Smooth Image With Discrete Gaussian Filter

Synopsis

Smooth an image with a discrete Gaussian filter.

Results

../../../../_images/Yinyang28.png

Input image.

Code

C++

#include "itkImage.h"
#include "itkImageFileReader.h"
#include "itkDiscreteGaussianImageFilter.h"

#ifdef ENABLE_QUICKVIEW
#  include "QuickView.h"
#endif

int
main(int argc, char * argv[])
{
  // Verify command line arguments
  if (argc < 2)
  {
    std::cerr << "Usage: " << std::endl;
    std::cerr << argv[0] << " inputImageFile [variance]" << std::endl;
    return EXIT_FAILURE;
  }

  // Parse command line argumentsa
  std::string inputFilename = argv[1];

  double variance = 4.0;
  if (argc > 2)
  {
    variance = std::stod(argv[2]);
  }

  // Setup types
  using UnsignedCharImageType = itk::Image<unsigned char, 2>;
  using FloatImageType = itk::Image<float, 2>;

  using readerType = itk::ImageFileReader<UnsignedCharImageType>;

  using filterType = itk::DiscreteGaussianImageFilter<UnsignedCharImageType, FloatImageType>;

  // Create and setup a reader
  readerType::Pointer reader = readerType::New();
  reader->SetFileName(inputFilename.c_str());

  // Create and setup a Gaussian filter
  filterType::Pointer gaussianFilter = filterType::New();
  gaussianFilter->SetInput(reader->GetOutput());
  gaussianFilter->SetVariance(variance);

#ifdef ENABLE_QUICKVIEW
  QuickView viewer;
  viewer.AddImage<UnsignedCharImageType>(reader->GetOutput());
  viewer.AddImage<FloatImageType>(gaussianFilter->GetOutput());
  viewer.Visualize();
#endif

  return EXIT_SUCCESS;
}

Classes demonstrated