itkCannyEdgeDetectionImageFilter.h

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/*=========================================================================
 *
 *  Copyright NumFOCUS
 *
 *  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
 *
 *         https://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 itkCannyEdgeDetectionImageFilter_h
#define itkCannyEdgeDetectionImageFilter_h
 
#include "itkConstNeighborhoodIterator.h"
#include "itkDiscreteGaussianImageFilter.h"
#include "itkMultiplyImageFilter.h"
#include "itkMultiThreaderBase.h"
#include "itkDerivativeOperator.h"
#include "itkSparseFieldLayer.h"
#include "itkObjectStore.h"
#include "itkMath.h"
 
namespace itk
{
template <typename TValue>
class ITK_TEMPLATE_EXPORT ListNode
{
public:
  TValue m_Value;
 
  ListNode * Next;
  ListNode * Previous;
};

template <typename TInputImage, typename TOutputImage>
class ITK_TEMPLATE_EXPORT CannyEdgeDetectionImageFilter : public ImageToImageFilter<TInputImage, TOutputImage>
{
public:
  ITK_DISALLOW_COPY_AND_MOVE(CannyEdgeDetectionImageFilter);

  using Self = CannyEdgeDetectionImageFilter;
  using Superclass = ImageToImageFilter<TInputImage, TOutputImage>;

  using InputImageType = TInputImage;
  using OutputImageType = TOutputImage;

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

  using InputImagePixelType = typename TInputImage::PixelType;
  using OutputImagePixelType = typename TOutputImage::PixelType;
  using IndexType = typename TInputImage::IndexType;
  using SizeValueType = typename TInputImage::SizeValueType;

  using DefaultBoundaryConditionType = ZeroFluxNeumannBoundaryCondition<OutputImageType>;

  using NeighborhoodType = ConstNeighborhoodIterator<OutputImageType, DefaultBoundaryConditionType>;
 
  using ListNodeType = ListNode<IndexType>;
  using ListNodeStorageType = ObjectStore<ListNodeType>;
  using ListType = SparseFieldLayer<ListNodeType>;
  using ListPointerType = typename ListType::Pointer;

  itkNewMacro(Self);

  using OutputImageRegionType = typename TOutputImage::RegionType;
  using InputImageRegionType = typename TInputImage::RegionType;

  itkOverrideGetNameOfClassMacro(CannyEdgeDetectionImageFilter);

  static constexpr unsigned int ImageDimension = TInputImage::ImageDimension;
  static constexpr unsigned int OutputImageDimension = TOutputImage::ImageDimension;

  using ArrayType = FixedArray<double, Self::ImageDimension>;

  itkSetMacro(Variance, ArrayType);
  itkGetConstMacro(Variance, const ArrayType);

  itkSetMacro(MaximumError, ArrayType);
  itkGetConstMacro(MaximumError, const ArrayType);

  void
  SetVariance(const typename ArrayType::ValueType v)
  {
    for (unsigned int i = 0; i < TInputImage::ImageDimension; ++i)
    {
      if (Math::NotExactlyEquals(m_Variance[i], v))
      {
        m_Variance.Fill(v);
        this->Modified();
        break;
      }
    }
  }


  void
  SetMaximumError(const typename ArrayType::ValueType v)
  {
    for (unsigned int i = 0; i < TInputImage::ImageDimension; ++i)
    {
      if (Math::NotExactlyEquals(m_MaximumError[i], v))
      {
        m_MaximumError.Fill(v);
        this->Modified();
        break;
      }
    }
  }


  itkSetMacro(UpperThreshold, OutputImagePixelType);
  itkGetConstMacro(UpperThreshold, OutputImagePixelType);

  itkSetMacro(LowerThreshold, OutputImagePixelType);
  itkGetConstMacro(LowerThreshold, OutputImagePixelType);
 
  OutputImageType *
  GetNonMaximumSuppressionImage()
  {
    return this->m_MultiplyImageFilter->GetOutput();
  }
 
  itkConceptMacro(InputHasNumericTraitsCheck, (Concept::HasNumericTraits<InputImagePixelType>));
  itkConceptMacro(OutputHasNumericTraitsCheck, (Concept::HasNumericTraits<OutputImagePixelType>));
  itkConceptMacro(SameDimensionCheck, (Concept::SameDimension<ImageDimension, OutputImageDimension>));
  itkConceptMacro(InputIsFloatingPointCheck, (Concept::IsFloatingPoint<InputImagePixelType>));
  itkConceptMacro(OutputIsFloatingPointCheck, (Concept::IsFloatingPoint<OutputImagePixelType>));
 
protected:
  CannyEdgeDetectionImageFilter();
  void
  PrintSelf(std::ostream & os, Indent indent) const override;
 
  void
  GenerateData() override;
 
  using GaussianImageFilterType = DiscreteGaussianImageFilter<InputImageType, OutputImageType>;
  using MultiplyImageFilterType = MultiplyImageFilter<OutputImageType, OutputImageType, OutputImageType>;
 
private:
  ~CannyEdgeDetectionImageFilter() override = default;

  void
  AllocateUpdateBuffer();

  void
  HysteresisThresholding();

  void
  FollowEdge(IndexType index, const OutputImageType * multiplyImageFilterOutput);

  void
  ThreadedCompute2ndDerivative(const OutputImageRegionType & outputRegionForThread);
 

  OutputImagePixelType
  ComputeCannyEdge(const NeighborhoodType & it, void * globalData);

  void
  ThreadedCompute2ndDerivativePos(const OutputImageRegionType & outputRegionForThread);
 
  ArrayType m_Variance{};
  ArrayType m_MaximumError{};
 
  OutputImagePixelType m_UpperThreshold{}; // should be float here?
  OutputImagePixelType m_LowerThreshold{}; // should be float here?
 
  typename OutputImageType::Pointer m_UpdateBuffer1{};

  typename GaussianImageFilterType::Pointer m_GaussianFilter{};

  typename MultiplyImageFilterType::Pointer m_MultiplyImageFilter{};

  DerivativeOperator<OutputImagePixelType, Self::ImageDimension> m_ComputeCannyEdge1stDerivativeOper{};
  DerivativeOperator<OutputImagePixelType, Self::ImageDimension> m_ComputeCannyEdge2ndDerivativeOper{};
 
  std::slice m_ComputeCannyEdgeSlice[ImageDimension]{};
 
  SizeValueType m_Stride[ImageDimension]{};
  SizeValueType m_Center{};
 
  typename ListNodeStorageType::Pointer m_NodeStore{};
  ListPointerType                       m_NodeList{};
 
  OutputImageType * m_OutputImage{};
};
} // end of namespace itk
 
#ifndef ITK_MANUAL_INSTANTIATION
#  include "itkCannyEdgeDetectionImageFilter.hxx"
#endif
 
#endif