libinsighttoolkit3-dev 3.20.1+git20120521-6build1 / usr / include / InsightToolkit / Review / itkOptImageToImageMetric.h

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

  Program:   Insight Segmentation & Registration Toolkit
  Module:    itkOptImageToImageMetric.h
  Language:  C++
  Date:      $Date$
  Version:   $Revision$

  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 __itkOptImageToImageMetric_h
#define __itkOptImageToImageMetric_h

#include "itkSingleValuedCostFunction.h"
#include "itkImageBase.h"
#include "itkTransform.h"
#include "itkInterpolateImageFunction.h"
#include "itkExceptionObject.h"
#include "itkGradientRecursiveGaussianImageFilter.h"
#include "itkSpatialObject.h"
#include "itkBSplineDeformableTransform.h"
#include "itkCentralDifferenceImageFunction.h"
#include "itkCovariantVector.h"

#include "itkMultiThreader.h"

#include "itkOptBSplineInterpolateImageFunction.h"

namespace itk
{
  
/** \class ImageToImageMetric
 * \brief Computes similarity between regions of two images.
 *
 * This Class is templated over the type of the two input images.
 * It expects a Transform and an Interpolator to be plugged in.
 * This particular class is the base class for a hierarchy of 
 * similarity metrics.
 *
 * This class computes a value that measures the similarity 
 * between the Fixed image and the transformed Moving image.
 * The Interpolator is used to compute intensity values on 
 * non-grid positions resulting from mapping points through 
 * the Transform.
 * 
 *
 * \ingroup RegistrationMetrics
 *
 */

template <class TFixedImage,  class TMovingImage> 
class ITK_EXPORT ImageToImageMetric 
: public SingleValuedCostFunction 
{
public:
  /** Standard class typedefs. */
  typedef ImageToImageMetric           Self;
  typedef SingleValuedCostFunction     Superclass;
  typedef SmartPointer<Self>           Pointer;
  typedef SmartPointer<const Self>     ConstPointer;

  /** Type used for representing point components  */
  typedef typename Superclass::ParametersValueType CoordinateRepresentationType;

  /** Run-time type information (and related methods). */
  itkTypeMacro(ImageToImageMetric, SingleValuedCostFunction);

  /**  Type of the moving Image. */
  typedef TMovingImage                               MovingImageType;
  typedef typename TMovingImage::PixelType           MovingImagePixelType;
  typedef typename MovingImageType::ConstPointer     MovingImageConstPointer;

  /**  Type of the fixed Image. */
  typedef TFixedImage                                FixedImageType;
  typedef typename TFixedImage::PixelType            FixedImagePixelType;
  typedef typename FixedImageType::ConstPointer      FixedImageConstPointer;
  typedef typename FixedImageType::RegionType        FixedImageRegionType;

  /** Constants for the image dimensions */
  itkStaticConstMacro(MovingImageDimension, 
                      unsigned int,
                      TMovingImage::ImageDimension);
  itkStaticConstMacro(FixedImageDimension, 
                      unsigned int,
                      TFixedImage::ImageDimension);
  
  /**  Type of the Transform Base class */
  typedef Transform<CoordinateRepresentationType, 
                    itkGetStaticConstMacro(MovingImageDimension),
                    itkGetStaticConstMacro(FixedImageDimension)> 
                                                     TransformType;

  typedef typename TransformType::Pointer            TransformPointer;
  typedef typename TransformType::InputPointType     InputPointType;
  typedef typename TransformType::OutputPointType    OutputPointType;
  typedef typename TransformType::ParametersType     TransformParametersType;
  typedef typename TransformType::JacobianType       TransformJacobianType;

    /** Index and Point typedef support. */
  typedef typename FixedImageType::IndexType           FixedImageIndexType;
  typedef typename FixedImageIndexType::IndexValueType FixedImageIndexValueType;
  typedef typename MovingImageType::IndexType          MovingImageIndexType;
  typedef typename TransformType::InputPointType       FixedImagePointType;
  typedef typename TransformType::OutputPointType      MovingImagePointType;

  typedef std::vector<FixedImageIndexType>             FixedImageIndexContainer;

