ITK  5.0.0
Insight Segmentation and Registration Toolkit
WikiExamples/Registration/DeformationFieldTransform.cxx
#include "itkImage.h"
#include "itkVector.h"
#if ITK_VERSION_MAJOR < 4
#include "itkDeformationFieldTransform.h"
#include "itkDeformationFieldSource.h"
#else
#endif
constexpr unsigned int Dimension = 2;
using PixelType = unsigned char;
static void CreateFixedImage(ImageType::Pointer image);
static void CreateMovingImage(ImageType::Pointer image);
int main(int argc, char * argv[])
{
#if ITK_VERSION_MAJOR < 4
using VectorComponentType = float;
#else
using VectorComponentType = double;
#endif
using DeformationFieldType = itk::Image< VectorType, Dimension >;
ImageType::Pointer fixedImage = ImageType::New();
CreateFixedImage(fixedImage);
ImageType::Pointer movingImage = ImageType::New();
CreateMovingImage(movingImage);
#if ITK_VERSION_MAJOR < 4
using DeformationFieldSourceType = itk::DeformationFieldSource<DeformationFieldType>;
#else
#endif
DeformationFieldSourceType::Pointer deformationFieldSource = DeformationFieldSourceType::New();
deformationFieldSource->SetOutputSpacing( fixedImage->GetSpacing() );
deformationFieldSource->SetOutputOrigin( fixedImage->GetOrigin() );
deformationFieldSource->SetOutputRegion( fixedImage->GetLargestPossibleRegion() );
deformationFieldSource->SetOutputDirection( fixedImage->GetDirection() );
// Create source and target landmarks.
using LandmarkContainerType = DeformationFieldSourceType::LandmarkContainer;
using LandmarkPointType = DeformationFieldSourceType::LandmarkPointType;
LandmarkContainerType::Pointer sourceLandmarks = LandmarkContainerType::New();
LandmarkContainerType::Pointer targetLandmarks = LandmarkContainerType::New();
LandmarkPointType sourcePoint;
LandmarkPointType targetPoint;
sourcePoint[0] = 40;
sourcePoint[1] = 40;
targetPoint[0] = 20;
targetPoint[1] = 20;
sourceLandmarks->InsertElement( 0, sourcePoint );
targetLandmarks->InsertElement( 0, targetPoint );
sourcePoint[0] = 40;
sourcePoint[1] = 60;
targetPoint[0] = 20;
targetPoint[1] = 80;
sourceLandmarks->InsertElement( 1, sourcePoint );
targetLandmarks->InsertElement( 1, targetPoint );
sourcePoint[0] = 60;
sourcePoint[1] = 40;
targetPoint[0] = 80;
targetPoint[1] = 20;
sourceLandmarks->InsertElement( 2, sourcePoint );
targetLandmarks->InsertElement( 2, targetPoint );
sourcePoint[0] = 60;
sourcePoint[1] = 60;
targetPoint[0] = 80;
targetPoint[1] = 80;
sourceLandmarks->InsertElement( 3, sourcePoint );
targetLandmarks->InsertElement( 3, targetPoint );
deformationFieldSource->SetSourceLandmarks( sourceLandmarks.GetPointer() );
deformationFieldSource->SetTargetLandmarks( targetLandmarks.GetPointer() );
deformationFieldSource->UpdateLargestPossibleRegion();
// Write the deformation field
{
WriterType::Pointer writer = WriterType::New();
writer->SetInput ( deformationFieldSource->GetOutput() );
writer->SetFileName( "deformation.mhd" );
writer->Update();
}
#if ITK_VERSION_MAJOR < 4
using DeformationFieldTransformType = itk::DeformationFieldTransform<VectorComponentType, 2>;
#else
using DeformationFieldTransformType = itk::DisplacementFieldTransform<VectorComponentType, 2>;
#endif
DeformationFieldTransformType::Pointer deformationFieldTransform = DeformationFieldTransformType::New();
#if ITK_VERSION_MAJOR < 4
deformationFieldTransform->SetDeformationField( deformationFieldSource->GetOutput() );
#else
deformationFieldTransform->SetDisplacementField( deformationFieldSource->GetOutput() );
#endif
ResampleFilterType::Pointer resampleFilter = ResampleFilterType::New();
resampleFilter->SetInput( movingImage );
resampleFilter->SetTransform( deformationFieldTransform );
resampleFilter->SetSize( fixedImage->GetLargestPossibleRegion().GetSize() );
resampleFilter->SetOutputOrigin( fixedImage->GetOrigin() );
resampleFilter->SetOutputSpacing( fixedImage->GetSpacing() );
resampleFilter->SetOutputDirection( fixedImage->GetDirection() );
resampleFilter->SetDefaultPixelValue( 200 );
resampleFilter->GetOutput();
// Write the output
WriterType::Pointer writer = WriterType::New();
writer->SetInput ( resampleFilter->GetOutput() );
writer->SetFileName( "output.png" );
writer->Update();
return EXIT_SUCCESS;
}
void CreateFixedImage(ImageType::Pointer image)
{
// Create a black image with a white square
start.Fill(0);
size.Fill(100);
region.SetSize(size);
region.SetIndex(start);
image->SetRegions(region);
image->Allocate();
image->FillBuffer(0);
itk::ImageRegionIterator<ImageType> imageIterator(image,region);
while(!imageIterator.IsAtEnd())
{
if(imageIterator.GetIndex()[0] > 40 && imageIterator.GetIndex()[0] < 60 &&
imageIterator.GetIndex()[1] > 40 && imageIterator.GetIndex()[1] < 60)
{
imageIterator.Set(255);
}
++imageIterator;
}
// Write the deformation field
WriterType::Pointer writer = WriterType::New();
writer->SetInput ( image );
writer->SetFileName( "fixed.png" );
writer->Update();
}
void CreateMovingImage(ImageType::Pointer image)
{
// Create a black image with a white square
start.Fill(0);
size.Fill(100);
region.SetSize(size);
region.SetIndex(start);
image->SetRegions(region);
image->Allocate();
image->FillBuffer(0);
itk::ImageRegionIterator<ImageType> imageIterator(image,region);
while(!imageIterator.IsAtEnd())
{
if(imageIterator.GetIndex()[0] > 20 && imageIterator.GetIndex()[0] < 80 &&
imageIterator.GetIndex()[1] > 20 && imageIterator.GetIndex()[1] < 80)
{
imageIterator.Set(100);
}
++imageIterator;
}
// Write the deformation field
WriterType::Pointer writer = WriterType::New();
writer->SetInput ( image );
writer->SetFileName( "moving.png" );
writer->Update();
}