Signature verification by only single genuine sample in offline and online systems

Abstract

The paper presents innovatory methods and algorithms with experimental results on signature verification. It is mainly focused on applications where there is only one reference signature available for comparison. Such restriction is often present in practice and requires selection of specific methods. In this context, both offline and online approaches are investigated. In offline approach, binary image of the signature is initially thinned to obtain a one pixel-wide line. Then, a sampling technique is applied in order to form the signature feature vector. The identification and verification processes are based on comparing the reference feature vector with the questioned samples using Shape Context algorithm. In the case of online data, the system makes use of dynamic information such as trajectory, pen pressure, pen azimuth and pen altitude collected at the time of signing. After further preprocessing, these functional features are verified by means of Dynamic Time Warping method.