SphinxExamples/src/Core/SpatialObjects/ConvertSpatialObjectToImage/Code.cxx

/*=========================================================================
 *
 *  Copyright NumFOCUS
 *
 *  Licensed under the Apache License, Version 2.0 (the "License");
 *  you may not use this file except in compliance with the License.
 *  You may obtain a copy of the License at
 *
 *         https://www.apache.org/licenses/LICENSE-2.0.txt
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS,
 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 *
 *=========================================================================*/
#include "itkSpatialObjectToImageFilter.h"
#include "itkEllipseSpatialObject.h"
#include "itkImageFileWriter.h"
 
int
main(int argc, char * argv[])
{
  if (argc != 2)
  {
    std::cerr << "Usage: " << argv[0] << " outputimagefile " << std::endl;
    return EXIT_FAILURE;
  }
 
  using PixelType = unsigned char;
  constexpr unsigned int Dimension = 2;
 
  using ImageType = itk::Image<PixelType, Dimension>;
 
  using EllipseType = itk::EllipseSpatialObject<Dimension>;
 
  using SpatialObjectToImageFilterType = itk::SpatialObjectToImageFilter<EllipseType, ImageType>;
 
  auto imageFilter = SpatialObjectToImageFilterType::New();
 
  //  The SpatialObjectToImageFilter requires that the user defines the grid
  //  parameters of the output image. This includes the number of pixels along
  //  each dimension, the pixel spacing, image direction and
 
  ImageType::SizeType size;
  size[0] = 50;
  size[1] = 50;
 
  imageFilter->SetSize(size);
 
  ImageType::SpacingType spacing;
  spacing[0] = 100.0 / size[0];
  spacing[1] = 100.0 / size[1];
 
  imageFilter->SetSpacing(spacing);
 
  auto                   ellipse = EllipseType::New();
  EllipseType::ArrayType radiusArray;
  radiusArray[0] = 10;
  radiusArray[1] = 20;
  // ellipse->SetRadiusInObjectSpace(  size[0] * 0.2 * spacing[0] );
  ellipse->SetRadiusInObjectSpace(radiusArray);
 
  // Position the ellipse
 
  using TransformType = EllipseType::TransformType;
 
  auto transform = TransformType::New();
 
  transform->SetIdentity();
 
  TransformType::OutputVectorType translation;
  translation[0] = size[0] * spacing[0] / 2.0;
  translation[1] = size[1] * spacing[1] / 4.0;
  transform->Translate(translation, false);
 
  ellipse->SetObjectToParentTransform(transform);
 
  imageFilter->SetInput(ellipse);
 
  ellipse->SetDefaultInsideValue(255);
 
  ellipse->SetDefaultOutsideValue(0);
 
  imageFilter->SetUseObjectValue(true);
 
  imageFilter->SetOutsideValue(0);
 
  try
  {
    imageFilter->Update();
    itk::WriteImage(imageFilter->GetOutput(), argv[1], true); // compress
  }
  catch (const itk::ExceptionObject & excp)
  {
    std::cerr << excp << std::endl;
    return EXIT_FAILURE;
  }
 
  return EXIT_SUCCESS;
}