METHOD FOR REUSING NONACTIVE LABELS IN OBJECT LABELING IN A BLACK/WHITE PEL ARRAY.

A method is reported for reusing nonactive labels in the component labeling of objects in a black/white pel (picture element) array. New labels are assigned to nonconnected pels as a window scans the array in row major order. The method steps include classifying a label as nonactive if it was assigned to some pels in a previous scan line but is not assigned to any pel in a current line. The label will not be assigned if none of the pels having this label can be adjacent to any pel in the next line. The nonlabels are in effect stored and releasable for reuse while the labeling operation continues in one mode.