Picture element identification by labelling transformations.

Abstract A labelling scheme that discovers and preserves certain pictorial relationships is described and demonstrated. The defined elemental relationships are detected and the picture elements labelled, by the use of a series of rewrite rules (or transformations) that are applied sequentially to the picture elements during a “once-only” image array scan. An algorithm is described that carries out the labelling transformations and the utility of the procedure is discussed with respect to several nontrivial pattern recognition problems connected with a particular biological image class.