// This line can be removed once the optimized versions
// gets integrated into the main directories.
#include "itkConfigure.h"
-
-#ifdef ITK_USE_OPTIMIZED_REGISTRATION_METHODS
#include "itkOptMattesMutualInformationImageToImageMetricFor3DBLUTFFD.h"
-#else
-
-#include "itkImageToImageMetric.h"
-#include "itkCovariantVector.h"
-#include "itkPoint.h"
-#include "itkIndex.h"
-#include "itkBSplineKernelFunction.h"
-#include "itkBSplineDerivativeKernelFunction.h"
-#include "itkCentralDifferenceImageFunction.h"
-#include "itkBSplineInterpolateImageFunction.h"
-#include "itkBSplineDeformableTransform.h"
-#include "itkArray2D.h"
-
-namespace itk
-{
-
-/** \class MattesMutualInformationImageToImageMetricFor3DBLUTFFD
- * \brief Computes the mutual information between two images to be
- * registered using the method of Mattes et al.
- *
- * MattesMutualInformationImageToImageMetricFor3DBLUTFFD computes the mutual
- * information between a fixed and moving image to be registered.
- *
- * This class is templated over the FixedImage type and the MovingImage
- * type.
- *
- * The fixed and moving images are set via methods SetFixedImage() and
- * SetMovingImage(). This metric makes use of user specified Transform and
- * Interpolator. The Transform is used to map points from the fixed image to
- * the moving image domain. The Interpolator is used to evaluate the image
- * intensity at user specified geometric points in the moving image.
- * The Transform and Interpolator are set via methods SetTransform() and
- * SetInterpolator().
- *
- * If a BSplineInterpolationFunction is used, this class obtain
- * image derivatives from the BSpline interpolator. Otherwise,
- * image derivatives are computed using central differencing.
- *
- * \warning This metric assumes that the moving image has already been
- * connected to the interpolator outside of this class.
- *
- * The method GetValue() computes of the mutual information
- * while method GetValueAndDerivative() computes
- * both the mutual information and its derivatives with respect to the
- * transform parameters.
- *
- * The calculations are based on the method of Mattes et al [1,2]
- * where the probability density distribution are estimated using
- * Parzen histograms. Since the fixed image PDF does not contribute
- * to the derivatives, it does not need to be smooth. Hence,
- * a zero order (box car) BSpline kernel is used
- * for the fixed image intensity PDF. On the other hand, to ensure
- * smoothness a third order BSpline kernel is used for the
- * moving image intensity PDF.
- *
- * On Initialize(), the FixedImage is uniformly sampled within
- * the FixedImageRegion. The number of samples used can be set
- * via SetNumberOfSpatialSamples(). Typically, the number of
- * spatial samples used should increase with the image size.
- *
- * The option UseAllPixelOn() disables the random sampling and uses
- * all the pixels of the FixedImageRegion in order to estimate the
- * joint intensity PDF.
- *
- * During each call of GetValue(), GetDerivatives(),
- * GetValueAndDerivatives(), marginal and joint intensity PDF's
- * values are estimated at discrete position or bins.
- * The number of bins used can be set via SetNumberOfHistogramBins().
- * To handle data with arbitray magnitude and dynamic range,
- * the image intensity is scale such that any contribution to the
- * histogram will fall into a valid bin.
- *
- * One the PDF's have been contructed, the mutual information
- * is obtained by doubling summing over the discrete PDF values.
- *
- *
- * Notes:
- * 1. This class returns the negative mutual information value.
- * 2. This class in not thread safe due the private data structures
- * used to the store the sampled points and the marginal and joint pdfs.
- *
- * References:
- * [1] "Nonrigid multimodality image registration"
- * D. Mattes, D. R. Haynor, H. Vesselle, T. Lewellen and W. Eubank
- * Medical Imaging 2001: Image Processing, 2001, pp. 1609-1620.
- * [2] "PET-CT Image Registration in the Chest Using Free-form Deformations"
- * D. Mattes, D. R. Haynor, H. Vesselle, T. Lewellen and W. Eubank
- * IEEE Transactions in Medical Imaging. Vol.22, No.1,
- January 2003. pp.120-128.
- * [3] "Optimization of Mutual Information for MultiResolution Image
- * Registration"
- * P. Thevenaz and M. Unser
- * IEEE Transactions in Image Processing, 9(12) December 2000.
