What is disclosed is a novel system and method for encoding/decoding data in a cover contone image via halftone dot orientation modulation. Arrays of halftone threshold values are used to determine a desired orientation, e.g. 0/90°+/−45° for a given single data value of the original message to be...http://www.google.de/patents/US20100060943?utm_source=gb-gplus-sharePatent US20100060943 - DECODING MESSAGE DATA EMBEDDED IN AN IMAGE PRINT VIA HALFTONE DOT ORIENTATION
