Study On The On-Line Handwriting Signature Verification Algorithm Based On Discrete Fréchet Distance

In modern society, as a way of protecting information security, identity verification is gradually becoming very important in the field of national security, finance, justice and E-commerce. Traditional methods for verification and recognition can not satisfy the society demands. Fortunately, development of the techniques for recognition and verification of identification based on biometric features provides a more convenient and more reliable solution. As a kind of behavioral feature, signature has advantages of easy acquirement and sharing. It turns out one of the most popular features in identity recognition and verification.A new algorithm for on-line handwriting signature verification is proposed. The algorithm extracts the position coordinates of extreme points of reference signature and test signature in the signature curves, and then uses discrete Fréchet distance as the measure of the curve distance, respectively matching peak points and peak points, and valley points and valley points. Finally, a decision is made to see if the test signature is genuine. A new definition of curve similarity is introduced in the algorithm and a new mathematical model of judging signature curve similarity has been built up on this definition. The algorithm implies shifting and stretching transformation of the signature curves. Methods of pre-processing of signature data and are introduced, and the algorithm of On-Line signature verification based on Discrete Fréchet distance is expounded in this paper. We discuss the solution of the self-adaptive of abnormal curve, and then analyze time complexity of this algorithm. Finally, we particular discuss the extraction, processing and matching of speed curves. In the whole signature verification system, coordinate is defined as a parameter of first step in signature verification system, and speed is defined as a parameter of second step in signature verification system.Finally, this paper presents the experimental results of signature verifieation based on Discrete Fréchet distance, an d analyzes these results of coordinate curves and speed curves, points out the proper value of various parameters in program. By analysis of genuine and forged signature, we get the FAR and FRR of this scheme.The experimental results show that this way of signature verification achieves a higher performance of verification, and has good pratical application and prospect.