/*=========================================================================
 *
 *  Copyright Insight Software Consortium
 *
 *  Licensed under the Apache License, Version 2.0 (the "License");
 *  you may not use this file except in compliance with the License.
 *  You may obtain a copy of the License at
 *
 *         http://www.apache.org/licenses/LICENSE-2.0.txt
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS,
 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 *
 *=========================================================================*/
#ifndef itkValuedRegionalMinimaImageFilter_h
#define itkValuedRegionalMinimaImageFilter_h

#include "itkValuedRegionalExtremaImageFilter.h"
#include "itkConceptChecking.h"

namespace itk
{
/** \class ValuedRegionalMinimaImageFilter
 *
 * \brief Transforms the image so that any pixel that is not a
 * regional minima is set to the maximum value for the pixel
 * type. Pixels that are regional minima retain their value.
 *
 * Regional minima are flat zones surrounded by pixels of higher
 * value. A completely flat image will be marked as a regional minima
 * by this filter.
 *
 * This code was contributed in the Insight Journal paper:
 * "Finding regional extrema - methods and performance"
 * by Beare R., Lehmann G.
 * https://hdl.handle.net/1926/153
 * http://www.insight-journal.org/browse/publication/65
 *
 * \author Richard Beare. Department of Medicine, Monash University,
 * Melbourne, Australia.
 *
 * \sa ValuedRegionalMaximaImageFilter, ValuedRegionalExtremaImageFilter,
 * \sa HMinimaImageFilter
 * \ingroup MathematicalMorphologyImageFilters
 * \ingroup ITKMathematicalMorphology
 *
 * \wiki
 * \wikiexample{ImageProcessing/ValuedRegionalMinimaImageFilter,ValuedRegionalMinimaImageFilter}
 * \endwiki
 */
template< typename TInputImage, typename TOutputImage >
class ValuedRegionalMinimaImageFilter:
  public
  ValuedRegionalExtremaImageFilter< TInputImage, TOutputImage,
                                    std::less< typename TInputImage::PixelType >,
                                    std::less< typename TOutputImage::PixelType >
                                    >
{
public:
  ITK_DISALLOW_COPY_AND_ASSIGN(ValuedRegionalMinimaImageFilter);

  using Self = ValuedRegionalMinimaImageFilter;

  using Superclass = ValuedRegionalExtremaImageFilter< TInputImage, TOutputImage,
                                            std::less< typename TInputImage::PixelType >,
                                            std::less< typename TOutputImage::PixelType >  >;

  using Pointer = SmartPointer< Self >;
  using ConstPointer = SmartPointer< const Self >;

  using InputImageType = TInputImage;
  using InputImagePixelType = typename InputImageType::PixelType;

  /** Method for creation through the object factory. */
  itkNewMacro(Self);

  /** Runtime information support. */
  itkTypeMacro(ValuedRegionalMinimaImageFilter,
               ValuedRegionalExtremaImageFilter);

#ifdef ITK_USE_CONCEPT_CHECKING
  // Begin concept checking
  itkConceptMacro( InputPixelTypeComparable,
                   ( Concept::LessThanComparable< InputImagePixelType > ) );
  itkConceptMacro( InputHasPixelTraitsCheck,
                   ( Concept::HasPixelTraits< InputImagePixelType > ) );
  itkConceptMacro( InputHasNumericTraitsCheck,
                   ( Concept::HasNumericTraits< InputImagePixelType > ) );
  // End concept checking
#endif

protected:
  ValuedRegionalMinimaImageFilter()
  {
    this->SetMarkerValue( NumericTraits< typename TOutputImage::PixelType >::max() );
  }

  ~ValuedRegionalMinimaImageFilter() override = default;
};                                               // end
                                                 // ValuedRegionalMinimaImageFilter
} //end namespace itk
#endif
