Table I denotes the evaluation made on three kinds of surveillance videos on real situations (voted by volunteers): (1) only one stable camera [3], (2) multi cameras [14], and (3) mobile camera [12]. The first system has problem of occlusion, and small object images due to stable cameras. The second one solves these problems, but small sizes of objects impact significantly to video processing stage. This leads to the low accuracy of the system. The last one is robust to occlusion due to not depending on a fixed camera position, but the view area is too narrow. Besides, it could harass people due to unnaturally installed mobile equipment. In contrast, the proposed system can discover blind corner, compensate occlusion by both fixed and mobile cameras, and avoid moral harassment.