  /**  Type of the Interpolator Base class */
  typedef InterpolateImageFunction< MovingImageType, 
                                    CoordinateRepresentationType >
                                                     InterpolatorType;

  /** Gaussian filter to compute the gradient of the Moving Image */
  typedef typename NumericTraits<MovingImagePixelType>::RealType 
                                                     RealType;
  typedef CovariantVector<RealType,
                          itkGetStaticConstMacro(MovingImageDimension)>
                                                     GradientPixelType;
  typedef Image<GradientPixelType,
                itkGetStaticConstMacro(MovingImageDimension)> 
                                                     GradientImageType;
  typedef SmartPointer<GradientImageType>            GradientImagePointer;
  typedef GradientRecursiveGaussianImageFilter< MovingImageType,
                                                GradientImageType >
                                                     GradientImageFilterType;  
  typedef typename GradientImageFilterType::Pointer  GradientImageFilterPointer;


  typedef typename InterpolatorType::Pointer         InterpolatorPointer;


  /**  Type for the mask of the fixed image. Only pixels that are "inside"
       this mask will be considered for the computation of the metric */
  typedef SpatialObject< itkGetStaticConstMacro(FixedImageDimension) >
                                                     FixedImageMaskType;
  typedef typename FixedImageMaskType::Pointer       FixedImageMaskPointer;
  typedef typename FixedImageMaskType::ConstPointer  FixedImageMaskConstPointer;

  /**  Type for the mask of the moving image. Only pixels that are "inside"
       this mask will be considered for the computation of the metric */
  typedef SpatialObject< itkGetStaticConstMacro(MovingImageDimension) >
                                                     MovingImageMaskType;
  typedef typename MovingImageMaskType::Pointer      MovingImageMaskPointer;
  typedef typename MovingImageMaskType::ConstPointer MovingImageMaskConstPointer;


  /**  Type of the measure. */
  typedef typename Superclass::MeasureType                    MeasureType;

  /**  Type of the derivative. */
  typedef typename Superclass::DerivativeType                 DerivativeType;

  /**  Type of the parameters. */
  typedef typename Superclass::ParametersType                 ParametersType;

  /** Connect the Fixed Image.  */
  itkSetConstObjectMacro( FixedImage, FixedImageType );

  /** Get the Fixed Image. */
  itkGetConstObjectMacro( FixedImage, FixedImageType );

  /** Connect the Moving Image.  */
  itkSetConstObjectMacro( MovingImage, MovingImageType );

  /** Get the Moving Image. */
  itkGetConstObjectMacro( MovingImage, MovingImageType );

  /** Connect the Transform. */
  itkSetObjectMacro( Transform, TransformType );

  /** Get a pointer to the Transform.  */
  itkGetConstObjectMacro( Transform, TransformType );
 
  /** Connect the Interpolator. */
  itkSetObjectMacro( Interpolator, InterpolatorType );

  /** Get a pointer to the Interpolator.  */
  itkGetConstObjectMacro( Interpolator, InterpolatorType );

  /** Get the number of pixels considered in the computation. */
  unsigned long GetNumberOfMovingImageSamples( void )
    {
    return this->GetNumberOfPixelsCounted();
    }
  itkGetConstReferenceMacro( NumberOfPixelsCounted, unsigned long );

  /** Set the region over which the metric will be computed */
  void SetFixedImageRegion( const FixedImageRegionType reg );

  /** Get the region over which the metric will be computed */
  itkGetConstReferenceMacro( FixedImageRegion, FixedImageRegionType );
 
  /** Set/Get the moving image mask. */
  itkSetObjectMacro( MovingImageMask, MovingImageMaskType );
  itkSetConstObjectMacro( MovingImageMask, MovingImageMaskType );
  itkGetConstObjectMacro( MovingImageMask, MovingImageMaskType );

  /** Set/Get the fixed image mask. */
  itkSetObjectMacro( FixedImageMask, FixedImageMaskType );
  itkSetConstObjectMacro( FixedImageMask, FixedImageMaskType );
  itkGetConstObjectMacro( FixedImageMask, FixedImageMaskType );

