ITK/Examples/Broken/Images/GradientImageFilter

GradientImageFilter.cxx

<source lang="cpp">

1. include "itkImage.h"
2. include "itkCovariantVector.h"
3. include "itkImageFileReader.h"
4. include "itkImageFileWriter.h"
5. include "itkGradientImageFilter.h"

1. include <itkImageToVTKImageFilter.h>

1. include "vtkPointData.h"
2. include "vtkFloatArray.h"
3. include "vtkImageData.h"
4. include "vtkRenderWindowInteractor.h"
5. include "vtkRenderWindow.h"
6. include "vtkSmartPointer.h"
7. include "vtkImageActor.h"
8. include "vtkActor.h"
9. include "vtkInteractorStyleImage.h"
10. include "vtkRenderer.h"
11. include "vtkGlyph3DMapper.h"
12. include "vtkArrowSource.h"

void VectorImageToVTKImage(itk::Image<itk::CovariantVector<float, 2>, 2>::Pointer vectorImage, vtkImageData* VTKImage);

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];

 // Setup types
 typedef itk::Image< float,  2 >   FloatImageType;
 typedef itk::Image< unsigned char, 2 >   UnsignedCharImageType;

 // Create and setup a reader
 typedef itk::ImageFileReader< UnsignedCharImageType >  ReaderType;
 ReaderType::Pointer reader = ReaderType::New();
 reader->SetFileName( inputFilename.c_str() );
 
 // Create and setup a gradient filter
 typedef itk::GradientImageFilter<
     UnsignedCharImageType, float>  GradientFilterType;
 GradientFilterType::Pointer gradientFilter = GradientFilterType::New();
 gradientFilter->SetInput( reader->GetOutput() );
 gradientFilter->Update();

 // Visualize original image
 typedef itk::ImageToVTKImageFilter<UnsignedCharImageType> ConnectorType;
 ConnectorType::Pointer originalConnector = ConnectorType::New();
 originalConnector->SetInput(reader->GetOutput());

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

 // Visualize gradient
 vtkSmartPointer<vtkImageData> gradientImage =
   vtkSmartPointer<vtkImageData>::New();
 VectorImageToVTKImage(gradientFilter->GetOutput(), gradientImage);
 
 vtkSmartPointer<vtkArrowSource> arrowSource =
   vtkSmartPointer<vtkArrowSource>::New();
 
 vtkSmartPointer<vtkGlyph3DMapper> gradientMapper =
   vtkSmartPointer<vtkGlyph3DMapper>::New();
 gradientMapper->ScalingOn();
 gradientMapper->SetScaleFactor(.05);
 gradientMapper->SetSourceConnection(arrowSource->GetOutputPort());
 gradientMapper->SetInputConnection(gradientImage->GetProducerPort());
 gradientMapper->Update();

 vtkSmartPointer<vtkActor> gradientActor =
   vtkSmartPointer<vtkActor>::New();
 gradientActor->SetMapper(gradientMapper);

 // Visualize
 // 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);
 rightRenderer->SetBackground(1,0,0);

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

 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 VectorImageToVTKImage(itk::Image<itk::CovariantVector<float, 2>, 2>::Pointer vectorImage, vtkImageData* VTKImage) {

 itk::Image<itk::CovariantVector<float, 2>, 2>::RegionType region = vectorImage->GetLargestPossibleRegion();
 itk::Image<itk::CovariantVector<float, 2>, 2>::SizeType imageSize = region.GetSize();
 VTKImage->SetExtent(0, imageSize[0] -1, 0, imageSize[1] - 1, 0, 0);

 vtkSmartPointer<vtkFloatArray> vectors =
   vtkSmartPointer<vtkFloatArray>::New();
 vectors->SetNumberOfComponents(3);
 vectors->SetNumberOfTuples(imageSize[0] * imageSize[1]);
 vectors->SetName("GradientVectors");

 int counter = 0;
 for(unsigned int j = 0; j < imageSize[1]; j++)
   {
   for(unsigned int i = 0; i < imageSize[0]; i++)
     {
     itk::Image<itk::CovariantVector<float, 2>, 2>::IndexType index;
     index[0] = i;
     index[1] = j;

     itk::Image<itk::CovariantVector<float, 2>, 2>::PixelType pixel = vectorImage->GetPixel(index);
   
     float v[2];
     v[0] = pixel[0];
     v[1] = pixel[1];
     v[2] = 0;
     vectors->InsertTupleValue(counter, v);
     counter++;
     }
   }
 //std::cout << region << std::endl;
 
 VTKImage->GetPointData()->SetVectors(vectors);

} </source>

CMakeLists.txt

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

PROJECT(GradientImageFilter)

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(GradientImageFilter GradientImageFilter.cxx) TARGET_LINK_LIBRARIES(GradientImageFilter vtkHybrid ITKBasicFilters ITKIO ITKCommon)

</source>