眼底图像增强及评价  

Enhancement and Assessment of the Fundus Image

作　　者：陈萌梦[1] 熊兴良[1] 李广[1] 张婷婷[1] 

机构地区：[1]重庆医科大学生物医学工程研究室,重庆400016

出　　处：《生物医学工程学杂志》2014年第5期1144-1148,共5页Journal of Biomedical Engineering

基　　金：国家自然科学基金资助项目(60975008)

摘　　要：针对视网膜眼底图像的特点,提出一种新的增强方法。首先进行形态学高帽变换以弱化背景、校正非均匀光照,然后运用有限对比度自适应直方图均衡化(CLAHE)拉伸对比度,增强灰度动态范围,最后使用二维匹配滤波增强图像中有重要临床诊断意义的细节并抑制噪声。在DIARETDB0数据库中进行实验,并利用一种新的无参考图像评价方法对多种增强效果进行客观比较。结果表明,该方法对正常和病变图像都能有效地弱化背景,增强对比度,对视网膜眼底图像的细节增强效果也同样显著,大大提高了图像质量。A new enhancement method is proposed based on the characteristics of fundus images in this paper. Firstly, top-hat transform is utilized to weaken the background. Secondly, contrast limited adaptive histogram equalization （CLAHE） is performed to improve the uneven illumination. Finally, two-dimensional matched filters are designed to further enhance the contrast between blood vessels and background. The algorithm was tested in DIARET- DB0 databases and showed good applicability for both normal and pathological fundus images. A new no-reference image quality assessment method was used to evaluate the enhancement methods objectively. The results demonstra- ted that the proposed method could effectively weaken the background, increase contrast, enhance details in the fun- dus images and improve the image quality greatly.

关 键 词：高帽变换 自适应直方图均衡化 对比度 图像质量评价 

分 类 号：TP391.41[自动化与计算机技术—计算机应用技术]