在考察多种二值图像连通区域标记方法的基础上, 提出了一种新的基于图像填充和游程码的二值图像孔洞连通域的标记和表达方法。对二值图像进行一次扫描, 得到所有可能构成孔洞的游程码, 并将游程对应的区域基于特定标记值进行填充。通过判断每个游程与图像上一行像素点标记值的对应关系完成新连通域的建立、游程数据存储和连通区域的合并, 判断每个游程与图像下一行像素点标记值的对应关系完成孔洞的筛选。由于仅需扫描图像一次, 且对每个游程只须进行单独处理, 标记算法的效率较高、复杂度较低。结果表明, 可以快速有效地完成二值图像孔洞连通域的标记。同时, 它还给出孔洞之间的包含关系, 能够有效地实现二值图像的拓扑结构表达。

Investigating various methods for binary image connected area labeling, a new method based on image filling and run-length code for binary image hole connected area labeling is proposed. A thorough scan on binary image to obtain run-length codes which may constitute holes is firstly implemented, and a specific labeling value in the corresponding region is filled. The new connected area establishment, run-length codes storage and connected areas combination are completed by judging the labeling value relationship corresponded with the last row of run-length codes in the image. Selecting of holes is completed by judging the labeling value relationship corresponded with the next row of run-length codes in the image. The method requires only a single pass over the image and treats each run-length code separately, so the labeling algorithm has high efficiency and low complexity. Experimental results show that the method can quickly and effectively complete the hole labeling of binary image. The containment relationship between the holes and the connected areas are got. And the useful topological structure expression of binary image is established.