Class AlgorithmRegOAR2D

  • All Implemented Interfaces:
    java.awt.event.ActionListener, java.awt.event.WindowListener, java.lang.Runnable, java.util.EventListener

    public class AlgorithmRegOAR2D
    extends AlgorithmBase
    This is an automatic registration method based on FLIRT. FLIRT stands for FMRIB's Linear Image Registration Tool. For more information on FLIRT, visit their homepage at http://www.fmrib.ox.ac.uk/fsl/flirt/. Their main paper is:

    Jenkinson, M. and Smith, S. (2001a).
    A global optimisation method for robust affine registration of brain images.
    Medical Image Analysis, 5(2):143-156.

    Our algorithm works as follows:
    1.) We find the minimum resolution of the images and blur them if neccessary.
    2.) We transform the images into isotropic voxels.
    3.) We subsample the images by 2, 4, and 8, depending on the resolution.
    4.) With the images that were subsampled by 8, we call levelEight. This function will use the coarse sampling rate and optimize translations and global scale at the given rotation. So for example, if the coarse sampling range were -30 to 30 at every 15 degrees, we would optimize at rotations of -30, -15, 0, 15, 30.
    5.) Still in levelEight, we now measure the cost at the fine sampling rate. We interpolate the translations and global scale to come up with a good guess as to what the optimized translation would be at that point.
    6.) We take the top 20% of the points and optimize them.
    7.) We now have a large multi-array of costs. 20% of those have been optimized and placed back into their original position in the multi-array. We look at the 2 neighbors of a point: + and - one fine sample. If our point has a cost greater than any of these, it is not a minima. Otherwise it is. We save it in a vector of minima.
    8.) We optimize the minima over rotation as well as translations and global scale. (Previously we had not optimized over rotation.) We return two vectors, one containing the minima before optimization, one containing the minima after optimization.
    9.) We now call levelFour with the images subsampled by 4 and the vectors of minima. We measure the costs of the minima on the new images and sort them. We take the top numMinima in each vector (pre-optimization and post-optimization) and optimize them. We put them all into one vector.
    10.) We perturb the rotation by zero and plus-minus fineDelta. If it's not a rigid transformation, we then perturb the global scaling by factors of 0.8, 0.9, 1.0, 1.1, and 1.2.
    11.) We optimize the perturbations. We return a vector of the perturbed, optimized minima.
    12.) We now call levelTwo with the images subsampled by 2. We measure the costs of the minima at the new images. We optimize the best minimum with 4 degrees of freedom, then 5, then 6. If the user has limited the degrees of freedom to 3, there will only be one optimization run, with 3 degrees of freedom. The function returns the best minimum after optimization.
    13.) We call levelOne with the un-subsampled images. At levelOne, one optimization run is performed, with the maximum allowable degrees of freedom, as specified by the user (the max is 6).
    14.) The best answer is returned from levelOne. The matrix from this answer is saved in a file and also accessed by the dialog that called this algorithm.

    Note that when 6 degrees of freedom is used the rotation is set equal to 0 because diffX sets (0,2), diffY sets (1,2), scaleX sets (0,0), scaleY sets (1,1), skewX sets (0,1), and skewY sets (1,0) so all 6 elements are set.

    Author:
    Neva Cherniavsky, Matthew McAuliffe
    • Field Detail

      • allowLevel16

        private boolean allowLevel16
        DOCUMENT ME!
      • allowLevel2

        private boolean allowLevel2
        DOCUMENT ME!
      • allowLevel4

        private boolean allowLevel4
        DOCUMENT ME!
      • allowLevel8

        private boolean allowLevel8
        DOCUMENT ME!
      • answer

        private MatrixListItem answer
        Final answer after registration.
      • baseNumIter

        private int baseNumIter
        these numbers hard coded for constructors that don't include them.
      • blurredInput

        private ModelImage blurredInput
        Blurred input image.
      • blurredRef

        private ModelImage blurredRef
        Blurred reference image.
      • coarseNum

        private final int coarseNum
        Number of passes that will be made in the coarse sampling and fine sampling.
      • fineNum

        private final int fineNum
        Number of passes that will be made in the coarse sampling and fine sampling.
      • costChoice

        private int costChoice
        Choice of which cost function to use.
      • doColor

        private boolean doColor
        DOCUMENT ME!
      • DOF

        private int DOF
        Maximum degrees of freedom when running the optimization.
      • doSubsample

