/*=========================================================================
 *
 *  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.
 *
 *=========================================================================*/

// This one header will include all SimpleITK filters and external
// objects.
#include <SimpleITK.h>
#include <iostream>
#include <stdlib.h>


// create convenient namespace alias
namespace sitk = itk::simple;

int
main(int argc, char * argv[])
{

  if (argc < 4)
  {
    std::cerr << "Usage: " << argv[0] << " <input> <sigma> <output>\n";
    return 1;
  }

  // Read the image file
  sitk::ImageFileReader reader;
  reader.SetFileName(std::string(argv[1]));
  sitk::Image image = reader.Execute();

  // This filters perform a gaussian blurring with sigma in physical
  // space. The output image will be of real type.
  sitk::SmoothingRecursiveGaussianImageFilter gaussian;
  gaussian.SetSigma(atof(argv[2]));
  sitk::Image blurredImage = gaussian.Execute(image);

  // Covert the real output image back to the original pixel type, to
  // make writing easier, as many file formats don't support real
  // pixels.
  sitk::CastImageFilter caster;
  caster.SetOutputPixelType(image.GetPixelID());
  sitk::Image outputImage = caster.Execute(blurredImage);

  // write the image
  sitk::ImageFileWriter writer;
  writer.SetFileName(std::string(argv[3]));
  writer.Execute(outputImage);

  return 0;
}
