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

  Program:   Insight Segmentation & Registration Toolkit
  Module:    $RCSfile: itkCastImageFilter.h,v $
  Language:  C++
  Date:      $Date: 2006/03/13 15:54:34 $
  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 __itkCastImageFilter_h
#define __itkCastImageFilter_h

#include "itkUnaryFunctorImageFilter.h"

namespace itk
{
  
/** \class CastImageFilter
 *
 * \brief Casts input pixels to output pixel type.
 *
 * This filter is templated over the input image type
 * and the output image type.
 * 
 * CastImageFilter allows the input and output image to be different
 * dimensions.  This is useful if you want to cast an 2D image to
 * 3D image.  The resulting 3D image will have a single slice. If you
 * attempt to cast an image to a lower dimension, the first "slice"
 * (or line or volume) will be extracted.  If you want to convert
 * an image to a lower dimension and specify the subspace (i.e. which
 * slice of a volume, etc.) then you should use ExtractImageFilter.
 *
 * \ingroup IntensityImageFilters  Multithreaded
 * \sa UnaryFunctorImageFilter
 * \sa ExtractImageFilter
 */
namespace Functor {  
  
template< class TInput, class TOutput>
class Cast
{
public:
  Cast() {};
  ~Cast() {};
  bool operator!=( const Cast & ) const
  {
    return false;
  }
  bool operator==( const Cast & other ) const
  {
    return !(*this != other);
  }
  inline TOutput operator()( const TInput & A )
  {
    return static_cast<TOutput>( A );
  }
};
}

template <class TInputImage, class TOutputImage>
class ITK_EXPORT CastImageFilter :
    public
UnaryFunctorImageFilter<TInputImage,TOutputImage, 
                        Functor::Cast< 
  typename TInputImage::PixelType, 
  typename TOutputImage::PixelType> >
{
public:
  /** Standard class typedefs. */
  typedef CastImageFilter  Self;
  typedef UnaryFunctorImageFilter<TInputImage,TOutputImage, 
                                  Functor::Cast< 
    typename TInputImage::PixelType, 
    typename TOutputImage::PixelType>   
  >  Superclass;
  typedef SmartPointer<Self>   Pointer;
  typedef SmartPointer<const Self>  ConstPointer;

  /** Method for creation through the object factory. */
  itkNewMacro(Self);
  
  /** Run-time type information (and related methods). */
  itkTypeMacro(CastImageFilter, UnaryFunctorImageFilter);

#ifdef ITK_USE_CONCEPT_CHECKING
  /** Begin concept checking */
  itkConceptMacro(InputConvertibleToOutputCheck,
    (Concept::Convertible<typename TInputImage::PixelType,
                          typename TOutputImage::PixelType>));
  /** End concept checking */
#endif

protected:
  CastImageFilter() {}
  virtual ~CastImageFilter() {}

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

};


} // end namespace itk

#endif
