From 1ff964a17b02bf4fcddd8c03f6b759dafb9a4578 Mon Sep 17 00:00:00 2001
From: Leonardo Florez-Valencia <florez-l@javeriana.edu.co>
Date: Thu, 12 Mar 2015 18:52:49 -0500
Subject: [PATCH] Second order neighbor added

---
 .../example_ImageAlgorithmDijkstra_01.cxx     | 66 ++++++++++++++++---
 1 file changed, 58 insertions(+), 8 deletions(-)

diff --git a/appli/examples/example_ImageAlgorithmDijkstra_01.cxx b/appli/examples/example_ImageAlgorithmDijkstra_01.cxx
index b2614ed..6bcf5b3 100644
--- a/appli/examples/example_ImageAlgorithmDijkstra_01.cxx
+++ b/appli/examples/example_ImageAlgorithmDijkstra_01.cxx
@@ -1,3 +1,4 @@
+#include <cmath>
 #include <iostream>
 #include <limits>
 #include <string>
@@ -5,6 +6,10 @@
 #include <itkImage.h>
 #include <itkImageFileReader.h>
 #include <itkImageToVTKImageFilter.h>
+#include <itkMinimumMaximumImageCalculator.h>
+#include <itkInvertIntensityImageFilter.h>
+#include <itkDanielssonDistanceMapImageFilter.h>
+#include <itkUnaryFunctorImageFilter.h>
 
 #include <vtkImageActor.h>
 #include <vtkInteractorStyleImage.h>
@@ -25,30 +30,51 @@ const unsigned int Dim = 2;
 typedef unsigned char TPixel;
 typedef double TScalar;
 typedef itk::Image< TPixel, Dim >  TImage;
+typedef itk::Image< TScalar, Dim >  TScalarImage;
 typedef itk::ImageToVTKImageFilter< TImage > TVTKImage;
 
 typedef itk::ImageFileReader< TImage > TImageReader;
-typedef fpa::Image::Dijkstra< TImage, TScalar > TFrontAlgorithm;
+typedef fpa::Image::Dijkstra< TScalarImage, TScalar > TFrontAlgorithm;
 
 typedef
 fpa::VTK::Image2DObserver< TFrontAlgorithm, vtkRenderWindow >
 TObserver;
 
+// -------------------------------------------------------------------------
+class InvertPixelFunctor
+{
+public:
+  InvertPixelFunctor( )
+    { }
+  virtual ~InvertPixelFunctor( )
+    { }
+  bool operator!=( const InvertPixelFunctor& other ) const
+    { return( false ); }
+  bool operator==( const InvertPixelFunctor& other ) const
+    { return( !( *this != other ) ); }
+  inline TScalar operator()( const TScalar& A ) const
+    {
+      return( TScalar( 1 ) / std::pow( TScalar( 1 ) + A, TScalar( 4 ) ) );
+    }
+};
+
 // -------------------------------------------------------------------------
 int main( int argc, char* argv[] )
 {
-  if( argc < 2 )
+  if( argc < 3 )
   {
     std::cerr
       << "Usage: " << argv[ 0 ]
-      << " input_image [stop_at_one_front]" << std::endl;
+      << " input_image neighborhood_order [stop_at_one_front]"
+      << std::endl;
     return( 1 );
 
   } // fi
   std::string input_image_fn = argv[ 1 ];
+  unsigned int neighborhood_order = std::atoi( argv[ 2 ] );
   bool stop_at_one_front = false;
-  if( 2 < argc )
-    stop_at_one_front = ( std::atoi( argv[ 2 ] ) == 1 );
+  if( 3 < argc )
+    stop_at_one_front = ( std::atoi( argv[ 3 ] ) == 1 );
 
   // Read image
   TImageReader::Pointer input_image_reader = TImageReader::New( );
@@ -111,9 +137,33 @@ int main( int argc, char* argv[] )
   widget->On( );
   interactor->Start( );
 
+  // Compute cost map
+  typedef itk::MinimumMaximumImageCalculator< TImage > TMinMax;
+  typedef itk::InvertIntensityImageFilter< TImage > TInvert;
+  typedef itk::DanielssonDistanceMapImageFilter< TImage, TScalarImage > TDanielsson;
+  typedef itk::UnaryFunctorImageFilter< TScalarImage, TScalarImage, InvertPixelFunctor > TInvertFunctor;
+
+  TMinMax::Pointer input_image_min_max = TMinMax::New( );
+  input_image_min_max->SetImage( input_image );
+  input_image_min_max->Compute( );
+
+  TInvert::Pointer invert = TInvert::New( );
+  invert->SetInput( input_image );
+  invert->SetMaximum( input_image_min_max->GetMaximum( ) );
+
+  TDanielsson::Pointer danielsson = TDanielsson::New( );
+  danielsson->SetInput( invert->GetOutput( ) );
+  danielsson->InputIsBinaryOn( );
+  danielsson->SquaredDistanceOff( );
+  danielsson->UseImageSpacingOn( );
+
+  TInvertFunctor::Pointer invert_pixels = TInvertFunctor::New( );
+  invert_pixels->SetInput( danielsson->GetOutput( ) );
+  invert_pixels->Update( );
+
   // Configure observer
   TObserver::Pointer obs = TObserver::New( );
-  obs->SetImage( input_image, window );
+  obs->SetImage( invert_pixels->GetOutput( ), window );
 
   // Configure algorithm
   TFrontAlgorithm::Pointer algorithm = TFrontAlgorithm::New( );
@@ -137,8 +187,8 @@ int main( int argc, char* argv[] )
   } // rof
   algorithm->AddObserver( itk::AnyEvent( ), obs );
   algorithm->ThrowEventsOn( );
-  algorithm->SetInput( input_image );
-  algorithm->SetNeighborhoodOrder( 1 );
+  algorithm->SetInput( invert_pixels->GetOutput( ) );
+  algorithm->SetNeighborhoodOrder( neighborhood_order );
   algorithm->SetStopAtOneFront( stop_at_one_front );
   algorithm->Update( );
 
-- 
2.47.1