  /** Set the fixed image indexes to be used as the samples when
   *   computing the match metric */
  void SetFixedImageIndexes( const FixedImageIndexContainer & indexes );
  void SetUseFixedImageIndexes( bool useIndex );
  itkGetConstReferenceMacro( UseFixedImageIndexes, bool );

  /** Set/Get number of threads to use for computations. */
  void SetNumberOfThreads( unsigned int numberOfThreads );
  itkGetConstReferenceMacro( NumberOfThreads, unsigned int );

  /** Set/Get gradient computation. */
  itkSetMacro( ComputeGradient, bool );
  itkGetConstReferenceMacro( ComputeGradient, bool );
  itkBooleanMacro(ComputeGradient );

  /** Computes the gradient image and assigns it to m_GradientImage */
  virtual void ComputeGradient( void );

  /** Get Gradient Image. */
  itkGetConstObjectMacro( GradientImage, GradientImageType );

  /** Set the parameters defining the Transform. */
  void SetTransformParameters( const ParametersType & parameters ) const;

  /** Return the number of parameters required by the Transform */
  unsigned int GetNumberOfParameters( void ) const 
    {
    return m_Transform->GetNumberOfParameters(); 
    }

  /** Initialize the Metric by making sure that all the components
   *  are present and plugged together correctly     */
  virtual void Initialize( void ) throw ( ExceptionObject );

  /** Initialize the components related to supporting multiple threads */
  virtual void MultiThreadingInitialize( void ) throw ( ExceptionObject );

  /** Number of spatial samples to used to compute metric 
   *   This sets the number of samples.  */
  virtual void SetNumberOfFixedImageSamples( unsigned long numSamples );
  itkGetConstReferenceMacro( NumberOfFixedImageSamples, unsigned long ); 

  /** Number of spatial samples to used to compute metric 
   *   This sets the number of samples.  */
  void SetNumberOfSpatialSamples( unsigned long num )
    {
    this->SetNumberOfFixedImageSamples( num ); 
    }
  unsigned long GetNumberOfSpatialSamples( void )
    {
    return this->GetNumberOfFixedImageSamples(); 
    }

  /** Minimum fixed-image intensity needed for a sample to be used in the
   *  metric computation */
  void SetFixedImageSamplesIntensityThreshold( const FixedImagePixelType & thresh );
  itkGetConstReferenceMacro( FixedImageSamplesIntensityThreshold, FixedImagePixelType );

  void SetUseFixedImageSamplesIntensityThreshold( bool useThresh );
  itkGetConstReferenceMacro( UseFixedImageSamplesIntensityThreshold, bool );

  /** Select whether the metric will be computed using all the pixels on the
   * fixed image region, or only using a set of randomly selected pixels. 
   * This value override IntensityThreshold, Masks, and SequentialSampling. */
  void SetUseAllPixels( bool useAllPixels );
  void UseAllPixelsOn( void )
    {
    this->SetUseAllPixels( true );
    }
  void UseAllPixelsOff( void )
    {
    this->SetUseAllPixels( false );
    }
  itkGetConstReferenceMacro( UseAllPixels, bool );

  /** If set to true, then every pixel in the fixed image will be scanned to
   * determine if it should be used in registration metric computation.  A
   * pixel will be chosen if it meets any mask or threshold limits set.  If
   * set to false, then UseAllPixels will be set to false. */
  void SetUseSequentialSampling( bool sequentialSampling );
  itkGetConstReferenceMacro( UseSequentialSampling, bool );

  /** Reinitialize the seed of the random number generator that selects the
   * sample of pixels used for estimating the image histograms and the joint
   * histogram. By nature, this metric is not deterministic, since at each run
   * it may select a different set of pixels. By initializing the random number
   * generator seed to the same value you can restore determinism. On the other
   * hand, calling the method ReinitializeSeed() without arguments will use the
   * clock from your machine in order to have a very random initialization of
   * the seed. This will indeed increase the non-deterministic behavior of the
   * metric. */
  void ReinitializeSeed();
  void ReinitializeSeed( int seed );  

