net.imglib2.algorithm.morphology.distance

Interface Distance

All Known Implementing Classes:

EuclidianDistanceAnisotropic, EuclidianDistanceIsotropic

public interface Distance

Family of strictly convex, real valued functions that are separable in all dimension. The interface thus specifies just a one-dimensional function that is parameterized by an offset along both the x- and the y-axis. These parameters are passed at evaluation along with the dimension in which the function is to be evaluated.

Two distinct members of the same family, d = f(x) and d' = f(x - x0) + y0, must have exactly one intersection point (for each dimension):

 |{ x : f(x) = f(x -x0) + y0 }| = 1
 

This interface is used in DistanceTransform:

D( p ) = min_q f(q) + d(p,q) where p,q are points on a grid/image.

Author:

Philipp Hanslovsky

Method Summary

Modifier and Type	Method and Description
double	evaluate(double x, double xShift, double yShift, int dim) Evaluate function with family parameters xShift and yShift at position x in dimension dim.
double	intersect(double xShift1, double yShift1, double xShift2, double yShift2, int dim) Determine the intersection point in dimension dim of two members of the function family.

Method Detail

evaluate

double evaluate(double x,
                double xShift,
                double yShift,
                int dim)

Evaluate function with family parameters xShift and yShift at position x in dimension dim.

Parameters:

x - position on x-axis at which function is evaluated

xShift - shift along the x-axis

yShift - shift along y-axis

dim - dimension in which to evaluate

Returns:

Function value at position x

intersect

double intersect(double xShift1,
                 double yShift1,
                 double xShift2,
                 double yShift2,
                 int dim)

Determine the intersection point in dimension dim of two members of the function family. The members are parameterized by xShift1, yShift1, xShift2, yShift2, with xShift1 > xShift2.

Parameters:

xShift1 - shift along the x-axis

yShift1 - shift along the y-axis

xShift2 - shift along the x-axis

yShift2 - shift along the y-axis

dim - dimension in which to evaluate

Returns:

intersection point along axis defined by dim