Bidirectional Local Distance (BLD)

Function for calculating the Bidirectional Local Distance, BLD, between two point clouds.

Bidirectional-Local-Distance

Matlab function for calculating the Bidirectional Local Distance (BLD) from two sets of points. The BLD is a sort of generalization of the Hausdorff distance. Whereas the Hausdorff distance is a single value which represents the worst-case distance between the two clouds, the BLD gives one distance for each point in the reference cloud. The maximum BLD is the Hausdorff distance.

The BLD was defined by Hak Soo Kim, Samuel B. Park, Simon S. Lo, James I. Monroe, Jason W. Sohn in their paper Bidirectional local distance measure for comparing segmentations, https://doi.org/10.1118/1.4754802, in Medical Physics.

The code works for any dimensionality of the points.

Usage:

d = bld(ref, test)

Here, ref is the reference point cloud, and test is the test point cloud. The output d will contain one value for each point in ref, which is the local distance (BLD) at this point.