An efficient data compaction algorithm which reduces the total number of vertices in the polygonal representation of images is presented. The data compaction procedure takes a segmented and polygonally approximated image and transforms it into an ordered list of attribute-minimum cover. The new algorithm incorporates the precedence relation among fields associated with each node of Enclosure Tree as well as enclosure relation among constituent polygons. It is an extension of our previous work which uses only enclosure relation. The algorithm is useful for automated frame creation for pictorial information systems and graphics data compression.