  /** This boolean flag is only relevant when this metric is used along
   * with a BSplineDeformableTransform. The flag enables/disables the
   * caching of values computed when a physical point is mapped through
   * the BSplineDeformableTransform. In particular it will cache the
   * values of the BSpline weights for that points, and the indexes
   * indicating what BSpline-grid nodes are relevant for that specific
   * point. This caching is made optional due to the fact that the
   * memory arrays used for the caching can reach large sizes even for
   * moderate image size problems. For example, for a 3D image of
   * 256^3, using 20% of pixels, these arrays will take about 1
   * Gigabyte of RAM for storage. The ratio of computing time between
   * using the cache or not using the cache can reach 1:5, meaning that
   * using the caching can provide a five times speed up. It is
   * therefore, interesting to enable the caching, if enough memory is
   * available for it. The caching is enabled by default, in order to
   * preserve backward compatibility with previous versions of ITK. */
  itkSetMacro(UseCachingOfBSplineWeights,bool);
  itkGetConstReferenceMacro(UseCachingOfBSplineWeights,bool);
  itkBooleanMacro(UseCachingOfBSplineWeights);
      
  typedef MultiThreader               MultiThreaderType;
  /** Get the Threader. */
  itkGetConstObjectMacro( Threader, MultiThreaderType );
  const TransformPointer* GetThreaderTransform()
    {
    return m_ThreaderTransform;
    }

protected:
  ImageToImageMetric();
  virtual ~ImageToImageMetric();

  void PrintSelf(std::ostream& os, Indent indent) const;

  /** \class FixedImageSamplePoint 
   * A fixed image spatial sample consists of the fixed domain point 
   * and the fixed image value at that point. */
  /// @cond 
  class FixedImageSamplePoint
    {
    public:
    FixedImageSamplePoint()
      { 
      point.Fill(0.0);
      value = 0;
      valueIndex = 0;
      }
    ~FixedImageSamplePoint() {};

    public:
      FixedImagePointType           point;
      double                        value;
      unsigned int                  valueIndex;
    };
  /// @endcond 
  
  bool                      m_UseFixedImageIndexes;
  FixedImageIndexContainer  m_FixedImageIndexes;

  bool                      m_UseFixedImageSamplesIntensityThreshold;
  FixedImagePixelType       m_FixedImageSamplesIntensityThreshold;

  /** FixedImageSamplePoint typedef support. */
  typedef std::vector<FixedImageSamplePoint> FixedImageSampleContainer;

  /** Uniformly select a sample set from the fixed image domain. */
  virtual void SampleFixedImageRegion( FixedImageSampleContainer & samples) const;

  virtual void SampleFixedImageIndexes( FixedImageSampleContainer & 
                                           samples) const;

  /** Gather all the pixels from the fixed image domain. */
  virtual void SampleFullFixedImageRegion( FixedImageSampleContainer & 
                                           samples) const;

  /** Container to store a set of points and fixed image values. */
  FixedImageSampleContainer   m_FixedImageSamples;

  unsigned long               m_NumberOfParameters;
  mutable ParametersType      m_Parameters;

  unsigned long               m_NumberOfFixedImageSamples;
  //m_NumberOfPixelsCounted must be mutable because the const
  //thread consolidation functions merge each threads valus
  //onto this accumulator variable.
  mutable unsigned long       m_NumberOfPixelsCounted;

  FixedImageConstPointer      m_FixedImage;
  MovingImageConstPointer     m_MovingImage;

  /** Main transform to be used in thread = 0 */
  TransformPointer            m_Transform;
  /** Copies of Transform helpers per thread (N-1 of them, since m_Transform
   * will do the work for thread=0. */
  TransformPointer          * m_ThreaderTransform; 

  InterpolatorPointer         m_Interpolator;

  bool                        m_ComputeGradient;
  GradientImagePointer        m_GradientImage;

  FixedImageMaskConstPointer  m_FixedImageMask;
  MovingImageMaskConstPointer m_MovingImageMask;

  unsigned int                m_NumberOfThreads;

  bool                        m_UseAllPixels;
  bool                        m_UseSequentialSampling;

  bool                        m_ReseedIterator;

  int                         m_RandomSeed;

