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AssigneeHewlett-Packard Development Company, L.P.
InventorsRobert Francis Squibbs, James Thomas Edward McDonnell
Estimating the term…
A physical object includes a base medium, such as a paper sheet, and a memory tag embedded in it or attached to it. The memory tag stores at least one measure/location data pair including a measurement of a location-dependent characteristic of the base medium originally associated with the tag, and a location in or on the object where the measurement was made. Preferably the measure/location data pair is digitally signed and stored in encrypted form. By checking whether the measure included in the stored data pair matches a current measure of the base medium at the indicated location, it is possible to check whether the base medium is the original medium. Apparatus is provided for originally writing the data pair to the memory tag; apparatus is also provided for subsequendy using the data pair for carrying out the checking operation.
A physical object comprising a base medium for receiving an image, said base medium having a memory tag one of embedded in and attached to the base medium, the memory tag storing at least one measure/location data pair comprising a measurement of a location-dependent characteristic of the base medium, and a location in or on the object where the measurement was made, wherein said characteristic varies with said location in a random manner and said at least one data pair is stored in encrypted form and covered by a digital signature that is also stored in the tag.
Dependencies are inferred from the claim text.