Authentication of security documents, in particular banknotes

US8781205B2 · kind B2 · utility

Assignee

• KBA-NOTASYS SA · CH

Inventors

• Stefan Glock · Lemgo, DE
• Eugen Gillich · Bielefeld, DE
• Johannes Georg Scheade · Würzburg, DE
• Volker Lohweg · Bielefeld, DE

Key dates

• Filing date: Aug 11, 2010
• Grant date: Jul 15, 2014
• Expiry date: Mar 9, 2031

Classification

• Technology area (CPC G): Physics
• CPC primary: G07D7/2016
• WIPO field: Control
• WIPO sector: Instruments

Abstract

There is described a method for checking the authenticity of security documents, in particular banknotes, wherein authentic security documents comprise security features (41-49; 30; 10; 51, 52) printed, applied or otherwise provided on the security documents, which security features comprise characteristic visual features intrinsic to the processes used for producing the security documents. The method comprises the step of digitally processing a sample image of at least one region of interest (R.o.I.) of the surface of a candidate document to be authenticated, which region of interest encompasses at least part of the security features, the digital processing including performing a decomposition of the sample image by means of wavelet transform (WT) of the sample image. Such decomposition of the sample image is based on a wavelet packet transform (WPT) of the sample image, preferably a so-called two-dimensional shift invariant WPT (2D-SIWPT).