        private final boolean doSubsample
        If true subsample.
      • doJTEM

        private boolean doJTEM
      • doMultiThread

        private boolean doMultiThread
      • imageInputIso

        private ModelImage imageInputIso
        Isotropic input image.
      • imageRefIso

        private ModelImage imageRefIso
        Isotropic reference image.
      • imageWeightInputIso

        private ModelImage imageWeightInputIso
        Isotropic weighted input image.
      • imageWeightRefIso

        private ModelImage imageWeightRefIso
        Isotropic weighted reference image.
      • inputImage

        private ModelImage inputImage
        This image is to registered to the reference image.
      • inputWeight

        private ModelImage inputWeight
        This gives weights for the input image - higher weights mean a greater impact in that area on the registration.
      • interp

        private final int interp
        Interpolation method.
      • level1Factor

        private float level1Factor
        Multiplication factor for level 1 - will be set based on subsampling.
      • level2Factor

        private float level2Factor
        Multiplication factor for level 2 - will be set based on subsampling.
      • level4Factor

        private float level4Factor
        Multiplication factor for level 4 - will be set based on subsampling.
      • m_bBruteForce

        private boolean m_bBruteForce
        If true, calculate the brute-force solution:.
      • m_fRotationRange

        private float m_fRotationRange
        The range of rotations to try in brute-force mode:.
      • m_fXScaleRange

        private float m_fXScaleRange
        The range of scales in x to try in brute-force mode:.
      • m_fYScaleRange

        private float m_fYScaleRange
        The range of scales in y to try in brute-force mode:.
      • m_iScaleSteps

        private int m_iScaleSteps
        The number of steps to divide scale ranges:.
      • m_iTranslationRange

        private int m_iTranslationRange
        The range of x,y translations to try in brute-force mode:.
      • maxDim

        private int maxDim
        DOCUMENT ME!
      • maxIter

        private int maxIter
        Limits number of iterations in Powell optimization. maxIter in the call to Powell's will be an integer multiple of baseNumIter
      • numMinima

        private int numMinima
        Number of minima from level 8 to test at level 4.
      • refImage

        private ModelImage refImage
        The inputImage will be registered to this reference image.
      • refWeight

        private ModelImage refWeight
        This gives weights for the reference image - higher weights mean a greater impact in that area on the registration.
      • resampleInput

        private boolean resampleInput
        DOCUMENT ME!
      • resampleRef

        private boolean resampleRef
        DOCUMENT ME!
      • resInput

        private final float[] resInput
        The voxel resolutions of the image to be registered to the reference image.
      • resRef

        private final float[] resRef
        The voxel resolutions of the reference image.
      • rigidFlag

        private boolean rigidFlag
        Flag used to indicate if the registration is rigid (rotation and translation only; DOF = 3.
      • rotateBegin

        private final float rotateBegin
        Coarse and fine sampling parameters.
      • rotateEnd

        private final float rotateEnd
        Coarse and fine sampling parameters.
      • coarseRate

        private final float coarseRate
        Coarse and fine sampling parameters.
      • fineRate

        private final float fineRate
        Coarse and fine sampling parameters.
      • simpleInput

        private ModelSimpleImage simpleInput
        Simple version of input image.
      • simpleInputSub2

        private ModelSimpleImage simpleInputSub2
        Simple version of input image, subsampled by 2.
      • simpleInputSub4

        private ModelSimpleImage simpleInputSub4
        Simple version of input image, subsampled by 4.
      • simpleInputSub8

        private ModelSimpleImage simpleInputSub8
        Simple version of input image, subsampled by 8.
      • simpleRef

        private ModelSimpleImage simpleRef
        Simple version of reference image.
      • simpleRefSub2

        private ModelSimpleImage simpleRefSub2
        Simple version of reference image, subsampled by 2.
      • simpleRefSub4

        private ModelSimpleImage simpleRefSub4
        Simple version of reference image, subsampled by 4.
      • simpleRefSub8

        private ModelSimpleImage simpleRefSub8
        Simple version of reference image, subsampled by 8.
      • simpleWeightInput

        private ModelSimpleImage simpleWeightInput
        Simple version of weighted input image.
      • simpleWeightInputSub2

        private ModelSimpleImage simpleWeightInputSub2
        Simple version of weighted input image, subsampled by 2.
      • simpleWeightInputSub4

