Document validation by signature: a serial multi-expert approach

A three-stage serial multi-expert system for facing the problem of signature verification is proposed. The first two stages, respectively devoted to the recognition of random and simple forgeries and of skilled forgeries, employ suitable criteria for estimating the reliability of the performed classification. In case of uncertainty the signature is forwarded to the successive stage which takes the final decision, taking into account the decisions of the previous stages together with their reliability estimations. Criteria for selecting the features to be used at each stage and for computing classification reliability and reliability thresholds are discussed The obtained results are compared with those achieved, on the same database of 49 writers, by other existing systems