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

  Program:   Insight Segmentation & Registration Toolkit
  Module:    $RCSfile: itkHMinimaImageFilter.h,v $
  Language:  C++
  Date:      $Date: 2006/03/28 19:59:05 $
  Version:   $Revision: 1.6 $

  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 __itkHMinimaImageFilter_h
#define __itkHMinimaImageFilter_h

#include "itkImageToImageFilter.h"

namespace itk {

/** \class HMinimaImageFilter
 * \brief Suppress local minima whose depth below the baseline is less than h.
 *
 * HMinimaImageFilter suppresses local minima that are less than h
 * intensity units below the (local) background. This has the effect
 * of smoothing over the "low" parts of the noise in the image
 * without smoothing over large changes in intensity (region
 * boundaries). See the HMaximaImageFilter to suppress the local
 * maxima whose height is less than h intensity units above the (local)
 * background.
 *
 * If original image is subtracted from the output of
 * HMinimaImageFilter, the signicant "valleys" in the image can be
 * identified.  This is what the HConcaveImageFilter provides.
 *
 * This filter uses the GrayscaleGeodesicErodeImageFilter.  It
 * provides its own input as the "mask" input to the geodesic
 * dilation.  The "marker" image for the geodesic dilation is
 * the input image plus the height parameter h.
 *
 * Geodesic morphology and the H-Minima algorithm is described in
 * Chapter 6 of Pierre Soille's book "Morphological Image Analysis:
 * Principles and Applications", Second Edition, Springer, 2003.
 *
 * \sa GrayscaleGeodesicDilateImageFilter, HMinimaImageFilter, HConvexImageFilter
 * \sa MorphologyImageFilter, GrayscaleDilateImageFilter, GrayscaleFunctionDilateImageFilter, BinaryDilateImageFilter
 * \ingroup ImageEnhancement  MathematicalMorphologyImageFilters
 */
template<class TInputImage, class TOutputImage>
class ITK_EXPORT HMinimaImageFilter : 
    public ImageToImageFilter<TInputImage, TOutputImage>
{
public:
  /** Standard class typedefs. */
  typedef HMinimaImageFilter Self;
  typedef ImageToImageFilter<TInputImage, TOutputImage>
  Superclass;
  typedef SmartPointer<Self>        Pointer;
  typedef SmartPointer<const Self>  ConstPointer;

  /** Some convenient typedefs. */
  typedef TInputImage InputImageType;
  typedef TOutputImage OutputImageType;
  typedef typename InputImageType::Pointer         InputImagePointer;
  typedef typename InputImageType::ConstPointer    InputImageConstPointer;
  typedef typename InputImageType::RegionType      InputImageRegionType;
  typedef typename InputImageType::PixelType       InputImagePixelType;
  typedef typename OutputImageType::Pointer        OutputImagePointer;
  typedef typename OutputImageType::ConstPointer   OutputImageConstPointer;
  typedef typename OutputImageType::RegionType     OutputImageRegionType;
  typedef typename OutputImageType::PixelType      OutputImagePixelType;
  
  /** ImageDimension constants */
  itkStaticConstMacro(InputImageDimension, unsigned int,
                      TInputImage::ImageDimension);
  itkStaticConstMacro(OutputImageDimension, unsigned int,
                      TOutputImage::ImageDimension);

  /** Standard New method. */
  itkNewMacro(Self);  

  /** Runtime information support. */
  itkTypeMacro(HMinimaImageFilter, 
               ImageToImageFilter);

  /** Set/Get the height that a local maximum must be above the local
   * background (local contrast) in order to survive the
   * processing. Local maxima below this value are replaced with an
   * estimate of the local background. */
  itkSetMacro(Height, InputImagePixelType);
  itkGetMacro(Height, InputImagePixelType);
  
  /** \deprecated
   * Get the number of iterations used to produce the current
   * output. This method is scheduled for removal since the
   * implementation now uses a noniterative solution. */
  unsigned long GetNumberOfIterationsUsed()
    { itkLegacyBody(itk::HMinimaImageFilter::GetNumberOfIterationsUsed, 2.2);
      return m_NumberOfIterationsUsed; };

  /**
   * Set/Get whether the connected components are defined strictly by
   * face connectivity or by face+edge+vertex connectivity.  Default is
   * FullyConnectedOff.  For objects that are 1 pixel wide, use
   * FullyConnectedOn.
   */
  itkSetMacro(FullyConnected, bool);
  itkGetConstReferenceMacro(FullyConnected, bool);
  itkBooleanMacro(FullyConnected);
  
#ifdef ITK_USE_CONCEPT_CHECKING
  /** Begin concept checking */
  itkConceptMacro(InputEqualityComparableCheck,
    (Concept::EqualityComparable<InputImagePixelType>));
  itkConceptMacro(IntConvertibleToInputCheck,
    (Concept::Convertible<int, InputImagePixelType>));
  itkConceptMacro(InputOStreamWritableCheck,
    (Concept::OStreamWritable<InputImagePixelType>));
  /** End concept checking */
#endif

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

  /** HMinimaImageFilter needs the entire input be
   * available. Thus, it needs to provide an implementation of
   * GenerateInputRequestedRegion(). */
  void GenerateInputRequestedRegion() ;

  /** HMinimaImageFilter will produce the entire output. */
  void EnlargeOutputRequestedRegion(DataObject *itkNotUsed(output));
  
  /** Single-threaded version of GenerateData.  This filter delegates
   * to GrayscaleGeodesicErodeImageFilter. */
  void GenerateData();
  

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

  InputImagePixelType m_Height;
  unsigned long m_NumberOfIterationsUsed;
  bool                m_FullyConnected;
} ; // end of class

} // end namespace itk
  
#ifndef ITK_MANUAL_INSTANTIATION
#include "itkHMinimaImageFilter.txx"
#endif

#endif


