActor(convolvedActor);

 vtkSmartPointer<vtkRenderWindowInteractor> renderWindowInteractor =
   vtkSmartPointer<vtkRenderWindowInteractor>::New();
 vtkSmartPointer<vtkInteractorStyleImage> style =
   vtkSmartPointer<vtkInteractorStyleImage>::New();

 renderWindowInteractor->SetInteractorStyle(style);

 renderWindowInteractor->SetRenderWindow(renderWindow);
 renderWindowInteractor->Initialize();

 renderWindowInteractor->Start();

 return EXIT_SUCCESS;

}

void CreateKernel(ImageType::Pointer kernel) {

 ImageType::IndexType start;
 start.Fill(0);

 ImageType::SizeType size;
 size.Fill(3);

 ImageType::RegionType region;
 region.SetSize(size);
 region.SetIndex(start);

 kernel->SetRegions(region);
 kernel->Allocate();
 
 itk::ImageRegionIterator<ImageType> imageIterator(kernel, region);

 while(!imageIterator.IsAtEnd())
   {
   //imageIterator.Set(255);
   imageIterator.Set(1);

   ++imageIterator;
   }

} </source>

CMakeLists.txt

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

PROJECT(ConvolutionImageFilter)

include_directories(/home/doriad/src/ITK/Wrapping/WrapITK/ExternalProjects/ItkVtkGlue/src/)

FIND_PACKAGE(VTK REQUIRED) INCLUDE(${VTK_USE_FILE})

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

ADD_EXECUTABLE(ConvolutionImageFilter ConvolutionImageFilter.cxx) TARGET_LINK_LIBRARIES(ConvolutionImageFilter vtkHybrid ITKBasicFilters ITKIO ITKCommon)

</source>