Fingerprint Recognition Based On The Similar Principle Of Triangle

For the uniqueness permanence and regularity, the fingerprint recognition has become one of the most common and mature techniques in the biological recognition. With the rapid development of the computer technologies and the embedded technique, the fingerprint recognition is applied into confidential security, civil safe, identity recognition, tracking down crimes and other areas as an important individual recognition method.On the basis of the analysis on traditional recognition methods, a new fingerprint recognition solution based on the similar principle of triangle is expatiated, which is made up of the fingerprint image preprocess and character recognition. There are five processes in the preprocess part, which are image normalizing, image filter, orientation estimation, thinning and gray modification. Among them, the modification process can be divided into five steps, which are image smoothing, filter on the middle value, image equilibrium, automatic thresholding and the second thinning. The fingerprint character recognition includes three processes, which are the character extraction, the character triangle coding and the character triangle matching. Based on the mean value and variance, the image normalizing is to reduce the variations of gray between fingerprint ridges and furrows; then, without loss of useful characters, the image is taken off the noises and redundant characters by the filter; after that, the Gauss-Laplace edge detection technique is applied, by which the direction of fingerprint ridges can be confirmed and then the single- pel width ridge image of fingerprint is gotten by the thinning process; in order to filter the algorithm noises, the gray modification process is executed as the last step of the preprocess, and the clear and accurate ridge image is gained finally. According to the connection principle, the fingerprint ending and bifurcation can be extracted; and then the character triangles are gotten, whose peak points are the same type of character points. In the end of the whole algorithm, the character matching based on the theorem of triangle comparability is executed in encrypted code about those triangle's geometrical characters.Experimental results show that the algorithm is accurate and rapid, for the reason of omitting the complicated fingerprint image rotating and zoom .The efficiency and practicability of recognition are enhanced.