The Use of Static Biometric Signature Data from Public Service Forms

Automatic signature verification/recognition is a commonly used form of biometric authentication. Signatures are typically provided for legal purposes on public service application forms but not used for subsequent biometric recognition. This paper investigates a number of factors concerning the use of signatures in so-called static form (an image of a completed signature) to enable the sample to be used as stand-alone or supplementary data alongside other biometric modalities. Specifically we investigate common sizes of unconstrained signatures within a population, assess the size of application form signing areas with respect to potential constraints and finally investigate performance issues of how constrained and unconstrained enrolment signature data from forms can be accurately matched against constrained and unconstrained verification data, representing the full range of usage scenarios. The study identifies that accuracy can be maintained when constrained signatures data is verified against other constrained samples while the best performance occurs when unconstrained signatures are used for both enrolment and verification.