        private ModelSimpleImage simpleWeightInputSub4
        Simple version of weighted input image, subsampled by 4.
      • simpleWeightInputSub8

        private ModelSimpleImage simpleWeightInputSub8
        Simple version of weighted input image, subsampled by 8.
      • simpleWeightRef

        private ModelSimpleImage simpleWeightRef
        Simple version of weighted reference image.
      • simpleWeightRefSub2

        private ModelSimpleImage simpleWeightRefSub2
        Simple version of weighted reference image, subsampled by 2.
      • simpleWeightRefSub4

        private ModelSimpleImage simpleWeightRefSub4
        Simple version of weighted reference image, subsampled by 4.
      • simpleWeightRefSub8

        private ModelSimpleImage simpleWeightRefSub8
        Simple version of weighted reference image, subsampled by 8.
      • transform

        private AlgorithmTransform transform
        Transformation algorithm for creating an isotropic reference image.
      • transform2

        private AlgorithmTransform transform2
        Transformation algorithm for creating an isotropic input image.
      • weighted

        private boolean weighted
        Flag to determine if there are weighted images or not.
      • weightedInputPixels

        private int weightedInputPixels
        DOCUMENT ME!
      • weightedInputPixelsSub2

        private int weightedInputPixelsSub2
        DOCUMENT ME!
      • weightedInputPixelsSub4

        private int weightedInputPixelsSub4
        DOCUMENT ME!
      • weightedInputPixelsSub8

        private int weightedInputPixelsSub8
        DOCUMENT ME!
      • weightedRefPixels

        private int weightedRefPixels
        DOCUMENT ME!
      • weightedRefPixelsSub2

        private int weightedRefPixelsSub2
        DOCUMENT ME!
      • weightedRefPixelsSub4

        private int weightedRefPixelsSub4
        DOCUMENT ME!
      • weightedRefPixelsSub8

        private int weightedRefPixelsSub8
        DOCUMENT ME!
      • paths

        private final java.util.Vector<java.util.Vector<WildMagic.LibFoundation.Mathematics.Vector3f>>[] paths
        Used to store all paths for levelEigth, levelFour, levelTwo and levelOne.
      • optimalPath

        private java.util.Vector<WildMagic.LibFoundation.Mathematics.Vector3f> optimalPath
        The optimal path.
      • originalPath

        private static final WildMagic.LibFoundation.Mathematics.Vector3f[] originalPath
    • Constructor Detail

      • AlgorithmRegOAR2D

        public AlgorithmRegOAR2D​(ModelImage _imageA,
                                 ModelImage _imageB,
                                 int _costChoice,
                                 int _DOF,
                                 int _interp,
                                 float _rotateBegin,
                                 float _rotateEnd,
                                 float _coarseRate,
                                 float _fineRate,
                                 boolean doSubsample,
                                 boolean doMultiThread)
        Creates new automatic linear registration algorithm and sets necessary variables.
        Parameters:
        _imageA - Reference image (register input image to reference image).
        _imageB - Input image (register input image to reference image).
        _costChoice - Choice of cost functions, like correlation ratio or mutual information.
        _DOF - Degrees of freedom for registration
        _interp - Interpolation method used in transformations.
        _rotateBegin - Beginning of coarse sampling range (i.e., -60 degrees).
        _rotateEnd - End of coarse sampling range (i.e., 60 degrees).
        _coarseRate - Point at which coarse samples should be taken (i.e., every 45 degrees).
        _fineRate - Point at which fine samples should be taken (i.e., every 15 degrees).
        doSubsample - If true subsample
        doMultiThread -

        Constructor without weighting and without advanced settings (num iter).

      • AlgorithmRegOAR2D

        public AlgorithmRegOAR2D​(ModelImage _imageA,
                                 ModelImage _imageB,
                                 int _costChoice,
                                 int _DOF,
                                 int _interp,
                                 float _rotateBegin,
                                 float _rotateEnd,
                                 float _coarseRate,
                                 float _fineRate,
                                 boolean doSubsample)
        Creates new automatic linear registration algorithm and sets necessary variables.
        Parameters:
        _imageA - Reference image (register input image to reference image).
        _imageB - Input image (register input image to reference image).
        _costChoice - Choice of cost functions, like correlation ratio or mutual information.
        _DOF - Degrees of freedom for registration
        _interp - Interpolation method used in transformations.
        _rotateBegin - Beginning of coarse sampling range (i.e., -60 degrees).
        _rotateEnd - End of coarse sampling range (i.e., 60 degrees).
        _coarseRate - Point at which coarse samples should be taken (i.e., every 45 degrees).
        _fineRate - Point at which fine samples should be taken (i.e., every 15 degrees).
        doSubsample - If true subsample

        Constructor without weighting and without advanced settings (num iter).

