Package gov.nih.mipav.model.algorithms.levelset

Class LseGaussianBlur2

  • public class LseGaussianBlur2
extends LsePdeFilter2

    This class implements the Gaussian blur filter for 2D images using a finite-difference-based solver for the partial differential equation:

        du/dt = Laplacian(u)

    where u(x,y,t) is the evolved image at time t, du/dt is the time derivative of u, and Laplacian(u) = u_xx + u_yy, a sum of second-order derivatives of u.

    Version:
    0.1 November 7, 2006
    Author:
    David Eberly

    • Field Detail

      • m_fMaximumTimeStep

        private float m_fMaximumTimeStep
        The maximum time step allowed for numerical stability of the filter.

    • Constructor Detail

      • LseGaussianBlur2

        public LseGaussianBlur2​(int iXBound,
                        int iYBound,
                        float fXSpacing,
                        float fYSpacing,
                        float[] afData,
                        boolean[] abMask,
                        float fBorderValue,
                        int eScaleType)
        Creates a new LseGaussianBlur2 object.
        Parameters:
        iXBound - The x-bound of the image.
        iYBound - The y-bound of the image.
        fXSpacing - The x-spacing of the image.
        fYSpacing - The y-spacing of the image.
        afData - The image elements, stored in lexicographical order.
        abMask - The image mask, stored in lexicographical order. A pixel value is processed by the PDE solver only when the mask value is false.
        fBorderValue - Specifies how to handle the image value. When set to Float.MAX_VALUE, Neumann conditions are in use, in which case zero-valued derivatives are assumed on the image border. Otherwise, Dirichlet conditions are used, in which case the image is assumed to be constant on the border with value specified by fBorderValue.
        eScaleType - The type of scaling to apply to the input image. The choices are NONE, UNIT, SYMMETRIC, or PRESERVE_ZERO.

    • Method Detail

      • getMaximumTimeStep

        public final float getMaximumTimeStep()
        Get the maximum time step for numerical stabilty of the filter.
        Returns:
        The maximum time step.

      • onUpdate

        protected void onUpdate​(int iX,
                        int iY)
        The per-pixel update function of the PDE solver.
        Specified by:
        onUpdate in class LsePdeFilter2
        Parameters:
        iX - The x-value of the pixel to be updated.
        iY - The y-value of the pixel to be updated.