/*=========================================================================
 *
 *  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 itkGradientAnisotropicDiffusionImageFilter_h
#define itkGradientAnisotropicDiffusionImageFilter_h

#include "itkAnisotropicDiffusionImageFilter.h"
#include "itkGradientNDAnisotropicDiffusionFunction.h"

namespace itk
{
/** \class GradientAnisotropicDiffusionImageFilter
 *
 * This filter performs anisotropic diffusion on a scalar itk::Image using the
 * classic Perona-Malik, gradient magnitude based equation implemented in
 * itkGradientNDAnisotropicDiffusionFunction.  For detailed information on
 * anisotropic diffusion, see itkAnisotropicDiffusionFunction and
 * itkGradientNDAnisotropicDiffusionFunction.
 *
 * \par Inputs and Outputs
 * The input to this filter should be a scalar itk::Image of any
 * dimensionality.  The output image will be a diffused copy of the input.

 * \par Parameters
 * Please see the description of parameters given in
 * itkAnisotropicDiffusionImageFilter.
 *
 * \sa AnisotropicDiffusionImageFilter
 * \sa AnisotropicDiffusionFunction
 * \sa GradientAnisotropicDiffusionFunction
 * \ingroup ImageEnhancement
 * \ingroup ImageFilters
 * \ingroup ITKAnisotropicSmoothing
 */
template< typename TInputImage, typename TOutputImage >
class ITK_TEMPLATE_EXPORT GradientAnisotropicDiffusionImageFilter:
  public AnisotropicDiffusionImageFilter< TInputImage, TOutputImage >
{
public:
  ITK_DISALLOW_COPY_AND_ASSIGN(GradientAnisotropicDiffusionImageFilter);

  /** Standard class type aliases. */
  using Self = GradientAnisotropicDiffusionImageFilter;
  using Superclass =
      AnisotropicDiffusionImageFilter< TInputImage, TOutputImage >;
  using Pointer = SmartPointer< Self >;
  using ConstPointer = SmartPointer< const Self >;

  /** Standard method for creation through object factory. */
  itkNewMacro(Self);

  /** Run-time class information. */
  itkTypeMacro(GradientAnisotropicDiffusionImageFilter,
               AnisotropicDiffusionImageFilter);

  /** Extract information from the superclass. */
  using UpdateBufferType = typename Superclass::UpdateBufferType;

  /** Extract information from the superclass. */
  static constexpr unsigned int ImageDimension = Superclass::ImageDimension;

#ifdef ITK_USE_CONCEPT_CHECKING
  // Begin concept checking
  itkConceptMacro( UpdateBufferHasNumericTraitsCheck,
                   ( Concept::HasNumericTraits< typename UpdateBufferType::PixelType > ) );
  // End concept checking
#endif

protected:
  GradientAnisotropicDiffusionImageFilter()
  {
    typename GradientNDAnisotropicDiffusionFunction< UpdateBufferType >::Pointer p =
      GradientNDAnisotropicDiffusionFunction< UpdateBufferType >::New();
    this->SetDifferenceFunction(p);
  }

  ~GradientAnisotropicDiffusionImageFilter() override = default;
};
} // end namspace itk

#endif
