Patent ID: 8057032

Claim:
A mobile printing system comprising: (A) a print medium configured to be printed on by a mobile device in a print direction, the print medium comprising a substrate defining first and second opposite faces, the first face having coded tags printed over the first face, each coded tag encoding data indicative of a location of that coded tag on the first face, an identifier of the print medium and a unique digital signature associated with the identifier; and (B) a mobile device comprising: (i) a first sensor for capturing a first image of at least one of the coded tags when the print medium is positioned within a media feed path of the mobile device; (ii) a processor configured for: decoding the data encoded by said coded tag contained in said first image, thereby to determine the location of the sensed coded tag, the identifier and the digital signature; verifying the digital signature; authorizing use of the print medium if the digital signature is verified; and determining the position of the print medium in the media feed path using the determined location of the coded tag contained in the first image; and (iii) a printer for printing information in registration with the coded tag contained in the first image.