Shaping classification boundaries in template protection systems

Abstract

The invention relates to a method of authentication of a physical object and an apparatus applying said method. The method uses a helper data (W) and a control value (V) associated with a reference object to generate a first property set (C) using the helper data (W) and a metric (Y) associated with the physical object. It further comprises a step to generate a second property set (S) using a noise compensating mapping (NCM) on the first property set (C), as well as a step to establish a sufficient match between the physical object and the reference object using the second property set (S) and the first control value (V). The method is characterized by a step that generates an error measure (ERR) by quantifying the noise removed by the noise compensating mapping (NCM) using the first property set (C) and information derived from the noise compensating mapping (NCM). Error measure (ERR) is subsequently used for generating an authentication decision (D). Also provided is an apparatus configured to carry out the method.