itkSymmetricEigenAnalysisImageFilter.h

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/*=========================================================================

  Program:   Insight Segmentation & Registration Toolkit
  Module:    $RCSfile: itkSymmetricEigenAnalysisImageFilter.h,v $
  Language:  C++
  Date:      $Date: 2009-04-01 14:36:36 $
  Version:   $Revision: 1.12 $

  Copyright (c) Insight Software Consortium. All rights reserved.
  See ITKCopyright.txt or http://www.itk.org/HTML/Copyright.htm for details.

     This software is distributed WITHOUT ANY WARRANTY; without even 
     the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR 
     PURPOSE.  See the above copyright notices for more information.

=========================================================================*/
#ifndef __itkSymmetricEigenAnalysisImageFilter_h
#define __itkSymmetricEigenAnalysisImageFilter_h

#include "itkUnaryFunctorImageFilter.h"
#include "itkSymmetricEigenAnalysis.h"


namespace itk
{

// This functor class invokes the computation of Eigen Analysis for
// every pixel. The input pixel type must provide the API for the [][]
// operator, while the output pixel type must provide the API for the
// [] operator. Input pixel matrices should be symmetric.
// 
// The default operation is to order eigen values in ascending order.
// You may also use OrderEigenValuesBy( ) to order eigen values by
// magnitude as is common with use of tensors in vessel extraction.
namespace Functor {  
 
template< typename TInput, typename TOutput >
class SymmetricEigenAnalysisFunction
{
public:
  typedef typename TInput::RealValueType  RealValueType;
  SymmetricEigenAnalysisFunction() {}
  ~SymmetricEigenAnalysisFunction() {}
  typedef SymmetricEigenAnalysis< TInput, TOutput > CalculatorType;
  bool operator!=( const SymmetricEigenAnalysisFunction & ) const
    {
    return false;
    }
  bool operator==( const SymmetricEigenAnalysisFunction & other ) const
    {
    return !(*this != other);
    }

  inline TOutput operator()( const TInput & x ) const
    {
    TOutput eigenValues;
    m_Calculator.ComputeEigenValues( x, eigenValues );
    return eigenValues;
    }

  void SetDimension( unsigned int n )
    {
    m_Calculator.SetDimension(n);
    }

  typedef enum {
    OrderByValue=1,
    OrderByMagnitude,
    DoNotOrder
  } EigenValueOrderType;

  void OrderEigenValuesBy( EigenValueOrderType order )
    {
    if( order == OrderByMagnitude )
      {
      m_Calculator.SetOrderEigenMagnitudes( true );
      }
    else if( order == DoNotOrder )
      {
      m_Calculator.SetOrderEigenValues( false );
      }
    }

private:
  CalculatorType m_Calculator;
}; 

}  // end namespace functor


template <typename  TInputImage, typename  TOutputImage=TInputImage>
class ITK_EXPORT SymmetricEigenAnalysisImageFilter :
    public
UnaryFunctorImageFilter<TInputImage,TOutputImage, 
                        Functor::SymmetricEigenAnalysisFunction< 
                                        typename TInputImage::PixelType,
                                        typename TOutputImage::PixelType > >
{
public:
  typedef SymmetricEigenAnalysisImageFilter  Self;
  typedef UnaryFunctorImageFilter<
    TInputImage,TOutputImage, 
    Functor::SymmetricEigenAnalysisFunction< 
      typename TInputImage::PixelType,
      typename TOutputImage::PixelType > >   Superclass;
  typedef SmartPointer<Self>                 Pointer;
  typedef SmartPointer<const Self>           ConstPointer;

  typedef typename Superclass::OutputImageType    OutputImageType;
  typedef typename TOutputImage::PixelType        OutputPixelType;
  typedef typename TInputImage::PixelType         InputPixelType;
  typedef typename InputPixelType::ValueType      InputValueType;
  typedef typename Superclass::FunctorType        FunctorType; 

  typedef typename FunctorType::EigenValueOrderType         EigenValueOrderType;

  void OrderEigenValuesBy( EigenValueOrderType order )
    {
    this->GetFunctor().OrderEigenValuesBy( order );
    }

  itkTypeMacro( SymmetricEigenAnalysisImageFilter, UnaryFunctorImageFilter );

  itkNewMacro(Self);

  void PrintSelf(std::ostream& os, Indent indent) const
    { this->Superclass::PrintSelf( os, indent ); }

  void SetDimension( unsigned int p )
    {
    this->GetFunctor().SetDimension(p);
    }

#ifdef ITK_USE_CONCEPT_CHECKING

  itkConceptMacro(InputHasNumericTraitsCheck,
                  (Concept::HasNumericTraits<InputValueType>));

#endif

protected:
  SymmetricEigenAnalysisImageFilter() {};
  virtual ~SymmetricEigenAnalysisImageFilter() {};

private:
  SymmetricEigenAnalysisImageFilter(const Self&); //purposely not implemented
  void operator=(const Self&); //purposely not implemented

};


  
} // end namespace itk
  
#endif