Forget watermarks; new technique "fingerprints" paper
A security research team led by the well-known computer science professor Ed Felten has just finished a study into whether future anticounterfeiting measures might have more luck if they focused on the print medium itself. Is it possible to fingerprint a single sheet of paper?
According to the study's abstract, the answer is yes-and it can be done with commodity hardware. "This paper presents a novel technique for authenticating physical documents based on random, naturally occurring imperfections in paper texture," says the document. "We introduce a new method for measuring the three-dimensional surface of a page using only a commodity scanner and without modifying the document in any way. From this physical feature, we generate a concise fingerprint that uniquely identifies the document.


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