Minimum Spanning Tree

This method attempts to digitise an entire network of features at once by generating a minimum spanning tree structure that connects a set of points that are likely to be on the features. These points are selected by the user specifying a criterion based on the appearance of the feature in the image.

In the simplest case these points are connected by straight lines, but D'esopo's algorithm can be automatically applied to find the best path between each pair of connected points. To reduce the number of spurious points in the initial set, isolated points can be removed and the set can be thinned before the spanning tree is calculated. The resulting network can be edited to remove any surplus arcs.

Text and images by Mark Dobie, back to Mark's home page