SphinxExamples/src/Filtering/ImageFeature/DetectEdgesWithCannyFilter/Code.cxx

/*=========================================================================
 *
 *  Copyright Insight Software Consortium
 *
 *  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 "itkCannyEdgeDetectionImageFilter.h"
#include "itkRescaleIntensityImageFilter.h"

int main( int argc, char* argv[] )
{
  if( argc != 6 )
    {
    std::cerr << "Usage: "<< std::endl;
    std::cerr << argv[0];
    std::cerr << "<InputImage> <OutputImage> ";
    std::cerr << "<Variance> <LowerThreshold> <UpperThreshold>";
    std::cerr << std::endl;
    return EXIT_FAILURE;
    }

  constexpr unsigned int Dimension = 2;
  using InputPixelType = float;
  using OutputPixelType = unsigned char;

  const char * inputImage = argv[1];
  const char * outputImage = argv[2];
  const InputPixelType variance = atof( argv[3] );
  const InputPixelType lowerThreshold = atof( argv[4] );
  const InputPixelType upperThreshold = atof( argv[5] );

  using InputImageType = itk::Image<InputPixelType, Dimension>;
  using OutputImageType = itk::Image<OutputPixelType, Dimension>;

  using ReaderType = itk::ImageFileReader< InputImageType >;
  ReaderType::Pointer reader = ReaderType::New();
  reader->SetFileName( inputImage );

  using FilterType = itk::CannyEdgeDetectionImageFilter< InputImageType, InputImageType >;
  FilterType::Pointer filter = FilterType::New();
  filter->SetInput( reader->GetOutput() );
  filter->SetVariance( variance );
  filter->SetLowerThreshold( lowerThreshold );
  filter->SetUpperThreshold( upperThreshold );

  using RescaleType = itk::RescaleIntensityImageFilter< InputImageType, OutputImageType >;
  RescaleType::Pointer rescaler = RescaleType::New();
  rescaler->SetInput( filter->GetOutput() );
  rescaler->SetOutputMinimum( 0 );
  rescaler->SetOutputMaximum( 255 );

  using WriterType = itk::ImageFileWriter< OutputImageType >;
  WriterType::Pointer writer = WriterType::New();
  writer->SetFileName( outputImage );
  writer->SetInput( rescaler->GetOutput() );

  try
    {
    writer->Update();
    }
  catch( itk::ExceptionObject & e )
    {
    std::cerr << "Error: " << e << std::endl;
    return EXIT_FAILURE;
    }

  return EXIT_SUCCESS;
}