Lalonde M, Beaulieu M, Gagnon L
IEEE Trans Med Imaging. 2001 Nov;20(11):1193-200. doi: 10.1109/42.963823.
We report about the design and test of an image processing algorithm for the localization of the optic disk (OD) in low-resolution (about 20 micro/pixel) color fundus images. The design relies on the combination of two procedures: 1) a Hausdorff-based template matching technique on edge map, guided by 2) a pyramidal decomposition for large scale object tracking. The two approaches are tested against a database of 40 images of various visual quality and retinal pigmentation, as well as of normal and small pupils. An average error of 7% on OD center positioning is reached with no false detection. In addition, a confidence level is associated to the final detection that indicates the "level of difficulty" the detector has to identify the OD position and shape.
我们报告了一种用于在低分辨率（约20微米/像素）彩色眼底图像中定位视盘（OD）的图像处理算法的设计与测试。该设计依赖于两个步骤的结合：1）基于豪斯多夫距离的边缘图模板匹配技术，由2）用于大规模目标跟踪的金字塔分解引导。针对包含40张具有不同视觉质量、视网膜色素沉着以及正常和小瞳孔的图像的数据库，对这两种方法进行了测试。在视盘中心定位方面实现了平均7%的误差且无错误检测。此外，最终检测结果还关联有一个置信度，该置信度表明检测器识别视盘位置和形状的“难度级别”。