 /** Types and variables related to BSpline deformable transforms.
   * If the transform is of type third order BSplineDeformableTransform,
   * then we can speed up the metric derivative calculation by
   * only inspecting the parameters within the support region
   * of a mapped point.  */

  /** Boolean to indicate if the transform is BSpline deformable. */
  bool                        m_TransformIsBSpline;

  /** The number of BSpline transform weights is the number of
    * of parameter in the support region (per dimension ). */   
  unsigned long               m_NumBSplineWeights;

  itkStaticConstMacro(DeformationSplineOrder, unsigned int, 3 );

  typedef BSplineDeformableTransform< CoordinateRepresentationType,
                      ::itk::GetImageDimension<FixedImageType>::ImageDimension,
                                      itkGetStaticConstMacro(DeformationSplineOrder) >             BSplineTransformType;

  typedef typename BSplineTransformType::WeightsType       BSplineTransformWeightsType;
  typedef typename BSplineTransformWeightsType::ValueType  WeightsValueType;
  typedef          Array2D<WeightsValueType>               BSplineTransformWeightsArrayType;

  typedef typename BSplineTransformType::ParameterIndexArrayType 
                                                              BSplineTransformIndexArrayType;
  typedef typename BSplineTransformIndexArrayType::ValueType  IndexValueType;
  typedef          Array2D<IndexValueType>                    BSplineTransformIndicesArrayType;

  typedef          std::vector<MovingImagePointType>          MovingImagePointArrayType;
  typedef          std::vector<bool>                          BooleanArrayType;
  typedef          FixedArray< unsigned long, 
                               ::itk::GetImageDimension<FixedImageType>
                                ::ImageDimension >            BSplineParametersOffsetType;
  /**
   * If a BSplineInterpolationFunction is used, this class obtain
   * image derivatives from the BSpline interpolator. Otherwise, 
   * image derivatives are computed using central differencing.
   */
  typedef BSplineInterpolateImageFunction<MovingImageType,
                                             CoordinateRepresentationType> 
                                                       BSplineInterpolatorType;
  /** Typedefs for using central difference calculator. */
  typedef CentralDifferenceImageFunction<MovingImageType,
                                         CoordinateRepresentationType> 
                                                       DerivativeFunctionType;
  typedef          CovariantVector< double,
                           itkGetStaticConstMacro(MovingImageDimension) >
                                                          ImageDerivativesType;


  typename BSplineTransformType::Pointer   m_BSplineTransform;

  BSplineTransformWeightsArrayType         m_BSplineTransformWeightsArray;
  BSplineTransformIndicesArrayType         m_BSplineTransformIndicesArray;
  MovingImagePointArrayType                m_BSplinePreTransformPointsArray;
  BooleanArrayType                         m_WithinBSplineSupportRegionArray;
  
  BSplineParametersOffsetType              m_BSplineParametersOffset;

  // Variables needed for optionally caching values when using a BSpline transform.
  bool                                    m_UseCachingOfBSplineWeights;
  mutable BSplineTransformWeightsType     m_BSplineTransformWeights;
  mutable BSplineTransformIndexArrayType  m_BSplineTransformIndices;

  mutable BSplineTransformWeightsType     * m_ThreaderBSplineTransformWeights;
  mutable BSplineTransformIndexArrayType  * m_ThreaderBSplineTransformIndices;

  virtual void PreComputeTransformValues( void );

  /** Transform a point from FixedImage domain to MovingImage domain.
   * This function also checks if mapped point is within support region. */
  virtual void TransformPoint( unsigned int sampleNumber,
                               MovingImagePointType& mappedPoint,
                               bool& sampleWithinSupportRegion,
                               double& movingImageValue,
                               unsigned int threadID ) const;

  virtual void TransformPointWithDerivatives( unsigned int sampleNumber,
                               MovingImagePointType& mappedPoint,
                               bool& sampleWithinSupportRegion,
                               double& movingImageValue,
                               ImageDerivativesType & gradient,
                               unsigned int threadID ) const;

