眼底视网膜血管的分割在眼底视网膜血管病变分析和心脑血管疾病诊断中具有重要的临床应用价值。针对现有视网膜血管割算法分割出的血管边界不够精确光滑以及对低对比度血管分割效果不理想等问题,本文提出一种改进的B样条Ribbon Snake模型,对视网膜图像中的血管进行分割。该方法首先对眼底视网膜图像进行亮度均衡化、去噪等预处理操作,再利用方向线检测算子对血管中心线进行提取,最终在传统B样条Ribbon Snake模型的基础上设计新的宽度能量、区域能量,并利用该模型完成对视网膜血管进行分割。实验结果表明,该方法分割出的血管边界具有精确与光滑的特性,且能对低对比度血管进行有效分割。
The segmentation of retinal blood vessels has an important application value on analysis of retinal vascular lesions and diagnosing cardiovascular diseases. To solve the problem of the poor results of the low - contrast vessels segmentation and rough boundaries for existing retinal blood vessels segmentation algorithms, this paper proposes an improved B - spline Ribbon Snake to segment the retinal vessels. Firstly the paper preprocesses the retinal images through illumination equalization and denoising, and then extracts the vessel centerlines at different directions. Finally, the paper segments retinal blood vessels by designing the width energy and region energy in the B - spline Ribbon Snake model. The results of the experiment shows that the proposed method segmented retinal vessel more accurately and smoothly, and also segments low contrast vessels effectively.