Research Of Automatic Fingerprint Identification System Based On ARM S3C44B0

Fingerprint identification is the process that find the features of fingerprint,compare the feature templates of two fingerprints by fuzzy comparison,calculate their degree of similarity,and finally get the result whether they are the same fingerprint or not.In this paper,a variety of fingerprint identification algorithms are studied and programmed to compare, and an improved thining algorithm is put forward.Besides,an Automatic Fingerprint Identification System is constructed based on S3C44B0 that is a 32-bit processor with ARM7TDMI core as the main controller,and semiconductor capacitance sensor FPS200 as the fingerprint data acquisition equipment.The thesis consists of:(1)Design of fingerprint acquisition module.First the design of FPS200 circuit is completed based on the relevant registers and pin's characteristic. Then the functions of main registers and modes of image acquisition are studied,and flow charts of row image acquisition,sub-image acquisition and whole image acquisition are given respectively.Besides,three working modes are analysed.(2)Research of fingerprint identification algorithm.A variety of preprocessing algorithms are tested,and some problems are found by constrasting their effects.There are much false features such as short ridge, broken ridge,burrs and so on in thinned image,and it is also halfway thinning. So a new restoring algorithm is put forward.By analysising the line's trend around the target point,choose to remove or retain the joined points and this can solve the issue of halfway thinning.Using a square template to track ridge, false features can be removed and this method overcomes the issue that gradually progressive ridge-tracking algorithm is too complex and difficult to achieve.(3)An Automatic Fingerprint Identification System is constructed based on 32-bit RISC processor $3C44B0 of ARM7TDMI core.This system includes power management,fingerprint image acquisition module,memory module,JTAG debug interface and serial interface.Fingerprint acquisition module interface is designed mainly about the hardware part,and the software part includes program of fingerprint image acquisition,fingerprint identification algorithm and serial communication design.Also the fingerprint data is transmitted to PC through the serial port,and an simple identification software is made in VB environment to show the fingerprint image and test fingerprint identification algorithm.