  /** Boolean to indicate if the interpolator BSpline. */
  bool                                       m_InterpolatorIsBSpline;
  /** Pointer to BSplineInterpolator. */
  typename BSplineInterpolatorType::Pointer  m_BSplineInterpolator;

  /** Pointer to central difference calculator. */
  typename DerivativeFunctionType::Pointer   m_DerivativeCalculator;

  /** Compute image derivatives at a point. */
  virtual void ComputeImageDerivatives( const MovingImagePointType & mappedPoint,
                                        ImageDerivativesType & gradient,
                                        unsigned int threadID ) const;


  /**
   * Types and variables related to multi-threading
   */

  struct MultiThreaderParameterType
    {
    ImageToImageMetric                   * metric;
    };

  MultiThreaderType::Pointer               m_Threader;
  MultiThreaderParameterType               m_ThreaderParameter;
  mutable unsigned int                   * m_ThreaderNumberOfMovingImageSamples;
  bool                                     m_WithinThreadPreProcess;
  bool                                     m_WithinThreadPostProcess;

  void                           GetValueMultiThreadedPreProcessInitiate( void ) const;
  void                           GetValueMultiThreadedInitiate( void ) const;
  void                           GetValueMultiThreadedPostProcessInitiate( void ) const;
  static ITK_THREAD_RETURN_TYPE  GetValueMultiThreadedPreProcess( void * arg );
  static ITK_THREAD_RETURN_TYPE  GetValueMultiThreaded( void * arg );
  static ITK_THREAD_RETURN_TYPE  GetValueMultiThreadedPostProcess( void * arg );

  virtual inline void       GetValueThread( unsigned int threadID ) const;
  virtual inline void       GetValueThreadPreProcess( 
                                 unsigned int itkNotUsed(threadID),
                                 bool itkNotUsed(withinSampleThread) ) const
    { };
  virtual inline bool       GetValueThreadProcessSample( 
                                 unsigned int itkNotUsed(threadID),
                                 unsigned long itkNotUsed(fixedImageSample),
                                 const MovingImagePointType & itkNotUsed(mappedPoint),
                                 double itkNotUsed(movingImageValue)) const
    { return false; };
  virtual inline void       GetValueThreadPostProcess( 
                                 unsigned int itkNotUsed(threadID),
                                 bool itkNotUsed(withinSampleThread) ) const
    { };
      
  void                          GetValueAndDerivativeMultiThreadedPreProcessInitiate( void ) const;
  void                          GetValueAndDerivativeMultiThreadedInitiate( void ) const;
  void                          GetValueAndDerivativeMultiThreadedPostProcessInitiate( void ) const;
  static ITK_THREAD_RETURN_TYPE GetValueAndDerivativeMultiThreadedPreProcess( void * arg );
  static ITK_THREAD_RETURN_TYPE GetValueAndDerivativeMultiThreaded(void * arg);
  static ITK_THREAD_RETURN_TYPE GetValueAndDerivativeMultiThreadedPostProcess(void * arg);

  virtual inline void  GetValueAndDerivativeThread(unsigned int threadID) const;
  virtual inline void  GetValueAndDerivativeThreadPreProcess(
                                unsigned int itkNotUsed(threadID),
                                bool itkNotUsed(withinSampleThread)) const 
    { };
  virtual inline bool  GetValueAndDerivativeThreadProcessSample( 
                                unsigned int itkNotUsed(threadID),
                                unsigned long itkNotUsed(fixedImageSample),
                                const MovingImagePointType & itkNotUsed(mappedPoint),
                                double itkNotUsed(movingImageValue),
                                const ImageDerivativesType & itkNotUsed(movingImageGradientValue) ) const
    { return false; }
  virtual inline void  GetValueAndDerivativeThreadPostProcess( 
                                unsigned int itkNotUsed(threadID),
                                bool itkNotUsed(withinSampleThread) ) const 
    { };

  /** Synchronizes the threader transforms with the transform
   *   member variable.
   */
  virtual void SynchronizeTransforms() const;

private:
  ImageToImageMetric(const Self&); //purposely not implemented
  void operator=(const Self&); //purposely not implemented
  
  FixedImageRegionType        m_FixedImageRegion;  

};

} // end namespace itk

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

#endif