Realization Of The Fingerprint Matching And Automatic Fingerprint Verification

Due to their uniqueness and persistence, fingerprints are used as basis of personal identity. Automated fingerprint identification system, a technology of fingerprint identification using computer, is of convenience, high efficiency, security and reliability. It has been applied in many fields such as financial security, data encryption, electronical business and will play a more and more important role in our life.Nowadays, many products of fingerprint have been offered, however, because of the disturbance of image noise and non-linear of the skin elasticity, to achieve an ideal AFIS (Automatic Fingerprint Identification System) is still a difficult research problem. So it is an efficient solution to the problem that to find an efficient and fast algorithm processing fingerprints images, and to study the technology of fingerprint characteristic on computer and network.Based on latest extensive discourses and technology journals in this field, the dissertation is trying to make studies on algorithms of AFIS. Main works are as follow:Fingerprint pre-process. Its purpose is removing noise of fingerprint image and improving definition of fingerprint image and getting the structure of fingerprint ridge, changing fingerprint image to a one gels width image .Which will be beneficial to the follow minutia extraction. Preprocess includes image segmentation, image enhancement, image binarization and thinning. In image segmentation, according to the information of fingerprint apply a simple segmenting algorithm.Fingerprint minutia extraction. Its purpose is getting all true ending and bifurcation .The two kind of minutia can be extracted by using 8-neighborhood cross-calculation algorithm. A minutia extraction post-processing algorithm would delete all false minutia.Fingerprint image matching. Fingerprint image matching is judging whether these two fingerprint images are captured from the same finger. A fingerprint matching algorithm based on the structural information is presented in this paper. Determine in the input fingerprint and the template fingerprint reference point through comparison ridge similar to the selection. Then all details characteristic point acts according to the fingerprint reference point to transform as the polar coordinate. Finally carries on the detail characteristic point matching, determined whether the two fingerprints come from identical finger.This dissertation researched the algorithms of preprocessing,extraction and matching using VC++ on PC. The experiments showed that the algorithms can enhance fingerprint images and can accurately extract image's minutia. The result of matching is approving.