Online Signature Verification Based On Dynamic Time Warping

With the rapid development of network and communication technologies, there comes an urgent and higher requirement on the verification, which should be more veracious, safe and practicable. For those applications under the network environment, especially in the-commerce related field, it has become a key technique problem to decide a person's identity swiftly, conveniently and accurately.The biometrics has a significant advantage over traditional authentication techniques and is becoming more and more widely used. Handwritten signature verification is one of important research areas of biometrics. Compared with other biometric authentication technologies, it is non-intrusive, convenient and more easily accepted by people. In this thesis, we analyzed Dynamic Time Warping (DTW) method that is the classical arithmetic of online signature verification. And at the same time, we discussed the shortcoming of DTW and the countermeasure we advanced. All of this is discussed based on the handwriting information acquired by F-Tablet, which is a digital tablet and can capture the three dimension writing forces. The main content of the thesis consists of:Firstly, we present the fundamental and flow of DTW arithmetic comprehensively. The limitation of this arithmetic is discussed particularity when applied in signature verification. Then, some scheme are introduced to improve the verification effect..Secondly, a new scheme of DTW using force information based on grapheme matching is proposed. It can resolve matching , future extraction and segmentation. The scheme can strengthen the difference between true and imitative signatures.Then, we proposed an algorithm based on DTW and a fuzzy match method based on envelope curve method. The experimental results showed that the algorithm was valid to overcome the shortcoming of the conventional DTW method and resolve the question logically on the practical application of verification.Paperless office is the most promised application of handwritten signature verification based on credible identity validation. The thesis proposed a systemic scheme aimed at the paperless office of bank. In the end, we designed an online signature verification system.