      • AlgorithmRegOAR2D

        public AlgorithmRegOAR2D​(ModelImage _imageA,
                                 ModelImage _imageB,
                                 ModelImage _refWeight,
                                 ModelImage _inputWeight,
                                 int _costChoice,
                                 int _DOF,
                                 int _interp,
                                 float _rotateBegin,
                                 float _rotateEnd,
                                 float _coarseRate,
                                 float _fineRate,
                                 boolean doSubsample,
                                 boolean doMultiThread)
        Creates new automatic linear registration algorithm and sets necessary variables.
        Parameters:
        _imageA - Reference image (register input image to reference image).
        _imageB - Input image (register input image to reference image).
        _refWeight - Reference weighted image, used to give certain areas of the image greater impact on the registration.
        _inputWeight - Input weighted image, used to give certain areas of the image greater impact on the registration.
        _costChoice - Choice of cost functions, like correlation ratio or mutual information.
        _DOF - Degrees of freedom for registration
        _interp - Interpolation method used in transformations.
        _rotateBegin - Beginning of coarse sampling range (i.e., -60 degrees).
        _rotateEnd - End of coarse sampling range (i.e., 60 degrees).
        _coarseRate - Point at which coarse samples should be taken (i.e., every 45 degrees).
        _fineRate - Point at which fine samples should be taken (i.e., every 15 degrees).
        doSubsample - If true subsample
        doMultiThread -

        Constructor with weighting and without advanced settings (num iter).

      • AlgorithmRegOAR2D

        public AlgorithmRegOAR2D​(ModelImage _imageA,
                                 ModelImage _imageB,
                                 ModelImage _refWeight,
                                 ModelImage _inputWeight,
                                 int _costChoice,
                                 int _DOF,
                                 int _interp,
                                 float _rotateBegin,
                                 float _rotateEnd,
                                 float _coarseRate,
                                 float _fineRate,
                                 boolean doSubsample)
        Creates new automatic linear registration algorithm and sets necessary variables.
        Parameters:
        _imageA - Reference image (register input image to reference image).
        _imageB - Input image (register input image to reference image).
        _refWeight - Reference weighted image, used to give certain areas of the image greater impact on the registration.
        _inputWeight - Input weighted image, used to give certain areas of the image greater impact on the registration.
        _costChoice - Choice of cost functions, like correlation ratio or mutual information.
        _DOF - Degrees of freedom for registration
        _interp - Interpolation method used in transformations.
        _rotateBegin - Beginning of coarse sampling range (i.e., -60 degrees).
        _rotateEnd - End of coarse sampling range (i.e., 60 degrees).
        _coarseRate - Point at which coarse samples should be taken (i.e., every 45 degrees).
        _fineRate - Point at which fine samples should be taken (i.e., every 15 degrees).
        doSubsample - If true subsample

        Constructor with weighting and without advanced settings (num iter).

      • AlgorithmRegOAR2D

        public AlgorithmRegOAR2D​(ModelImage _imageA,
                                 ModelImage _imageB,
                                 int _costChoice,
                                 int _DOF,
                                 int _interp,
                                 float _rotateBegin,
                                 float _rotateEnd,
                                 float _coarseRate,
                                 float _fineRate,
                                 boolean doSubsample,
                                 boolean doMultiThread,
                                 int _baseNumIter,
                                 int _numMinima)
        Creates new automatic linear registration algorithm and sets necessary variables.
        Parameters:
        _imageA - Reference image (register input image to reference image).
        _imageB - Input image (register input image to reference image).
        _costChoice - Choice of cost functions, like correlation ratio or mutual information.
        _DOF - Degrees of freedom for registration
        _interp - Interpolation method used in transformations.
        _rotateBegin - Beginning of coarse sampling range (i.e., -60 degrees).
        _rotateEnd - End of coarse sampling range (i.e., 60 degrees).
        _coarseRate - Point at which coarse samples should be taken (i.e., every 45 degrees).
        _fineRate - Point at which fine samples should be taken (i.e., every 15 degrees).
        doSubsample - If true subsample
        doMultiThread -
        _baseNumIter - Limits the number of iterations of Powell's algorithm. maxIter in the call to Powell's will be an integer multiple of baseNumIter
        _numMinima - Number of minima from level 8 to test at level 4

        Constructor without weighting and with advanced settings (num iter) set.