- *
- * \ingroup RegistrationMetrics
- * \ingroup ThreadUnSafe
- */
-template <class TFixedImage,class TMovingImage >
-class ITK_EXPORT MattesMutualInformationImageToImageMetricFor3DBLUTFFD :
- public ImageToImageMetric< TFixedImage, TMovingImage >
-{
-public:
-
- /** Standard class typedefs. */
- typedef MattesMutualInformationImageToImageMetricFor3DBLUTFFD Self;
- typedef ImageToImageMetric< TFixedImage, TMovingImage > Superclass;
- typedef SmartPointer<Self> Pointer;
- typedef SmartPointer<const Self> ConstPointer;
-
- /** Method for creation through the object factory. */
- itkNewMacro(Self);
-
- /** Run-time type information (and related methods). */
- itkTypeMacro(MattesMutualInformationImageToImageMetricFor3DBLUTFFD, ImageToImageMetric);
-
- /** Types inherited from Superclass. */
- typedef typename Superclass::TransformType TransformType;
- typedef typename Superclass::TransformPointer TransformPointer;
- typedef typename Superclass::TransformJacobianType TransformJacobianType;
- typedef typename Superclass::InterpolatorType InterpolatorType;
- typedef typename Superclass::MeasureType MeasureType;
- typedef typename Superclass::DerivativeType DerivativeType;
- typedef typename Superclass::ParametersType ParametersType;
- typedef typename Superclass::FixedImageType FixedImageType;
- typedef typename Superclass::MovingImageType MovingImageType;
- typedef typename Superclass::FixedImageConstPointer FixedImageConstPointer;
- typedef typename Superclass::MovingImageConstPointer MovingImageCosntPointer;
- typedef typename Superclass::InputPointType InputPointType;
- typedef typename Superclass::OutputPointType OutputPointType;
-
- typedef typename Superclass::CoordinateRepresentationType
- CoordinateRepresentationType;
-
- /** 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;
-
- /** The moving image dimension. */
- itkStaticConstMacro( MovingImageDimension, unsigned int,
- MovingImageType::ImageDimension );
-
- /**
- * Initialize the Metric by
- * (1) making sure that all the components are present and plugged
- * together correctly,
- * (2) uniformly select NumberOfSpatialSamples within
- * the FixedImageRegion, and
- * (3) allocate memory for pdf data structures. */
- virtual void Initialize(void) throw ( ExceptionObject );
-
- /** Get the derivatives of the match measure. */
- void GetDerivative( const ParametersType& parameters,
- DerivativeType & Derivative ) const;
-
- /** Get the value. */
- MeasureType GetValue( const ParametersType& parameters ) const;
-
- /** Get the value and derivatives for single valued optimizers. */
- void GetValueAndDerivative( const ParametersType& parameters,
- MeasureType& Value,
- DerivativeType& Derivative ) const;
-
- /** Number of spatial samples to used to compute metric */
- itkSetClampMacro( NumberOfSpatialSamples, unsigned long,
- 1, NumericTraits<unsigned long>::max() );
- itkGetConstReferenceMacro( NumberOfSpatialSamples, unsigned long);
-
- /** Number of bins to used in the histogram. Typical value is 50. */
- itkSetClampMacro( NumberOfHistogramBins, unsigned long,
- 1, NumericTraits<unsigned long>::max() );
- itkGetConstReferenceMacro( NumberOfHistogramBins, unsigned long);
-
- /** 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);
-
- /** 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. */
- itkSetMacro(UseAllPixels,bool);
- itkGetConstReferenceMacro(UseAllPixels,bool);
- itkBooleanMacro(UseAllPixels);
-
- /** This variable selects the method to be used for computing the Metric
- * derivatives with respect to the Transform parameters. Two modes of
- * computation are available. The choice between one and the other is a
- * trade-off between computation speed and memory allocations. The two modes
- * are described in detail below:
- *
- * UseExplicitPDFDerivatives = True
- * will compute the Metric derivative by first calculating the derivatives of
- * each one of the Joint PDF bins with respect to each one of the Transform
- * parameters and then accumulating these contributions in the final metric
- * derivative array by using a bin-specific weight. The memory required for
- * storing the intermediate derivatives is a 3D array of doubles with size
- * equals to the product of (number of histogram bins)^2 times number of
- * transform parameters. This method is well suited for Transform with a small
- * number of parameters.
