一种不规则虹膜的预处理方法-湖南理工学院.PDFVIP

第 29 卷 第 3 期 湖南理工学院学报( 自然科学版) Vol.29 No.3 2016 年 9 月 Journal of Hunan Institute of Science and Technology (Natural Sciences) Sep. 2016 一种不规则虹膜的预处理方法 彭丽娟, 李建良 (南京理工大学 理学院, 南京 210094) 摘 要: 根据虹膜近似圆形但非圆的特点, 给出了一种虹膜内边界不规则的定位方法, 利用贝塞尔曲线精确定位. 再 根据虹膜内外边界之间的耦合关系提出一种由粗到精的方法来进行外边界快速定位. 最后针对定位出的虹膜常常存在眼脸 的干扰, 提出了一种用改进的 canny 算子结合最小二乘法进行眼脸定位的方法. 最终实验结果表明: 该方法有较高的定位 准确度, 虹膜内边界定位更接近真实边界, 明显改善了定位准确率及效率. 关键词: 虹膜定位; 眼脸定位; 贝塞尔曲线; 改进的canny 算子; 最小二乘法 中图分类号: TP391.41 文献标识码: A 文章编号: 1672-5298(2016)03-0026-05 Preprocessing Method Based on a Kind of Irregular Iris PENG Li-juan , LI Jian-liang (school of science, Nanjing University of Science and Technology, Najing, jiangsu 210094) Abstract: According to the characteristics of the iris which approximate a circle but is not a circle, we present an iris inner boundary irregular positioning method and use Bezier curve to locate precisely. Then based on the coupling relationship of the iris between internal and external boundary, we present a fast positioning method for outer boundary from coarse to fine. Finally, for the located iris is often with eyelid interference, we put forward an improved canny operator and least squares method to detect eyelid edge. The experimental results show that the location accuracy of this method is higher, and the iris inner edge location is much closer to the real boundary. Furthermore, the efficiency and results of the location have been improved obviously． Key words: iris location; eyelid location; bezier curve; improved canny operator; least squares 引言 在生物认证领域中, 以虹膜为特征的身份识别系统扮演了非常重要的角色, 虹膜定位则是虹膜识别 技术中耗时最长且最为关键的环节. 然而虹膜定位的准确率及