itkCannyEdgeDetectionImageFilter.h

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

  Program:   Insight Segmentation & Registration Toolkit
  Module:    $RCSfile: itkCannyEdgeDetectionImageFilter.h,v $
  Language:  C++
  Date:      $Date: 2005/08/08 16:20:11 $
  Version:   $Revision: 1.19 $

  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 __itkCannyEdgeDetectionImageFilter_h
#define __itkCannyEdgeDetectionImageFilter_h

#include "itkImageToImageFilter.h"
#include "itkImage.h"
#include "itkFixedArray.h"
#include "itkConstNeighborhoodIterator.h"
#include "itkZeroFluxNeumannBoundaryCondition.h"
#include "itkMultiThreader.h"
#include "itkDerivativeOperator.h"
#include "itkSparseFieldLayer.h"
#include "itkObjectStore.h"


namespace itk
{


template <class TValueType>
class ListNode
{
public:
  TValueType m_Value;
  ListNode *Next;
  ListNode *Previous;
};


template<class TInputImage, class TOutputImage>
class ITK_EXPORT CannyEdgeDetectionImageFilter
  : public ImageToImageFilter<TInputImage, TOutputImage>
{
public:
  typedef CannyEdgeDetectionImageFilter    Self;
  typedef ImageToImageFilter<TInputImage, TOutputImage> Superclass;
   
  typedef TInputImage  InputImageType;
  typedef TOutputImage OutputImageType;
      
  typedef SmartPointer<Self>  Pointer;
  typedef SmartPointer<const Self>  ConstPointer;

  typedef typename TInputImage::PixelType  InputImagePixelType;
  typedef typename TOutputImage::PixelType  OutputImagePixelType;
  typedef typename TInputImage::IndexType   IndexType;

  typedef ZeroFluxNeumannBoundaryCondition<OutputImageType>
  DefaultBoundaryConditionType;

  typedef ConstNeighborhoodIterator<OutputImageType,
                                    DefaultBoundaryConditionType> NeighborhoodType;

  typedef ListNode<IndexType> ListNodeType;
  typedef ObjectStore<ListNodeType> ListNodeStorageType;
  typedef SparseFieldLayer<ListNodeType> ListType;
  typedef typename ListType::Pointer ListPointerType;

  itkNewMacro(Self);  
    
  typedef typename TOutputImage::RegionType OutputImageRegionType;
    
  itkTypeMacro(CannyEdgeDetectionImageFilter, ImageToImageFilter);
  
  itkStaticConstMacro(ImageDimension, unsigned int,
                      TInputImage::ImageDimension);
  
  typedef FixedArray<double, itkGetStaticConstMacro(ImageDimension)> ArrayType;

  itkSetMacro(Variance, ArrayType);
  itkGetMacro(Variance, const ArrayType);
  itkSetMacro(MaximumError, ArrayType);
  itkGetMacro(MaximumError, const ArrayType);
  
  void SetVariance(const typename ArrayType::ValueType v)
  {
    for (unsigned int i=0; i < TInputImage::ImageDimension; i++)
      {
      if (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 (m_Variance[i] != v)
        {
        m_MaximumError.Fill(v);
        this->Modified();
        break;
        }
      }
  }
  
  /* Set the Threshold value for detected edges. */
  void SetThreshold(const OutputImagePixelType th)
  {
    this->m_Threshold = th;
    this->m_UpperThreshold = m_Threshold;
    this->m_LowerThreshold = m_Threshold/2.0;
    itkLegacyReplaceBody(SetThreshold, 2.2, SetUpperThreshold);
  }
  
  OutputImagePixelType GetThreshold(OutputImagePixelType th) 
  {
    itkLegacyReplaceBody(GetThreshold, 2.2, GetUpperThreshold);
    return this->m_Threshold; 
  }

  itkSetMacro(UpperThreshold, OutputImagePixelType );
  itkGetMacro(UpperThreshold, OutputImagePixelType);

  itkSetMacro(LowerThreshold, OutputImagePixelType );
  itkGetMacro(LowerThreshold, OutputImagePixelType);

  /* Set the Thresholdvalue for detected edges. */
  itkSetMacro(OutsideValue, OutputImagePixelType);
  itkGetMacro(OutsideValue, OutputImagePixelType);
  
  virtual void GenerateInputRequestedRegion() throw(InvalidRequestedRegionError);

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

  void GenerateData();

private:
  virtual ~CannyEdgeDetectionImageFilter(){};

  struct CannyThreadStruct
  {
    CannyEdgeDetectionImageFilter *Filter;
  };

  void AllocateUpdateBuffer();

  void HysteresisThresholding();

  void FollowEdge(IndexType index);

  bool InBounds(IndexType index);
  

  void Compute2ndDerivative();

  //  virtual
  //  int SplitUpdateContainer(int i, int num, ThreadRegionType& splitRegion);

  void ThreadedCompute2ndDerivative(const OutputImageRegionType&
                                    outputRegionForThread, int threadId);

  static ITK_THREAD_RETURN_TYPE
  Compute2ndDerivativeThreaderCallback( void * arg );

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

  void Compute2ndDerivativePos();

  void ThreadedCompute2ndDerivativePos(const OutputImageRegionType&
                                       outputRegionForThread, int threadId);

  static ITK_THREAD_RETURN_TYPE
  Compute2ndDerivativePosThreaderCallback( void *arg );

  ArrayType m_Variance;

  ArrayType m_MaximumError;

  OutputImagePixelType m_UpperThreshold;  //should be float here?
  
  OutputImagePixelType m_LowerThreshold; //should be float here?

  OutputImagePixelType m_Threshold;

  OutputImagePixelType m_OutsideValue;

  typename OutputImageType::Pointer  m_UpdateBuffer;
  typename OutputImageType::Pointer  m_UpdateBuffer1;

  DerivativeOperator<OutputImagePixelType,itkGetStaticConstMacro(ImageDimension)>
  m_ComputeCannyEdge1stDerivativeOper;
  DerivativeOperator<OutputImagePixelType,itkGetStaticConstMacro(ImageDimension)>
  m_ComputeCannyEdge2ndDerivativeOper;

  std::slice  m_ComputeCannyEdgeSlice[ImageDimension];

  unsigned long m_Stride[ImageDimension];
  unsigned long m_Center;

  typename ListNodeStorageType::Pointer m_NodeStore;
  ListPointerType m_NodeList;

};

} //end of namespace itk

#ifndef ITK_MANUAL_INSTANTIATION
#include "itkCannyEdgeDetectionImageFilter.txx"
#endif
  
#endif

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