#include <ctime>
#include <iostream>
#include <string>

#include <itkImage.h>
#include <itkImageFileReader.h>
#include <itkImageFileWriter.h>
#include <itkInvertIntensityImageFilter.h>
#include <itkMinimumMaximumImageCalculator.h>
#include <itkDanielssonDistanceMapImageFilter.h>

// -------------------------------------------------------------------------
const unsigned int Dim = 3;
typedef unsigned char                        TPixel;
typedef float                                TScalar;
typedef itk::Image< TPixel, Dim >            TImage;
typedef itk::Image< TScalar, Dim >           TScalarImage;
typedef itk::ImageFileReader< TImage >       TImageReader;
typedef itk::ImageFileWriter< TScalarImage > TImageWriter;

// -------------------------------------------------------------------------
int main( int argc, char* argv[] )
{
  if( argc < 3 )
  {
    std::cerr
      << "Usage: " << argv[ 0 ]
      << " input_image output_image"
      << std::endl;
    return( 1 );

  } // fi
  std::string input_image_fn = argv[ 1 ];
  std::string output_image_fn = argv[ 2 ];

  // Read image
  TImageReader::Pointer input_image_reader = TImageReader::New( );
  input_image_reader->SetFileName( input_image_fn );
  try
  {
    input_image_reader->Update( );
  }
  catch( itk::ExceptionObject& err )
  {
    std::cerr << "Error caught: " << err << std::endl;
    return( 1 );

  } // yrt

  // Invert intensity
  typedef itk::MinimumMaximumImageCalculator< TImage > TMinMax;
  TMinMax::Pointer minmax = TMinMax::New( );
  minmax->SetImage( input_image_reader->GetOutput( ) );
  minmax->Compute( );

  typedef itk::InvertIntensityImageFilter< TImage > TInvert;
  TInvert::Pointer invert = TInvert::New( );
  invert->SetInput( input_image_reader->GetOutput( ) );
  invert->SetMaximum( minmax->GetMaximum( ) );

  typedef itk::DanielssonDistanceMapImageFilter< TImage, TScalarImage > TDistance;
  TDistance::Pointer distance = TDistance::New( );
  distance->SetInput( invert->GetOutput( ) );
  distance->InputIsBinaryOn( );
  distance->SquaredDistanceOn( );
  std::clock_t start = std::clock( );
  distance->Update( );
  std::clock_t end = std::clock( );
  double seconds = double( end - start ) / double( CLOCKS_PER_SEC );
  std::cout << "Distance map time = " << seconds << std::endl;

  TImageWriter::Pointer writer = TImageWriter::New( );
  writer->SetInput( distance->GetOutput( ) );
  writer->SetFileName( output_image_fn );
  writer->Update( );

  return( 0 );
}

// eof - $RCSfile$