关键词: 行程, 子区域, 特征提取, 连通域分析

Abstract: Based on the idea of sub-region，a fast algorithm for Connected Component Analysis（CCA） is proposed to extract features of video targets.Through scanning an image for only one time，the algorithm can describe the equivalences between sub-regions belonging to the same connected component with a multi-tree.And at the same time，features of a target are extracted from leaf nodes to the root node and stored in the root node.It can be demonstrated that the proposed algorithm shows low space and high efficiency by analysis and experimentation.

Key words: run-length, sub-region, feature extraction, connected component analysis