text: /*=========================================================================
   *
   *  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 itkAbsImageAdaptor_h
  #define itkAbsImageAdaptor_h
  
  #include "itkImageAdaptor.h"
  
  namespace itk
  {
  namespace Accessor
  {
  /** \class AbsPixelAccessor
   * \brief Give access to the std::abs() function of a value
   *
   * AbsPixelAccessor is templated over an internal type and an
   * external type representation. This class cast the input
   * applies the function to it and cast the result according
   * to the types defined as template parameters
   *
   * \ingroup ImageAdaptors
   * \ingroup ITKImageAdaptors
   */
  template <typename TInternalType, typename TExternalType>
  class AbsPixelAccessor
  {
  public:
    /** External type alias. It defines the external aspect
     * that this class will exhibit. */
    using ExternalType = TExternalType;
  
    /** Internal type alias. It defines the internal real
     * representation of data. */
    using InternalType = TInternalType;
  
    static inline void
    Set(TInternalType & output, const TExternalType & input)
    {
      output = (TInternalType)((input > NumericTraits<TExternalType>::ZeroValue()) ? input : -input);
    }
  
    static inline TExternalType
    Get(const TInternalType & input)
    {
      return (TExternalType)((input > NumericTraits<TInternalType>::ZeroValue()) ? input : -input);
    }
  };
  } // end namespace Accessor
  
  /** \class AbsImageAdaptor
   * \brief Presents an image as being composed of the std::abs() of its pixels
   *
   * Additional casting is performed according to the input and output image
   * types following C++ default casting rules.
   *
   * \ingroup ImageAdaptors
   * \ingroup ITKImageAdaptors
   */
  template <typename TImage, typename TOutputPixelType>
  class AbsImageAdaptor
    : public ImageAdaptor<TImage, Accessor::AbsPixelAccessor<typename TImage::PixelType, TOutputPixelType>>
  {
  public:
    ITK_DISALLOW_COPY_AND_ASSIGN(AbsImageAdaptor);
  
    /** Standard class type aliases. */
    using Self = AbsImageAdaptor;
    using Superclass = ImageAdaptor<TImage, Accessor::AbsPixelAccessor<typename TImage::PixelType, TOutputPixelType>>;
  
    using Pointer = SmartPointer<Self>;
    using ConstPointer = SmartPointer<const Self>;
  
    /** Method for creation through the object factory. */
    itkNewMacro(Self);
  
    /** Run-time type information (and related methods). */
    itkTypeMacro(AbsImageAdaptor, ImageAdaptor);
  
  protected:
    AbsImageAdaptor() = default;
    ~AbsImageAdaptor() override = default;
  };
  } // end namespace itk
  
  #endif
  