The Algorithm Research Of Partial Fingerprint Recognition

At present, fingerprint recognition products are always based on minutiae matching algorithm. For some poor quality fingerprint images, such as fingerprint image of the elderly population, crime scene partial fingerprint images, these images have a lot of false minutiae; the traditional recognition algorithm's recognition rate is very low on such images, which restricted fingerprint identification product's promotion and application. Therefore, partial fingerprint recognition has become the bottleneck of fingerprint identification technology's development. How to identify accurately partial fingerprint has become an important issue.This dissertation use fingerprint minutiae features and geometric similarity to identify fingerprint image basing on previous studies, and design fingerprint identification system. Firstly, using image segmentation, equalization, enhancement, binarization, thinning and post-processing algorithm to preprocess the fingerprint image; Secondly, in order to meet the image enlarge without distortion and compression performance requirements for storage space, this dissertation uses improvement algorithm of Douglas-Puck to do vectorization for the fingerprint image after preprocessing, and forms vector graph whose storing content describing the image shape algorithm; Finally, using minutiae characteristics of fingerprint images to carry out the first match, if the image meets the first match, and then using characteristics of fingerprint image geometry similar to carry out the re-matching, if twice matches are satisfied, that is to say, the two fingerprint images come from the same finger.The experimental results show that using preprocessing algorithms can reduce greatly the noise interference and improve the image quality. Image vectorization not only can compress the image storage space, but also can achieve fingerprint image to enlarge without distortion. The final match result shows that the algorithm has good recognition effects for partial fingerprint image, but twice matches will increase the fingerprint recognition complexity, the algorithm needs to be further improved.