itkMaskImageFilter.h

Go to the documentation of this file.

/*=========================================================================
 *
 *  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 __itkMaskImageFilter_h
#define __itkMaskImageFilter_h

#include "itkBinaryFunctorImageFilter.h"
#include "itkNumericTraits.h"
#include "itkVariableLengthVector.h"

namespace itk
{
namespace Functor
{
template< class TInput, class TMask, class TOutput = TInput >
class MaskInput
{
public:
  typedef typename NumericTraits< TInput >::AccumulateType AccumulatorType;

  MaskInput()
  {
    InitializeOutsideValue( static_cast<TOutput*>( NULL ) );
  }
  ~MaskInput() {}
  bool operator!=(const MaskInput &) const
  {
    return false;
  }

  bool operator==(const MaskInput & other) const
  {
    return !( *this != other );
  }

  inline TOutput operator()(const TInput & A, const TMask & B) const
  {
    if ( B != NumericTraits< TMask >::ZeroValue() )
      {
      return static_cast< TOutput >( A );
      }
    else
      {
      return m_OutsideValue;
      }
  }

  void SetOutsideValue(const TOutput & outsideValue)
  {
    m_OutsideValue = outsideValue;
  }

  const TOutput & GetOutsideValue() const
  {
    return m_OutsideValue;
  }

private:

  template < class TPixelType >
  void InitializeOutsideValue( TPixelType * )
  {
    this->m_OutsideValue = NumericTraits< TPixelType >::Zero;
  }

  template < class TValueType >
  void InitializeOutsideValue( VariableLengthVector<TValueType> * )
  {
    // set the outside value to be of zero length
    this->m_OutsideValue = VariableLengthVector< TValueType >(0);
  }

  TOutput m_OutsideValue;
};
}
template< class TInputImage, class TMaskImage, class TOutputImage = TInputImage >
class ITK_EXPORT MaskImageFilter:
  public
  BinaryFunctorImageFilter< TInputImage, TMaskImage, TOutputImage,
                            Functor::MaskInput<
                              typename TInputImage::PixelType,
                              typename TMaskImage::PixelType,
                              typename TOutputImage::PixelType >   >

{
public:
  typedef MaskImageFilter Self;
  typedef BinaryFunctorImageFilter< TInputImage, TMaskImage, TOutputImage,
                                    Functor::MaskInput<
                                      typename TInputImage::PixelType,
                                      typename TMaskImage::PixelType,
                                      typename TOutputImage::PixelType >
                                    >                                 Superclass;

  typedef SmartPointer< Self >       Pointer;
  typedef SmartPointer< const Self > ConstPointer;

  itkNewMacro(Self);

  itkTypeMacro(MaskImageFilter,
               BinaryFunctorImageFilter);

  typedef TMaskImage MaskImageType;

  void SetMaskImage(const MaskImageType *maskImage)
  {
    // Process object is not const-correct so the const casting is required.
    this->SetNthInput( 1, const_cast< MaskImageType * >( maskImage ) );
  }
  const MaskImageType * GetMaskImage()
  {
    return static_cast<const MaskImageType*>(this->ProcessObject::GetInput(1));
  }

  void SetOutsideValue(const typename TOutputImage::PixelType & outsideValue)
  {
    if ( this->GetOutsideValue() != outsideValue )
      {
      this->Modified();
      this->GetFunctor().SetOutsideValue(outsideValue);
      }
  }

  const typename TOutputImage::PixelType & GetOutsideValue() const
  {
    return this->GetFunctor().GetOutsideValue();
  }

  void BeforeThreadedGenerateData()
  {
    typedef typename TOutputImage::PixelType PixelType;
    this->CheckOutsideValue( static_cast<PixelType*>(NULL) );
  }

#ifdef ITK_USE_CONCEPT_CHECKING

  itkConceptMacro( MaskEqualityComparableCheck,
                   ( Concept::EqualityComparable< typename TMaskImage::PixelType > ) );
  itkConceptMacro( InputConvertibleToOutputCheck,
                   ( Concept::Convertible< typename TInputImage::PixelType,
                                           typename TOutputImage::PixelType > ) );

#endif
protected:
  MaskImageFilter() {}
  virtual ~MaskImageFilter() {}

  void PrintSelf(std::ostream & os, Indent indent) const
  {
    Superclass::PrintSelf(os, indent);
    os << indent << "OutsideValue: "  << this->GetOutsideValue() << std::endl;
  }

private:
  MaskImageFilter(const Self &); //purposely not implemented
  void operator=(const Self &);  //purposely not implemented

  template < class TPixelType >
  void CheckOutsideValue( const TPixelType * ) {}

  template < class TValue >
  void CheckOutsideValue( const VariableLengthVector< TValue > * )
  {
    // Check to see if the outside value contains only zeros. If so,
    // resize it to have the same number of zeros as the output
    // image. Otherwise, check that the number of components in the
    // outside value is the same as the number of components in the
    // output image. If not, throw an exception.
    VariableLengthVector< TValue > currentValue =
      this->GetFunctor().GetOutsideValue();
    VariableLengthVector< TValue > zeroVector( currentValue.GetSize() );
    zeroVector.Fill( NumericTraits< TValue >::Zero );

    if ( currentValue == zeroVector )
      {
      zeroVector.SetSize( this->GetOutput()->GetVectorLength() );
      zeroVector.Fill( NumericTraits< TValue >::Zero );
      this->GetFunctor().SetOutsideValue( zeroVector );
      }
    else if ( this->GetFunctor().GetOutsideValue().GetSize() !=
              this->GetOutput()->GetVectorLength() )
      {
      itkExceptionMacro(
        << "Number of components in OutsideValue: "
        <<  this->GetFunctor().GetOutsideValue().GetSize()
        << " is not the same as the "
        << "number of components in the image: "
        << this->GetOutput()->GetVectorLength());
      }
  }

};
} // end namespace itk

#endif