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

  Program:   Insight Segmentation & Registration Toolkit
  Module:    $RCSfile: itkComplexToPhaseImageAdaptor.h,v $
  Language:  C++
  Date:      $Date: 2006/03/19 23:24:29 $
  Version:   $Revision: 1.4 $

  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 __itkComplexToPhaseImageAdaptor_h
#define __itkComplexToPhaseImageAdaptor_h

#include <itkImageAdaptor.h>
#include <complex>

namespace itk
{
 
namespace Accessor {
/** \class ComplexToPhasePixelAccessor
 * \brief Give access to the Phase part of a std::complex<> value 
 *
 * ComplexToPhasePixelAccessor is templated over an internal type and an
 * external type representation. The internal type is an std::complex<T> and
 * the external part is a type T. This class cast the input applies the funtion
 * to it and cast the result according to the types defined as template
 * parameters
 *
 * \ingroup ImageAdaptors
 */
template <class TInternalType, class TExternalType >
class ITK_EXPORT ComplexToPhasePixelAccessor  
{
public:
  /** External typedef. It defines the external aspect
   * that this class will exhibit. */
  typedef TExternalType ExternalType;

  /** Internal typedef. It defines the internal phase
   * representation of data. */
  typedef TInternalType InternalType;

  static inline void Set(TInternalType & output, const TExternalType & input) 
    {output = (TInternalType)(input);}

  static inline TExternalType Get( const TInternalType & input ) 
    {return (TExternalType)( vcl_atan2(input.imag(), input.real() ) );}
};
  
} // end namespace Accessor
 
/** \class ComplexToPhaseImageAdaptor
 * \brief Presents a complex image as being composed of arg() part of its pixels
 *
 * Additional casting is performed according to the input and output image
 * types following C++ default casting rules.
 *
 * \ingroup ImageAdaptors
 */
template <class TImage, class TOutputPixelType>
class ITK_EXPORT ComplexToPhaseImageAdaptor : public
      ImageAdaptor<TImage,
                   Accessor::ComplexToPhasePixelAccessor<
                                      typename TImage::PixelType,
                                      TOutputPixelType>   >
{
public:
  /** Standard class typedefs. */
  typedef ComplexToPhaseImageAdaptor                Self;
  typedef ImageAdaptor<TImage, Accessor::ComplexToPhasePixelAccessor<
                               typename TImage::PixelType,
                               TOutputPixelType> >  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( ComplexToPhaseImageAdaptor, ImageAdaptor );

protected:
  ComplexToPhaseImageAdaptor() {}
  virtual ~ComplexToPhaseImageAdaptor() {}
  
private:
  ComplexToPhaseImageAdaptor(const Self&); //purposely not implemented
  void operator=(const Self&); //purposely not implemented

};

} // end namespace itk

#endif
