SphinxExamples/src/Core/Common/AddNoiseToBinaryImage/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 "itkImage.h"
#include "itkImageFileReader.h"
#include "itkImageRandomNonRepeatingIteratorWithIndex.h"
#include "itkImageFileWriter.h"
#include "itkMersenneTwisterRandomVariateGenerator.h"
 
int
main(int argc, char * argv[])
{
  if (argc < 3)
  {
    std::cerr << "Usage: " << argv[0] << " inputFile outputFile [percent]" << std::endl;
    return EXIT_FAILURE;
  }
  double percent = .1;
  if (argc > 3)
  {
    percent = std::stod(argv[3]);
    if (percent >= 1.0)
    {
      percent /= 100.0;
    }
  }
  using ImageType = itk::Image<unsigned char, 2>;
  using IteratorType = itk::ImageRandomNonRepeatingIteratorWithIndex<ImageType>;
 
  const auto input = itk::ReadImage<ImageType>(argv[1]);
 
  // At x% of the pixels, add a uniform random value between 0 and 255
  IteratorType it(input, input->GetLargestPossibleRegion());
  it.SetNumberOfSamples(input->GetLargestPossibleRegion().GetNumberOfPixels() * percent);
  std::cout << "Number of random samples: " << it.GetNumberOfSamples() << std::endl;
  using GeneratorType = itk::Statistics::MersenneTwisterRandomVariateGenerator;
  auto random = GeneratorType::New();
 
  it.GoToBegin();
  while (!it.IsAtEnd())
  {
    it.Set(random->GetUniformVariate(0, 255));
    ++it;
  }
 
  itk::WriteImage(input, argv[2]);
 
  return EXIT_SUCCESS;
}