Examples/Filtering/ResampleImageFilter6.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
 *
 *         http://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 "itkImage.h"
#include "itkImageFileReader.h"
#include "itkImageFileWriter.h"
#include "itkResampleImageFilter.h"
#include "itkIdentityTransform.h"
#include "itkRGBPixel.h"
 
 
int
main(int argc, char * argv[])
{
  if (argc < 3)
  {
    std::cerr << "Usage: " << std::endl;
    std::cerr << argv[0] << "  inputImageFile  outputImageFile" << std::endl;
    return EXIT_FAILURE;
  }
 
  constexpr unsigned int Dimension = 2;
  using PixelComponentType = unsigned char;
  using PixelType = itk::RGBPixel<PixelComponentType>;
 
  using ImageType = itk::Image<PixelType, Dimension>;
 
 
  using ReaderType = itk::ImageFileReader<ImageType>;
  using WriterType = itk::ImageFileWriter<ImageType>;
 
  ReaderType::Pointer reader = ReaderType::New();
  WriterType::Pointer writer = WriterType::New();
 
  reader->SetFileName(argv[1]);
  writer->SetFileName(argv[2]);
 
 
  using FilterType = itk::ResampleImageFilter<ImageType, ImageType>;
 
  FilterType::Pointer filter = FilterType::New();
 
  using InterpolatorType =
    itk::LinearInterpolateImageFunction<ImageType, double>;
  InterpolatorType::Pointer interpolator = InterpolatorType::New();
 
  filter->SetInterpolator(interpolator);
 
 
  using TransformType = itk::IdentityTransform<double, Dimension>;
  TransformType::Pointer transform = TransformType::New();
 
  filter->SetTransform(transform);
 
 
  // Software Guide : BeginCodeSnippet
  PixelType defaultValue;
  defaultValue.Fill(50);
 
  filter->SetDefaultPixelValue(defaultValue);
  // Software Guide : EndCodeSnippet
 
 
  // Software Guide : BeginCodeSnippet
  ImageType::SpacingType spacing;
  spacing[0] = .5; // pixel spacing in millimeters along X
  spacing[1] = .5; // pixel spacing in millimeters along Y
 
  filter->SetOutputSpacing(spacing);
  // Software Guide : EndCodeSnippet
 
 
  // Software Guide : BeginCodeSnippet
  ImageType::PointType origin;
  origin[0] = 30.0; // X space coordinate of origin
  origin[1] = 40.0; // Y space coordinate of origin
  filter->SetOutputOrigin(origin);
  // Software Guide : EndCodeSnippet
 
 
  // Software Guide : BeginCodeSnippet
  ImageType::DirectionType direction;
  direction.SetIdentity();
  filter->SetOutputDirection(direction);
  // Software Guide : EndCodeSnippet
 
 
  ImageType::SizeType size;
 
  size[0] = 300; // number of pixels along X
  size[1] = 300; // number of pixels along Y
 
  filter->SetSize(size);
 
  filter->SetInput(reader->GetOutput());
  writer->SetInput(filter->GetOutput());
 
 
  try
  {
    writer->Update();
  }
  catch (const itk::ExceptionObject & excp)
  {
    std::cerr << "Exception thrown " << std::endl;
    std::cerr << excp << std::endl;
  }
 
  return EXIT_SUCCESS;
}