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

  Program:   Insight Segmentation & Registration Toolkit
  Module:    $RCSfile: itkProjectionImageFilter.h,v $
  Language:  C++
  Date:      $Date: 2009-01-28 18:14:36 $
  Version:   $Revision: 1.2 $

  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 __itkProjectionImageFilter_h
#define __itkProjectionImageFilter_h

#include "itkImageToImageFilter.h"
#include "itkConceptChecking.h"

namespace itk
{
  
/** \class ProjectionImageFilter
 * \brief Implements an accumulation of an image along a selected direction.
 *
 * This class accumulates an image along a dimension and reduces the
 * size of this dimension to 1. The dimension being accumulated is set
 * by ProjectionDimension. 
 *
 * Each pixel is the cumulative sum of the pixels along the collapsed
 * dimension and reduces the size of the accumulated dimension to 1 (only 
 * on the accumulated). 
 *
 * The dimensions of the InputImage and the OutputImage must be the same.
 *
 * This class is parameterized over the type of the input image and
 * the type of the output image.
 *
 * This class was contributed to the Insight Journal by Emilian Beronich and
 * Gaetan Lehmann. The original paper can be found at 
 *      http://insight-journal.org/midas/handle.php?handle=1926/164
 *
 * \author Emiliano Beronich
 * \author Gaetan Lehmann. Biologie du Developpement et de la Reproduction,
 * INRA de Jouy-en-Josas, France.
 *
 *
 * \sa AccumulateImageFilter
 * \ingroup   IntensityImageFilters     Singlethreaded
 */
template <class TInputImage, class TOutputImage, class TAccumulator>
class ITK_EXPORT ProjectionImageFilter : 
  public ImageToImageFilter<TInputImage,TOutputImage>
{
public:
  /** Standard class typedefs. */
  typedef ProjectionImageFilter                         Self;
  typedef ImageToImageFilter<TInputImage,TOutputImage>  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(ProjectionImageFilter, ImageToImageFilter);

  /** Some convenient typedefs. */
  typedef TInputImage                              InputImageType;
  typedef typename    InputImageType::Pointer      InputImagePointer;
  typedef typename    InputImageType::RegionType   InputImageRegionType;
  typedef typename    InputImageType::PixelType    InputImagePixelType;
  typedef TOutputImage                             OutputImageType;
  typedef typename     OutputImageType::Pointer    OutputImagePointer;
  typedef typename     OutputImageType::RegionType OutputImageRegionType;
  typedef typename     OutputImageType::PixelType  OutputImagePixelType;

  typedef TAccumulator AccumulatorType;

  /** ImageDimension enumeration */
  itkStaticConstMacro(InputImageDimension, unsigned int,
                      TInputImage::ImageDimension);
  itkStaticConstMacro(OutputImageDimension, unsigned int,
                      TOutputImage::ImageDimension);

  /** Input and output images must be the same dimension, or the output's
      dimension must be one less than that of the input. */
#ifdef ITK_USE_CONCEPT_CHECKING
  /** Begin concept checking */
  itkConceptMacro(ImageDimensionCheck,
    (Concept::SameDimensionOrMinusOne<
       itkGetStaticConstMacro(InputImageDimension),
       itkGetStaticConstMacro(OutputImageDimension)>));
  /** End concept checking */
#endif


  /** Set/Get the direction in which to accumulate the data.  It must be set
   * before the update of the filter. Defaults to the last dimension. */
  itkSetMacro( ProjectionDimension, unsigned int );
  itkGetConstReferenceMacro( ProjectionDimension, unsigned int );


protected:
  ProjectionImageFilter();
  virtual ~ProjectionImageFilter() {};
  void PrintSelf(std::ostream& os, Indent indent) const;

  /** Apply changes to the output image information. */
  virtual void GenerateOutputInformation();

  /** Apply changes to the input image requested region. */
  virtual void GenerateInputRequestedRegion();

  virtual void ThreadedGenerateData( 
   const OutputImageRegionType& outputRegionForThread, int threadId );

  virtual AccumulatorType NewAccumulator( unsigned long ) const;

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

  unsigned int m_ProjectionDimension;

};

} // end namespace itk

#ifndef ITK_MANUAL_INSTANTIATION
#include "itkProjectionImageFilter.txx"
#endif

#endif