      • AlgorithmRegOAR2D

        public AlgorithmRegOAR2D​(ModelImage _imageA,
                                 ModelImage _imageB,
                                 int _costChoice,
                                 int _DOF,
                                 int _interp,
                                 float _rotateBegin,
                                 float _rotateEnd,
                                 float _coarseRate,
                                 float _fineRate,
                                 boolean doSubsample,
                                 int _baseNumIter,
                                 int _numMinima)
        Creates new automatic linear registration algorithm and sets necessary variables.
        Parameters:
        _imageA - Reference image (register input image to reference image).
        _imageB - Input image (register input image to reference image).
        _costChoice - Choice of cost functions, like correlation ratio or mutual information.
        _DOF - Degrees of freedom for registration
        _interp - Interpolation method used in transformations.
        _rotateBegin - Beginning of coarse sampling range (i.e., -60 degrees).
        _rotateEnd - End of coarse sampling range (i.e., 60 degrees).
        _coarseRate - Point at which coarse samples should be taken (i.e., every 45 degrees).
        _fineRate - Point at which fine samples should be taken (i.e., every 15 degrees).
        doSubsample - If true subsample
        doMultiThread -
        _baseNumIter - Limits the number of iterations of Powell's algorithm. maxIter in the call to Powell's will be an integer multiple of baseNumIter
        _numMinima - Number of minima from level 8 to test at level 4

        Constructor without weighting and with advanced settings (num iter) set.

      • AlgorithmRegOAR2D

        public AlgorithmRegOAR2D​(ModelImage _imageA,
                                 ModelImage _imageB,
                                 ModelImage _refWeight,
                                 ModelImage _inputWeight,
                                 int _costChoice,
                                 int _DOF,
                                 int _interp,
                                 float _rotateBegin,
                                 float _rotateEnd,
                                 float _coarseRate,
                                 float _fineRate,
                                 boolean doSubsample,
                                 boolean doMultiThread,
                                 int _baseNumIter,
                                 int _numMinima)
        Creates new automatic linear registration algorithm and sets necessary variables.
        Parameters:
        _imageA - Reference image (register input image to reference image).
        _imageB - Input image (register input image to reference image).
        _refWeight - Reference weighted image, used to give certain areas of the image greater impact on the registration.
        _inputWeight - Input weighted image, used to give certain areas of the image greater impact on the registration.
        _costChoice - Choice of cost functions, like correlation ratio or mutual information.
        _DOF - Degrees of freedom for registration
        _interp - Interpolation method used in transformations.
        _rotateBegin - Beginning of coarse sampling range (i.e., -60 degrees).
        _rotateEnd - End of coarse sampling range (i.e., 60 degrees).
        _coarseRate - Point at which coarse samples should be taken (i.e., every 45 degrees).
        _fineRate - Point at which fine samples should be taken (i.e., every 15 degrees).
        doSubsample - If true subsample
        doMultiThread -
        _baseNumIter - Limits the number of iterations of Powell's algorithm. maxIter in the call to Powell's will be an integer multiple of baseNumIter
        _numMinima - Number of minima from level 8 to test at level 4

        Constructor with weighting and with advanced settings (num iter) set.

      • AlgorithmRegOAR2D

        public AlgorithmRegOAR2D​(ModelImage _imageA,
                                 ModelImage _imageB,
                                 ModelImage _refWeight,
                                 ModelImage _inputWeight,
                                 int _costChoice,
                                 int _DOF,
                                 int _interp,
                                 float _rotateBegin,
                                 float _rotateEnd,
                                 float _coarseRate,
                                 float _fineRate,
                                 boolean doSubsample,
                                 int _baseNumIter,
                                 int _numMinima)
        Creates new automatic linear registration algorithm and sets necessary variables.
        Parameters:
        _imageA - Reference image (register input image to reference image).
        _imageB - Input image (register input image to reference image).
        _refWeight - Reference weighted image, used to give certain areas of the image greater impact on the registration.
        _inputWeight - Input weighted image, used to give certain areas of the image greater impact on the registration.
        _costChoice - Choice of cost functions, like correlation ratio or mutual information.
        _DOF - Degrees of freedom for registration
        _interp - Interpolation method used in transformations.
        _rotateBegin - Beginning of coarse sampling range (i.e., -60 degrees).
        _rotateEnd - End of coarse sampling range (i.e., 60 degrees).
        _coarseRate - Point at which coarse samples should be taken (i.e., every 45 degrees).
        _fineRate - Point at which fine samples should be taken (i.e., every 15 degrees).
        doSubsample - If true subsample
        doMultiThread -
        _baseNumIter - Limits the number of iterations of Powell's algorithm. maxIter in the call to Powell's will be an integer multiple of baseNumIter
        _numMinima - Number of minima from level 8 to test at level 4

