An Offline Verification Scheme of Skilled Handwritten Forgery Documents using Pressure Characteristics

摘要

We introduce an effective approach for offline verification of signatures where the forgeries are skillfully done, i.e., the true and forgery sample appearances are almost alike. Subtle details of temporal information used in online verification are not available offline and are also hard to recover robustly. Thus we take help of the spatial dynamic information like the pen-tip pressure characteristics and emphasize on the extraction of low pressure points. The points result from the ballistic rhythm of a genuine signature which a forgery, however skillful that may be, always lacks. Ten effective features along with low pressure points and pressure multiplication ratio are proposed to make the distinction between a true and a forgery sample. Three different threshold values are also derived for better verification judgements.