Package gov.nih.mipav.model.algorithms

Class GenerateDGaussian

java.lang.Object
gov.nih.mipav.model.algorithms.GenerateDGaussian
public class GenerateDGaussian extends Object
Calculates an n-dimensional gaussian volume at a given scale, kernel size, and normalized derivative (through the fourth order) in any of the dimensions. Explanation of normalized derivative: The derivative of n = (1/sqrt(2*PI*sigma*sigma))*exp(-x*x/(2*sigma*sigma)) with respect to x = -(x/(sigma*sigma))*n. 1/2 the integral of the derivative from -infinity to infinity with respect to x or the integral of the derivative from 0 to infinity with respect to x = 1/(sigma * sqrt(2*PI)). Hence, the derivative is normalized by multiplying by the normalizing constant sigma. GenerateGaussian returns the Gaussian, sigma times the first derivative of the Gaussian, sigma squared times the second derivative of the Gaussian, sigma cubed times the third derivative of the Gaussian.
Version:
0.8 Aug 4, 1998
Author:
Matthew J. McAuliffe, Ph.D.

  • Field Summary

    Fields
    Modifier and Type
    Field
    Description
    private double
    denom
    denominator of gaussian coeff.
    private int[]
    derivOrder
    derivative order in each dimension.
    private int[]
    dimLengths
    length of function in pixel in each dim.
    private double[]
    gaussianData
    data storage buffer.
    private boolean
    invert
    DOCUMENT ME!
    private int
    nDims
    number of dimensions.
    private int[]
    pt
    temp point storage.
    private double[]
    sigmas
    standard dev. in each direction

  • Constructor Summary

    Constructors
    Constructor
    Description
    GenerateDGaussian(double[] data, int[] dimLengths, double[] sigmas, int[] derivOrder)
    Initializes class that calculates an n-dim Gaussian.
    GenerateDGaussian(double[] data, int[] dimLengths, double[] sigmas, int[] derivOrder, double denom)
    Initializes class that calculates an n-dim Gaussian.

  • Method Summary

    Modifier and Type
    Method
    Description
    void
    calc(boolean invert)
    Starts the Gaussian calculation.
    void
    finalize()
    Prepares this class for destruction.
    private double
    gaussPt(int[] pt)
    Calculates the Gaussian function at a point.
    private double
    hermite(int order, double num)
    Factor to include when calculating derivatives.
    ModelImage
    makeImage()
    Converts gaussian double buffer to image model object.
    private void
    recursiveCalc(int offset, int dim)
    Starts the Gaussian calculation.

    Methods inherited from class java.lang.Object

    clone, equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

  • Field Details

    • denom

      private double denom
      denominator of gaussian coeff.

    • derivOrder

      private int[] derivOrder
      derivative order in each dimension.

    • dimLengths

      private int[] dimLengths
      length of function in pixel in each dim.

    • gaussianData

      private double[] gaussianData
      data storage buffer.

    • invert

      private boolean invert
      DOCUMENT ME!

    • nDims

      private int nDims
      number of dimensions.

    • pt

      private int[] pt
      temp point storage.

    • sigmas

      private double[] sigmas
      standard dev. in each direction

  • Constructor Details

    • GenerateDGaussian

      public GenerateDGaussian(double[] data, int[] dimLengths, double[] sigmas, int[] derivOrder)
      Initializes class that calculates an n-dim Gaussian.
      Parameters:
      data - storage area of Gaussian function
      dimLengths - length of function in pixels in each dimension
      sigmas - standard dev. in each direction
      derivOrder - derivative order in each dimension

    • GenerateDGaussian

      public GenerateDGaussian(double[] data, int[] dimLengths, double[] sigmas, int[] derivOrder, double denom)
      Initializes class that calculates an n-dim Gaussian.
      Parameters:
      data - storage area of Gaussian function
      dimLengths - length of function in pixels in each dimension
      sigmas - standard dev. in each direction
      derivOrder - derivative order in each dimension
      denom - denominator of the gaussian scale coeffient

  • Method Details

    • calc

      public void calc(boolean invert)
      Starts the Gaussian calculation.
      Parameters:
      invert - Flag indicating inversion

    • finalize

      public void finalize()
      Prepares this class for destruction.
      Overrides:
      finalize in class Object

    • makeImage

      public ModelImage makeImage()
      Converts gaussian double buffer to image model object.
      Parameters:
      UI - pointer to user interface
      Returns:
      image model object containing the gaussian data

    • gaussPt

      private double gaussPt(int[] pt)
      Calculates the Gaussian function at a point.
      Parameters:
      pt - array of ints representing a point where the Gaussian should be calculated.
      Returns:
      DOCUMENT ME!

    • hermite

      private double hermite(int order, double num)
      Factor to include when calculating derivatives.
      Parameters:
      order - derivative order
      num - input factor to correct
      Returns:
      hermite factor

    • recursiveCalc

      private void recursiveCalc(int offset, int dim)
      Starts the Gaussian calculation.
      Parameters:
      offset - offset in data
      dim - present dimension