        Constructor with weighting and with advanced settings (num iter) set.

    • Method Detail

      • calculateCenterOfMass2D

        public WildMagic.LibFoundation.Mathematics.Vector2f calculateCenterOfMass2D​(ModelSimpleImage image,
                                                                                    ModelSimpleImage wgtImage,
                                                                                    boolean isColor)
        Calculates the center of mass (gravity) of a 2D image. In image space where the upper left hand corner of the image is 0,0. The x axis goes left to right, y axis goes top to bottom. (i.e. the right hand rule). One could simply multiply by voxel resolutions.
        Parameters:
        image - DOCUMENT ME!
        wgtImage - DOCUMENT ME!
        isColor - DOCUMENT ME!
        Returns:
        the center of mass as a 2D point
      • disposeLocal

        public void disposeLocal()
        Dispose of local variables that may be taking up lots of room.
      • finalize

        public void finalize()
        Prepares this class for destruction.
        Overrides:
        finalize in class AlgorithmBase
      • getTransform

        public TransMatrix getTransform()
        Accessor that returns the matrix calculated in this algorithm.
        Returns:
        Matrix found at the end of algorithm.
      • drawLine

        public void drawLine​(int xdim,
                             int ydim,
                             int zdim,
                             double[] image,
                             float value,
                             java.util.Vector<Point3D> path)
      • param2Coordinates

        public java.util.Vector<WildMagic.LibFoundation.Mathematics.Vector3f> param2Coordinates​(double startX,
                                                                                                double endX,
                                                                                                double stepX,
                                                                                                double startY,
                                                                                                double endY,
                                                                                                double stepY,
                                                                                                double startZ,
                                                                                                double endZ,
                                                                                                double stepZ,
                                                                                                java.util.Vector<WildMagic.LibFoundation.Mathematics.Vector3f> path)
      • findPointsOfLine

        public java.util.Vector<Point3D> findPointsOfLine​(java.util.Vector<WildMagic.LibFoundation.Mathematics.Vector3f> realPath)
      • midpointLine

        public void midpointLine​(WildMagic.LibFoundation.Mathematics.Vector3f p0,
                                 WildMagic.LibFoundation.Mathematics.Vector3f p1,
                                 java.util.Vector<Point3D> imagePath)
      • line

        public float line​(float a,
                          float b,
                          int x,
                          float y)
      • runAlgorithm

        public void runAlgorithm()
        Runs the image registration. Blurs the images based on what their minimum resolutions are. The reference image is blurred if one of the input image resolutions is 50% or more bigger than the corresponding resolution in the reference image; likewise, the input image is blurred if one of the reference image resolutions is 50% or more bigger than the corresponding resolution in the input image. Thus, it is unlikely, though not impossible, that both images will be blurred. The images are then transformed into isotropic voxels. The resolutions of the two images after the isotropic transformation will be the same in all dimensions. That resolution will equal the minimum of the minimums of each image's resolutions: Min( Min (resolutions of ref image, resolutions of input image) ). If the images are weighted, the weight images are blurred and transformed into isotropic voxels in the same manner as the originals. Then the images are subsampled by 2, 4, and 8. If the images are too small they will not be subsampled down to the smallest level; if they are too big, they will be subsampled to 16. The same is done with the weight images if necessary. The function levelEight is called with the images subsampled by 8; it returns two vectors with minima. Then the function levelFour is called with images subsampled by 4 and the two vectors; it returns one vector of minima. The function levelTwo is called with images subsampled by 2 and the vector; it returns an "answer" in the form of a MatrixListItem, which is a convenient way of storing the point, the matrix, and the cost of the minimum. Then the function levelOne is called with the minimum; it returns a final "answer", or minimum, which will then be accessed by the dialog that called this algorithm.
        Specified by:
        runAlgorithm in class AlgorithmBase
      • getCost

