Svm-DSmT Combination for the Simultaneous Verification of Off-Line and on-Line Handwritten Signatures

A combination handwritten signature veri ̄cation system is proposed for managing con°icts provided from each individual o®-line and on-line support vector machine (SVM), respectively. Basically, the system is divided into three parts: (i) O®-line veri ̄cation system, (ii) on-line veri ̄cation system and (iii) combination module using belief function theory. The proposed framework allows combining the normalized SVM outputs and uses an estimation technique based on the dissonant model of Appriou to compute the belief assignments. Combination is performed using belief models such as Dempster-Shafer (DS) rule and proportional con°ict redistribution (PCR) rule followed by the likelihood ratio-based decision making. Experiments are conducted on the well-known NISDCC signature collection using false rejection and false acceptance criteria. The obtained results show that the proposed combination framework using Dezert-Smarandache (DSm) theory yields the best veri ̄cation accuracy even when individual o®-line and on-line classi ̄cations provide con°icting results.