1 主动轮廓模型 - 中国图象图形学报.doc

中图法分类号：TP391 文献标识码：A 文章编号：1006-8961(200 ) - - 论文引用格式： 多相主动轮廓模型的眼底图像杯盘分割 郑姗1，2 ， 范慧杰2 ， 唐延东2，王琰1 1.沈阳理工大学信息科学与工程学院, 沈阳 110159； 2.中国科学院沈阳自动化研究所, 机器人学国家重点实验室沈阳 110016 摘 要：目的：视盘及视杯的检测对于分析眼底图像和视网膜视神经疾病计算机辅助诊断来说十分重要，本文利用医学眼底图像中视盘和视杯呈现椭圆形状这一特征，提出了椭圆约束下的多相主动轮廓模型，实现视盘视杯的同时、精确分割。该方法根据视盘视杯在灰度图像中具有不同的区域亮度，建立多相主动轮廓模型，然后将椭圆形约束内嵌于该模型中。通过对该模型的能量泛函进行求解，得到椭圆参数的演化方程。分割时首先设定两条椭圆形初始曲线，根据演化方程，驱动曲线分别向视盘和视杯方向进行移动，当轮廓线到达视盘、视杯边缘时，曲线停止演化。我们在不同医学眼底图像中对算法进行验证，对算法抗噪性、不同初始曲线选取等进行了实验，并与多种算法进行了对比。实验表明本文模型能够同时分割出视盘及视杯，与其它模型的分割结果相比，本文的分割结果更加准确。结论：我们提出了一种新的眼底图像分割方法，实验结果表明，本文算法可以精确分割医学眼底图像中的视盘和视杯，算法不需要预处理，具有较强的鲁棒性抗噪性。 Automatic segmentation of optic disc and optic cup Using multiphase active contour model in fundus images Zheng Shan1, 2, Fan Huijie2, Tang Yandong2, Wang Yan1 1. College of Information Science and Engineering, Shenyang Ligong University, Shenyang 110159, China; 2. State Key Laboratory of Robotics, Shenyang Institute of Automation, Chinese academy of Sciences, Shenyang 110016, China; Abstract: Objective: Detection of the optic disc and optic cup is very important, which is used to analyze the fundus images and for computer-aided diagnosis of optic nerve disease. In this paper, elliptical multiphase active contour model is proposed by the character of oval shape of optic disc and optic cup. The new algorithm can segment the optic disc and optic cup at the same time and exactly. Method: First, based on the optic disc and optic cup in gray images with different brightness, multiphase active contour model is developed, then, the oval constraints are embedded in the model. By the finding the solution for the energy functional of the model can obtain the parametric equation of ellipse. We first set two oval initial curves, the evolution equation drive curves move towards the direction of the optic disc and optic cup respectively, the curves evolution halt when they reach the object contour border. Result: Through validation of the algorithm to different medical fundus ima