itkImageToListSampleAdaptor.h

Go to the documentation of this file.

/*=========================================================================
 *
 *  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 itkImageToListSampleAdaptor_h
#define itkImageToListSampleAdaptor_h
 
#include <typeinfo>
#include <utility>
 
#include "itkImage.h"
#include "itkPixelTraits.h"
#include "itkListSample.h"
#include "itkSmartPointer.h"
#include "itkImageRegionIterator.h"
#include "itkMeasurementVectorTraits.h"
 
namespace itk::Statistics
{
 
template <typename TImage>
class ITK_TEMPLATE_EXPORT ImageToListSampleAdaptor
  : public ListSample<typename MeasurementVectorPixelTraits<typename TImage::PixelType>::MeasurementVectorType>
{
public:
  ITK_DISALLOW_COPY_AND_MOVE(ImageToListSampleAdaptor);

  using Self = ImageToListSampleAdaptor;
 
  using Superclass =
    ListSample<typename MeasurementVectorPixelTraits<typename TImage::PixelType>::MeasurementVectorType>;
 
  using Pointer = SmartPointer<Self>;
  using ConstPointer = SmartPointer<const Self>;

  itkOverrideGetNameOfClassMacro(ImageToListSampleAdaptor);

  itkNewMacro(Self);

  using ImageType = TImage;
  using ImagePointer = typename ImageType::Pointer;
  using ImageConstPointer = typename ImageType::ConstPointer;
  using IndexType = typename ImageType::IndexType;
  using PixelType = typename ImageType::PixelType;
  using PixelContainerConstPointer = typename ImageType::PixelContainerConstPointer;

  using ImageIteratorType = ImageRegionIterator<ImageType>;
  using ImageConstIteratorType = ImageRegionConstIterator<ImageType>;
  using PixelTraitsType = PixelTraits<typename TImage::PixelType>;
 

  using MeasurementPixelTraitsType = MeasurementVectorPixelTraits<PixelType>;
  using MeasurementVectorType = typename MeasurementPixelTraitsType::MeasurementVectorType;
 
  using MeasurementVectorTraitsType = MeasurementVectorTraitsTypes<MeasurementVectorType>;
  using MeasurementType = typename MeasurementVectorTraitsType::ValueType;
 
  using typename Superclass::AbsoluteFrequencyType;
  using typename Superclass::TotalAbsoluteFrequencyType;
  using typename Superclass::MeasurementVectorSizeType;
  using typename Superclass::InstanceIdentifier;
 
  using ValueType = MeasurementVectorType;

  void
  SetImage(const TImage * image);

  const TImage *
  GetImage() const;

  InstanceIdentifier
  Size() const override;

  const MeasurementVectorType &
  GetMeasurementVector(InstanceIdentifier id) const override;
 
  MeasurementVectorSizeType
  GetMeasurementVectorSize() const override
  {
    // some filter are expected that this method returns something even if the
    // input is not set. This won't be the right value for a variable length vector
    // but it's better than an exception.
    if (m_Image.IsNull())
    {
      return Superclass::GetMeasurementVectorSize();
    }
 
    return m_Image->GetNumberOfComponentsPerPixel();
  }

  AbsoluteFrequencyType
  GetFrequency(InstanceIdentifier id) const override;

  TotalAbsoluteFrequencyType
  GetTotalFrequency() const override;

  class ConstIterator
  {
    friend class ImageToListSampleAdaptor;
 
  public:
    ConstIterator() = delete;
 
    ConstIterator(const ImageToListSampleAdaptor * adaptor) { *this = adaptor->Begin(); }
 
    ConstIterator(const ConstIterator & iter)
      : m_Iter(iter.m_Iter)
      , m_InstanceIdentifier(iter.m_InstanceIdentifier)
    {}
 
    ConstIterator &
    operator=(const ConstIterator & iter)
    {
      m_Iter = iter.m_Iter;
      m_InstanceIdentifier = iter.m_InstanceIdentifier;
      return *this;
    }
 
