Patent ID: 8122260

Claim:
An authentication apparatus for authentication of a physical object comprising an enrollment means (ENRL), and an authentication means (AUTH), wherein said enrollment means are arranged in measuring reference characteristics of said physical object; generating and storing template data based on said measured reference characteristics; generating and storing a helper data (W 1 ) based on said template data generating and storing a control value (V 1 ); the authentication means being arranged in: obtaining a metric (Y) from the physical object to be authenticated; and further comprising: a first generation means (GM 1 ) arranged to generate a first property set (C 1 ) using the helper data (W 1 ) and the metric (Y) obtained from the physical object, a second generation means (GM 2 ) arranged to subject said first property data set (C 1 ) to a noise compensating mapping (NCM) to compensate for measured noise in said metric (Y) thereby generating a second property set (S 1 ), a comparing means (CMP) arranged to establish a sufficient match between the physical object and the reference object, by verifying whether the second property set (S 1 ) is within a classification boundary (REG 1 ) of the reference object using the first control value (V 1 ) and wherein a noise robust mapping (NRM) determines the classification boundary, the authentication apparatus characterized in that it further comprises: a third generation means (GM 3 ) arranged to generate an error measure (ERR) by quantifying the noise removed by the noise compensating mapping (NCM) using the first property set (C 1 ) and the second property set (S 2 ), and an authentication decision means (ADM) arranged to use said error measure (ERR) to generate an authentication decision (D).