DataRepresentation/Path/PolyLineParametricPath1.cxx

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 *
 *  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.
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 *         http://www.apache.org/licenses/LICENSE-2.0.txt
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// Software Guide : BeginLatex
//
// This example illustrates how to use the \doxygen{PolyLineParametricPath}.
// This class will typically be used for representing in a concise way the
// output of an image segmentation algorithm in 2D.  The
// \code{PolyLineParametricPath} however could also be used for representing
// any open or close curve in N-Dimensions as a linear piece-wise approximation.
//
//
// First, the header file of the \code{PolyLineParametricPath} class must be included.
//
// Software Guide : EndLatex


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

// Software Guide : BeginCodeSnippet
#include "itkPolyLineParametricPath.h"
// Software Guide : EndCodeSnippet

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

  if( argc < 2 )
    {
    std::cerr << "Missing arguments" << std::endl;
    std::cerr << "Usage: PolyLineParametricPath  inputImageFileName" << std::endl;
    return -1;
    }

  // Software Guide : BeginLatex
  //
  // The path is instantiated over the dimension of the image. In this case 2D. //
  // Software Guide : EndLatex

  // Software Guide : BeginCodeSnippet
  const unsigned int Dimension = 2;

  typedef itk::Image< unsigned char, Dimension > ImageType;

  typedef itk::PolyLineParametricPath< Dimension > PathType;
  // Software Guide : EndCodeSnippet


  typedef itk::ImageFileReader< ImageType >    ReaderType;

  ReaderType::Pointer   reader = ReaderType::New();

  reader->SetFileName( argv[1] );

  try
    {
    reader->Update();
    }
  catch( itk::ExceptionObject & excp )
    {
    std::cout << "Problem reading the input image " << std::endl;
    std::cout << excp << std::endl;
    return -1;
    }

  // Software Guide : BeginCodeSnippet

  ImageType::ConstPointer image = reader->GetOutput();


  PathType::Pointer path = PathType::New();


  path->Initialize();


  typedef PathType::ContinuousIndexType    ContinuousIndexType;

  ContinuousIndexType cindex;

  typedef ImageType::PointType             ImagePointType;

  ImagePointType origin = image->GetOrigin();


  ImageType::SpacingType spacing = image->GetSpacing();
  ImageType::SizeType    size    = image->GetBufferedRegion().GetSize();

  ImagePointType point;

  point[0] = origin[0] + spacing[0] * size[0];
  point[1] = origin[1] + spacing[1] * size[1];

  image->TransformPhysicalPointToContinuousIndex( origin, cindex );

  path->AddVertex( cindex );

  image->TransformPhysicalPointToContinuousIndex( point, cindex );

  path->AddVertex( cindex );



  // Software Guide : EndCodeSnippet

  return 0;
}