Method for the dynamic verification of an autograph character string on the basis of a reference autograph character string

摘要

In a method for dynamic verification of an autograph character string on the basis of a reference autograph character string, the principle of dynamic programming is used for signature verification. Digitized handwriting data as functions of time are first normalized by a standard method. The verification works according to the invention with structural units of the signature, so-called strokes, which result from the writing motions with a raised or, respectively, lowered stylus. The particular concept is to base the dynamic programming on a cost function that combines several handwriting data. The stable structural portions of the signature are more strongly weighted in the method than unstable ones. This leads to a higher verification performance than in standard methods. The method also enables the comparison of signals having different numbers of strokes, so that omissions or additional strokes can be correctly evaluated, by predetermining syntactic rules for their treatment.