title: Using the fibre structure of paper to determine authenticity of the documents: analysis of transmitted light images of stamps and banknotes.
abstract: A novel method is presented for distinguishing postal stamp forgeries and counterfeit banknotes from genuine samples. The method is based on analyzing differences in paper fibre networks. The main tool is a curvelet-based algorithm for measuring overall fibre orientation distribution and quantifying anisotropy. Using a couple of more appropriate parameters makes it possible to distinguish forgeries from genuine originals as concentrated point clouds in two- or three-dimensional parameter space.
authors.affiliation: Department of Physics, University of Jyväskylä, Finland. Electronic address: jouni.j.takalo@jyu.fi.
authors.forename: Jouni
authors.initials: J
authors.lastname: Takalo
authors.affiliation: Department of Physics, University of Jyväskylä, Finland; Nanoscience Center, University of Jyväskylä, Finland.
authors.forename: Jussi
authors.initials: J
authors.lastname: Timonen
authors.affiliation: Department of Mathematics and Statistics, Technical University of Lappeenranta, Finland; Department of Mathematics and Statistics, University of Helsinki, Finland.
authors.forename: Jouni
authors.initials: J
authors.lastname: Sampo
authors.affiliation: Department of Mathematics and Statistics, University of Helsinki, Finland.
authors.forename: Maaria
authors.initials: M
authors.lastname: Rantala
authors.affiliation: Department of Mathematics and Statistics, University of Helsinki, Finland.
authors.forename: Samuli
authors.initials: S
authors.lastname: Siltanen
authors.affiliation: Department of Mathematics and Statistics, University of Helsinki, Finland.
authors.forename: Matti
authors.initials: M
authors.lastname: Lassas
keywords: Counterfeit banknotes; Curvelet; Fibre network; Fibre orientation; Forensic science; Stamp forgeries