A scanner, which reads machine readable information on an item and
determines its location on the item, also includes one or more video
cameras for determining dimensions of features on the item. A computer
uses the machine readable information to find a record within a data
structure. The record includes dimensions of one or more visible features
of an item corresponding to the machine readable information and
identified according to their location relative to the machine readable
information. These dimensions of features are then compared to the
dimensions of features of the item being scanned to determine whether the
machine readable information read by the scanner matches the item being
scanned.