        public double getCost()
      • getRotation

        public double getRotation()
      • createTerrain

        private void createTerrain()
      • searchOptimalPath

        private void searchOptimalPath()
      • indexOf

        private int indexOf​(java.util.Vector<java.util.Vector<WildMagic.LibFoundation.Mathematics.Vector3f>> aPaths,
                            WildMagic.LibFoundation.Mathematics.Vector3f tp3d)
      • print

        public void print​(java.util.Vector data,
                          java.lang.String message)
      • print

        public void print​(MatrixListItem item,
                          java.lang.String message)
      • setBruteForce

        public void setBruteForce​(boolean bOn,
                                  float fRotationRange,
                                  float fXScaleRange,
                                  float fYScaleRange,
                                  int iScaleSteps,
                                  int iTranslationRange)
        setBruteForce. Tells the algorithm to do a brute-force optimization, where it will iterate of the the input rotation, xscale, yscale, and translation ranges calculating the cost function at each point and returing the minimum. No optimization with the brute-force approach.
        Parameters:
        bOn - DOCUMENT ME!
        fRotationRange - DOCUMENT ME!
        fXScaleRange - DOCUMENT ME!
        fYScaleRange - DOCUMENT ME!
        iScaleSteps - DOCUMENT ME!
        iTranslationRange - DOCUMENT ME!
      • setJTEM

        public void setJTEM​(boolean bOn)
      • subsampleBy2

        private static ModelSimpleImage subsampleBy2​(ModelSimpleImage srcImage,
                                                     boolean isColor)
        Takes a simple image and subsamples it by 2, interpolating so that the new values are averages.
        Parameters:
        srcImage - Image to subsample.
        isColor - DOCUMENT ME!
        Returns:
        Subsampled image.
      • algorithmBruteForce

        private void algorithmBruteForce()
        Compute the brute-force solution. Iterates over a range of angles, scales and translations, calculating the cost function for each new position, returning the one with minimum cost:
      • getConstructionInfo

        private java.lang.String getConstructionInfo()
        Creates a string with the parameters that the image was constructed with.
        Returns:
        Construction info.
      • getTolerance

        private double[] getTolerance​(int DOF)
        Gets the tolerance vector based on the degrees of freedom (the length of the tolerance is the degrees of freedom).
        Parameters:
        DOF - Degrees of freedom, will be length of vector.
        Returns:
        New tolerance vector to send to optimization.

        Based on FLIRT paper: let n=pixel dimension (in one dimension) R=brain radius, here assumed to be half of field-of-view Translation tolerance = n/2 Rotation tolerance = (180/PI)*n/(2R) (converted to degrees because AlgorithmPowell works in degrees) Scaling tolerance = n/(2R) Skewing tolerance = n/(2R)

      • interpolate

        private void interpolate​(double x,
                                 double[] initial,
                                 double[][] tranforms,
                                 boolean scale)
        Performs a bilinear interpolation on points. Takes an initial point, a vector of values to set, and an array in which to look at neighbors of that point. Sets the appropriate values in the vector. Does not set scale if the scale parameter is false.
        Parameters:
        x - Initial index into array.
        initial - Vector to set; if scale is true, set two translations and a scale. Otherwise just set translations.
        tranforms - DOCUMENT ME!
        scale - true means set the scale in the vector.
      • levelEight

        public java.util.Vector<MatrixListItem>[] levelEight​(ModelSimpleImage ref,
                                                             ModelSimpleImage input)
        Takes two images that have been subsampled by a factor of eight. Sets up the cost function with the images and the weighted images, if necessary. Uses the coarse sampling rate and optimizes translations and global scale at the given rotation. So for example, if the coarse sampling range were -30 to 30 at every 15 degrees, we would optimize at rotations of -30, -15, 0, 15, 30. Measures the cost at the fine sampling rate. Interpolates the translations and global scale to come up with a good guess as to what the optimized translation would be at that point. Takes the top 20% of the points and optimizes them. Now have a large multi-array of costs. 20% of those have been optimized and placed back into their original position in the multi-array. Looks at the 2 neighbors of a point: + and - one fine sample. If the point has a cost greater than any of these, it is not a minima. Otherwise it is. Saves it in a vector of minima. Optimizes the minima over rotation as well as translations and global scale. (Previously had not optimized over rotation.) Returns two vectors, one containing the minima before optimization, one containing the minima after optimization.
        Parameters:
        ref - Subsampled by 8 reference image.
        input - Subsampled by 8 input image.
        Returns:
        List of preoptimized and optimized points.
      • levelFour

