To facilitate the recovery data from an embedded data pattern through the use of a appropriately sized capture window that is randomly positioned within the data pattern, the embedded data pattern is composed of a plurality of identical, one dimensionally or two dimensionally regularly tiled embedded...http://www.google.de/patents/US6000621?utm_source=gb-gplus-sharePatent US6000621 - Tilings of mono-code and dual-code embedded data pattern strips for robust asynchronous capture