    AbsoluteFrequencyType
    GetFrequency() const
    {
      return 1;
    }
 
    const MeasurementVectorType &
    GetMeasurementVector() const
    {
      MeasurementVectorTraits::Assign(this->m_MeasurementVectorCache, m_Iter.Get());
      return this->m_MeasurementVectorCache;
    }
 
    InstanceIdentifier
    GetInstanceIdentifier() const
    {
      return m_InstanceIdentifier;
    }
 
    ConstIterator &
    operator++()
    {
      ++m_Iter;
      ++m_InstanceIdentifier;
      return *this;
    }
 
    bool
    operator==(const ConstIterator & it) const
    {
      return (m_Iter == it.m_Iter);
    }
 
    ITK_UNEQUAL_OPERATOR_MEMBER_FUNCTION(ConstIterator);
 
  protected:
    // This method should only be available to the ListSample class
    ConstIterator(ImageConstIteratorType iter, InstanceIdentifier iid)
      : m_Iter(std::move(iter))
      , m_InstanceIdentifier(iid)
    {}
 
  private:
    ImageConstIteratorType        m_Iter;
    mutable MeasurementVectorType m_MeasurementVectorCache;
    InstanceIdentifier            m_InstanceIdentifier;
  };

  class Iterator : public ConstIterator
  {
    friend class ImageToListSampleAdaptor;
 
  public:
    Iterator() = delete;
    Iterator(const Self * adaptor) = delete;
    Iterator(const ImageConstIteratorType & iter, InstanceIdentifier iid) = delete;
    Iterator(const ConstIterator & it) = delete;
    ConstIterator &
    operator=(const ConstIterator & it) = delete;
 
    Iterator(Self * adaptor)
      : ConstIterator(adaptor)
    {}
 
    Iterator(const Iterator & iter)
      : ConstIterator(iter)
    {}
 
    Iterator &
    operator=(const Iterator & iter)
    {
      this->ConstIterator::operator=(iter);
      return *this;
    }
 
  protected:
    Iterator(const ImageIteratorType & iter, InstanceIdentifier iid)
      : ConstIterator(iter, iid)
    {}
  };

  Iterator
  Begin()
  {
    const ImagePointer nonConstImage = const_cast<ImageType *>(m_Image.GetPointer());
    ImageIteratorType  imageIterator(nonConstImage, nonConstImage->GetLargestPossibleRegion());
    imageIterator.GoToBegin();
    const Iterator iter(imageIterator, 0);
    return iter;
  }

  Iterator
  End()
  {
    const ImagePointer                     nonConstImage = const_cast<ImageType *>(m_Image.GetPointer());
    const typename ImageType::RegionType & largestRegion = nonConstImage->GetLargestPossibleRegion();
    ImageIteratorType                      imageIterator(nonConstImage, largestRegion);
    imageIterator.GoToEnd();
    const Iterator iter(imageIterator, largestRegion.GetNumberOfPixels());
 
    return iter;
  }

  ConstIterator
  Begin() const
  {
    ImageConstIteratorType imageConstIterator(m_Image, m_Image->GetLargestPossibleRegion());
    imageConstIterator.GoToBegin();
    const ConstIterator iter(imageConstIterator, 0);
 
    return iter;
  }

  ConstIterator
  End() const
  {
    const typename ImageType::RegionType & largestRegion = m_Image->GetLargestPossibleRegion();
    ImageConstIteratorType                 imageConstIterator(m_Image, largestRegion);
    imageConstIterator.GoToEnd();
    const ConstIterator iter(imageConstIterator, largestRegion.GetNumberOfPixels());
 
    return iter;
  }
 
protected:
  ImageToListSampleAdaptor();
  ~ImageToListSampleAdaptor() override = default;
  void
  PrintSelf(std::ostream & os, Indent indent) const override;
 
private:
  ImageConstPointer             m_Image{};
  mutable MeasurementVectorType m_MeasurementVectorInternal{};
 
}; // end of class ImageToListSampleAdaptor
} // namespace itk::Statistics
 
#ifndef ITK_MANUAL_INSTANTIATION
#  include "itkImageToListSampleAdaptor.hxx"
#endif
 
#endif