Segmentation and smooth thinning of dorsal hand vein pattern
Xiangbin Liu · Computer Engineering and Applications Journal · 2008
Vein Pattern Recognition is a new contactless biometric technology using IR.Extract vein skeleton with little distortion by thinning the vein pattern separated from the original image is very important to the improvement of successful identification rate.This paper proposes a algorithm to segment,smoothly thin and clip vein pattern based on existing algorithms and analyses of experimentation.Firstly,Gaussian lowpass filter and median filter are used to reduce speck noise and horizontal streak scanning noise in the normalized image respectively,and then the improved NiBlack method and thresholding method based on area are adopted to extract the vein pattern.Subsequently,opening,closing and median filter are applied to smooth the vein edges.Opening and closing are two kinds of morphological operation.Lastly,the improved conditional thinning algorithm and clipping algorithm are employed,and ultimately vein skeletons with little distortion is obtained.The effect of segmentation and thinning is actually improved by the proposed algorithm.