- *
- * UseExplicitPDFDerivatives = False will compute the Metric derivative by
- * first computing the weights for each one of the Joint PDF bins and caching
- * them into an array. Then it will revisit each one of the PDF bins for
- * computing its weighted contribution to the full derivative array. In this
- * method an extra 2D array is used for storing the weights of each one of
- * the PDF bins. This is an array of doubles with size equals to (number of
- * histogram bins)^2. This method is well suited for Transforms with a large
- * number of parameters, such as, BSplineDeformableTransforms. */
- itkSetMacro(UseExplicitPDFDerivatives,bool);
- itkGetConstReferenceMacro(UseExplicitPDFDerivatives,bool);
- itkBooleanMacro(UseExplicitPDFDerivatives);
-
- /** 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);
-
-protected:
-
- MattesMutualInformationImageToImageMetricFor3DBLUTFFD();
- virtual ~MattesMutualInformationImageToImageMetricFor3DBLUTFFD() {};
- void PrintSelf(std::ostream& os, Indent indent) const;
-
- /** \class FixedImageSpatialSample
- * A fixed image spatial sample consists of the fixed domain point
- * and the fixed image value at that point. */
- /// @cond
- class FixedImageSpatialSample
- {
- public:
- FixedImageSpatialSample():FixedImageValue(0.0) {
- FixedImagePointValue.Fill(0.0);
- }
- ~FixedImageSpatialSample() {};
-
- FixedImagePointType FixedImagePointValue;
- double FixedImageValue;
- unsigned int FixedImageParzenWindowIndex;
- };
- /// @endcond
-
- /** FixedImageSpatialSample typedef support. */
- typedef std::vector<FixedImageSpatialSample>
- FixedImageSpatialSampleContainer;
-
- /** Container to store a set of points and fixed image values. */
- FixedImageSpatialSampleContainer m_FixedImageSamples;
-
- /** Uniformly select a sample set from the fixed image domain. */
- virtual void SampleFixedImageDomain(
- FixedImageSpatialSampleContainer& samples);
-
- /** Gather all the pixels from the fixed image domain. */
- virtual void SampleFullFixedImageDomain(
- FixedImageSpatialSampleContainer& samples);
-
- /** 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,
- const ParametersType& parameters,
- MovingImagePointType& mappedPoint,
- bool& sampleWithinSupportRegion,
- double& movingImageValue ) const;
-
-private:
-
- //purposely not implemented
- MattesMutualInformationImageToImageMetricFor3DBLUTFFD(const Self&);
- //purposely not implemented
- void operator=(const Self&);
-
-
- /** The marginal PDFs are stored as std::vector. */
- typedef float PDFValueType;
- typedef std::vector<PDFValueType> MarginalPDFType;
-
- /** The fixed image marginal PDF. */
- mutable MarginalPDFType m_FixedImageMarginalPDF;
-
- /** The moving image marginal PDF. */
- mutable MarginalPDFType m_MovingImageMarginalPDF;
-
- /** Helper array for storing the values of the JointPDF ratios. */
- typedef double PRatioType;
- typedef Array2D< PRatioType > PRatioArrayType;
- mutable PRatioArrayType m_PRatioArray;
-
- /** Helper variable for accumulating the derivative of the metric. */
- mutable DerivativeType m_MetricDerivative;
-
- /** Typedef for the joint PDF and PDF derivatives are stored as ITK Images. */
- typedef Image<PDFValueType,2> JointPDFType;
- typedef JointPDFType::IndexType JointPDFIndexType;
- typedef JointPDFType::PixelType JointPDFValueType;
- typedef JointPDFType::RegionType JointPDFRegionType;
- typedef JointPDFType::SizeType JointPDFSizeType;
- typedef Image<PDFValueType,3> JointPDFDerivativesType;
- typedef JointPDFDerivativesType::IndexType JointPDFDerivativesIndexType;
- typedef JointPDFDerivativesType::PixelType JointPDFDerivativesValueType;
- typedef JointPDFDerivativesType::RegionType JointPDFDerivativesRegionType;
- typedef JointPDFDerivativesType::SizeType JointPDFDerivativesSizeType;
-
- /** The joint PDF and PDF derivatives. */
- typename JointPDFType::Pointer m_JointPDF;
- typename JointPDFDerivativesType::Pointer m_JointPDFDerivatives;
-
- unsigned long m_NumberOfSpatialSamples;
- unsigned long m_NumberOfParameters;
-
- /** Variables to define the marginal and joint histograms. */
- unsigned long m_NumberOfHistogramBins;
- double m_MovingImageNormalizedMin;
- double m_FixedImageNormalizedMin;
- double m_MovingImageTrueMin;
- double m_MovingImageTrueMax;
- double m_FixedImageBinSize;
- double m_MovingImageBinSize;
-
- /** Typedefs for BSpline kernel and derivative functions. */
- typedef BSplineKernelFunction<3> CubicBSplineFunctionType;
- typedef BSplineDerivativeKernelFunction<3> CubicBSplineDerivativeFunctionType;
-
- /** Cubic BSpline kernel for computing Parzen histograms. */
- typename CubicBSplineFunctionType::Pointer m_CubicBSplineKernel;
- typename CubicBSplineDerivativeFunctionType::Pointer
- m_CubicBSplineDerivativeKernel;
-
- /** Precompute fixed image parzen window indices. */
- virtual void ComputeFixedImageParzenWindowIndices(
- FixedImageSpatialSampleContainer& samples );
-
- /**
- * Types and variables related to image derivative calculations.