        public java.util.Vector<MatrixListItem> levelFour​(ModelSimpleImage ref,
                                                          ModelSimpleImage input,
                                                          java.util.Vector<MatrixListItem> minima,
                                                          java.util.Vector<MatrixListItem> optMinima)
        Takes two images that have been subsampled by a factor of four, and two vectors of minima. Sets up the cost function with the images and the weighted images, if necessary. Adds the level4Factor determined during subsampling. Measures the costs of the minima on the images and sort them. Takes the top three in each vector (pre-optimization and post-optimization) and optimizes them. Puts them all into one vector. Perturbs the rotation by zero and plus-minus fineDelta. If it's not a rigid transformation, perturbs the global scaling by factors of 0.8, 0.9, 1.0, 1.1, and 1.2. Optimize the perturbations. Returns a vector of the perturbed, optimized minima.
        Parameters:
        ref - Reference image, subsampled by 4.
        input - Input image, subsampled by 4.
        minima - Preoptimized minima.
        optMinima - Optimized minima.
        Returns:
        A vector of perturbed, optimized minima.
      • levelOne

        public MatrixListItem levelOne​(ModelSimpleImage ref,
                                       ModelSimpleImage input,
                                       MatrixListItem item)
        Takes the two images, no subsampling, and the best minimum so far. Sets up the cost function with the images and the weighted images, if necessary. Adds the level1Factor determined during subsampling. Performs one optimization run, with the maximum allowable degrees of freedom as specified by the user (the max is 7). Returns the best minimum.
        Parameters:
        ref - Reference image.
        input - Input image.
        item - Best minimum so far.
        Returns:
        Best minimum after optimization.
      • levelOne2D

        private MatrixListItem levelOne2D​(ModelSimpleImage ref,
                                          ModelSimpleImage input)
        Only used for translations only = 2 degrees of freedom levelEight, levelFour, and levelTwo are skipped Takes the two images, no subsampling. Sets up the cost function with the images and the weighted images, Performs one optimization run, with 2 degrees of freedom Returns the best minimum.
        Parameters:
        ref - Reference image.
        input - Input image.
        Returns:
        Best minimum after optimization.
      • levelOne2DRotation

        private MatrixListItem levelOne2DRotation​(ModelSimpleImage ref,
                                                  ModelSimpleImage input)
        Only used for rotations only = 1 degrees of freedom levelEight, levelFour, and levelTwo are skipped Takes the two images, no subsampling. Sets up the cost function with the images and the weighted images, Performs one optimization run, with 2 degrees of freedom Returns the best minimum.
        Parameters:
        ref - Reference image.
        input - Input image.
        Returns:
        Best minimum after optimization.
      • levelTwo

        public MatrixListItem levelTwo​(ModelSimpleImage ref,
                                       ModelSimpleImage input,
                                       java.util.Vector<MatrixListItem> minima)
        Takes two images that have been subsampled by a factor of 2 and a vector of minima. Sets up the cost function with the images and the weighted images, if necessary. Adds the level2Factor determined during subsampling. Measures the costs of the minima at the images. Optimizes the best minimum with 4 degrees of freedom, then 5, then 7. If the user has limited the degrees of freedom to 3, there will only be one optimization run, with 3 degrees of freedom. Returns the best minimum after optimization.
        Parameters:
        ref - Reference image, subsampled by 2.
        input - Input image, subsampled by 2.
        minima - Minima.
        Returns:
        The optimized minimum.
      • getLevel1Factor

        public float getLevel1Factor()
      • setLevel1Factor

        public void setLevel1Factor​(float level1Factor)
      • getLevel2Factor

        public float getLevel2Factor()
      • setLevel2Factor

        public void setLevel2Factor​(float level2Factor)
      • getLevel4Factor

        public float getLevel4Factor()
      • setLevel4Factor

        public void setLevel4Factor​(float level4Factor)
      • getMaxDim

        public int getMaxDim()
      • setMaxDim

        public void setMaxDim​(int maxDim)