ITK  5.0.0
Insight Segmentation and Registration Toolkit
WikiExamples/Registration/WarpImageFilter.cxx
#include "itkImage.h"
#include "itkVector.h"
#if ITK_VERSION_MAJOR < 4
#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, char *[])
{
using VectorComponentType = float;
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();
}
using WarpImageFilterType = itk::WarpImageFilter< ImageType,
ImageType,
DeformationFieldType >;
WarpImageFilterType::Pointer warpImageFilter =
WarpImageFilterType::New();
InterpolatorType::Pointer interpolator =
InterpolatorType::New();
warpImageFilter->SetInterpolator( interpolator );
warpImageFilter->SetOutputSpacing( deformationFieldSource->GetOutput()->GetSpacing() );
warpImageFilter->SetOutputOrigin( deformationFieldSource->GetOutput()->GetOrigin() );
#if ITK_VERSION_MAJOR < 4
warpImageFilter->SetDeformationField( deformationFieldSource->GetOutput() );
#else
warpImageFilter->SetDisplacementField( deformationFieldSource->GetOutput() );
#endif
warpImageFilter->SetInput( movingImage );
warpImageFilter->Update();
// Write the output
WriterType::Pointer writer =
WriterType::New();
writer->SetInput ( warpImageFilter->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();
}