OBJECT ANALYSIS OF MULTI-VALUED IMAGES

Method and apparatus for analyzing a 2-dimensional sensory-input field containing three or more distinct classes of objects. The field is represented by a 2-dimensional array of elements in which each separate class of objects in the field has a separate classification value. The field is scanned with a 2.times.2 window containing the element being scanned and three adjacent and connected window elements, where each of the adjacent window elements has been previously assigned an object label which identifies one object containing that element. If the element being scanned has the same classification value as any of the adjacent window element, it is assigned the object label of that same-classification window element. Otherwise, the element being scanned is assigned a new label. If the element being scanned has the same classification value as two adjacent and orthogonal elements, and these orthogonal elements have been previously given different object labels, the two different object labels are merged. The result is to identify each separate object in the image. Geometric properties of the objects can be calculated during the scanning procedure.