Pseudo-Euclidean morphological skeleton transform for machine vision

The authors present a generalized morphological skeleton transform (MST) algorithm for rotation-invariant vision applications. Several subclasses of MST are derived from the algorithm by using appropriate sets of structuring elements (SE). The rotational property of an MST is determined by the circularity of its SEs. A pseudo-Euclidean morphological skeleton transform, which uses quasi-circular SEs composed through a dilation interpolation procedure, is proposed. Experimental results show that the pseudo-Euclidean MST gives the best rotation-invariant performance among existing MST subclasses. These quasi-circular SEs can also be used in other morphological transformations requiring rotation-invariant performances