中文摘要：

角膜老年环是一种在角膜边缘形成的白色环状改变,主要由于人体脂类代谢异常而产生。通过图像分析的方法对角膜老年环进行检测可以方便、及时帮助人们发现身体脂类代谢异常状况。自然睁开状态下获取的彩色图像,角膜老年环经常被眼睑随机遮挡,而且被光斑、血管等因素的干扰。为了提高算法鲁棒性,减少由于眼睑的随机遮挡造成的定位失误,提出了一种基于多尺度颜色替换的角膜老年环分割方法。首先对图像进行量化;其次,在不同尺度模板下对图像按照本文定义的颜色替换策略进行处理,并最终实现目标分割。实验结果表明,在采集的1 968幅图像中该方法能够达到97.0%的分割正确率,所用算法具有较高的鲁棒性。

英文摘要：

Corneal arcus is a white ring shape variation formed on the edge of the cornea,which is mainly caused by the abnormal lipid metabolism in human body. This corneal abnormality is significantly associated with the lipid disorder and atherosclerosis. Using image analysis method to detect corneal arcus can help people find the abnormal lipid metabolism in human body conveniently and in time. In the image acquired in natural eye open state,the corneal arcus is often occluded by the eyelid randomly,and disturbed by light spot and blood vessel. In order to improve the robustness of the algorithm and reduce the locating error caused by the random occlusion of the eyelid a corneal arcus segmentation method based on multi-scale color replacement is proposed. Firstly,the image is quantized.Secondly,the image is processed with the defined color replacement strategy under different scale templates. Finally,the object segmentation is achieved. 1 968 images in our database were used to conduct experiment. Experiment results indicate that with the proposed method the segmentation accuracy for the 1 968 images reaches to 97. 0%. The proposed method has high robustness and is not sensitive to noise.