- * If a BSplineInterpolationFunction is used, this class obtain
- * image derivatives from the BSpline interpolator. Otherwise,
- * image derivatives are computed using central differencing.
- */
- typedef CovariantVector< double,
- itkGetStaticConstMacro(MovingImageDimension) >
- ImageDerivativesType;
-
- /** Compute image derivatives at a point. */
- virtual void ComputeImageDerivatives( const MovingImagePointType& mappedPoint,
- ImageDerivativesType& gradient ) const;
-
- /** Boolean to indicate if the interpolator BSpline. */
- bool m_InterpolatorIsBSpline;
-
- /** Typedefs for using BSpline interpolator. */
- typedef
- BSplineInterpolateImageFunction<MovingImageType,
- CoordinateRepresentationType>
- BSplineInterpolatorType;
-
- /** Pointer to BSplineInterpolator. */
- typename BSplineInterpolatorType::Pointer m_BSplineInterpolator;
-
- /** Typedefs for using central difference calculator. */
- typedef CentralDifferenceImageFunction<MovingImageType,
- CoordinateRepresentationType>
- DerivativeFunctionType;
-
- /** Pointer to central difference calculator. */
- typename DerivativeFunctionType::Pointer m_DerivativeCalculator;
-
-
- /** Compute PDF derivative contribution for each parameter. */
- virtual void ComputePDFDerivatives( unsigned int sampleNumber,
- int movingImageParzenWindowIndex,
- const ImageDerivativesType&
- movingImageGradientValue,
- double cubicBSplineDerivativeValue
- ) const;
-
- /**
- * 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 parameters per image dimension. */
- long m_NumParametersPerDim;
-
- /**
- * The number of BSpline transform weights is the number of
- * of parameter in the support region (per dimension ). */
- unsigned long m_NumBSplineWeights;
-
- /** The fixed image dimension. */
- itkStaticConstMacro( FixedImageDimension, unsigned int,
- FixedImageType::ImageDimension );
-
- /**
- * Enum of the deformabtion field spline order.
- */
- enum { DeformationSplineOrder = 3 };
-
- /**
- * Typedefs for the BSplineDeformableTransform.
- */
- typedef BSplineDeformableTransform<
- CoordinateRepresentationType,
- ::itk::GetImageDimension<FixedImageType>::ImageDimension,
- DeformationSplineOrder> BSplineTransformType;
- typedef typename BSplineTransformType::WeightsType
- BSplineTransformWeightsType;
- typedef typename BSplineTransformType::ParameterIndexArrayType
- BSplineTransformIndexArrayType;
-
- /**
- * Variables used when transform is of type BSpline deformable.
- */
- typename BSplineTransformType::Pointer m_BSplineTransform;
-
- /**
- * Cache pre-transformed points, weights, indices and
- * within support region flag.
- */
- typedef typename BSplineTransformWeightsType::ValueType WeightsValueType;
- typedef Array2D<WeightsValueType> BSplineTransformWeightsArrayType;
- typedef typename BSplineTransformIndexArrayType::ValueType IndexValueType;
- typedef Array2D<IndexValueType> BSplineTransformIndicesArrayType;
- typedef std::vector<MovingImagePointType> MovingImagePointArrayType;
- typedef std::vector<bool> BooleanArrayType;
-
- BSplineTransformWeightsArrayType m_BSplineTransformWeightsArray;
- BSplineTransformIndicesArrayType m_BSplineTransformIndicesArray;
- MovingImagePointArrayType m_PreTransformPointsArray;
- BooleanArrayType m_WithinSupportRegionArray;
-
- typedef FixedArray<unsigned long,
- ::itk::GetImageDimension<FixedImageType>::ImageDimension>
- ParametersOffsetType;
- ParametersOffsetType m_ParametersOffset;
-
- bool m_UseAllPixels;
-
- virtual void PreComputeTransformValues();
-
- bool m_ReseedIterator;
- int m_RandomSeed;
-
- // Selection of explicit or implicit computation of PDF derivatives
- // with respect to Transform parameters.
- bool m_UseExplicitPDFDerivatives;
-
- // Variables needed for optionally caching values when using a BSpline transform.
- bool m_UseCachingOfBSplineWeights;
- mutable BSplineTransformWeightsType m_Weights;
- mutable BSplineTransformIndexArrayType m_Indices;
-
-};
-
-} // end namespace itk
-
-#ifndef ITK_MANUAL_INSTANTIATION
-#include "itkMattesMutualInformationImageToImageMetricFor3DBLUTFFD.txx"
-#endif
-
-#endif
-
#endif