中文说明：我被要求写一个代码，可以检测任何移动物体使用OpenCV。它将用于门系统。而且它是实时的，从摄像机上获取输入，系统需要实时检测运动物体。据我所知，这是运动检测；
English Description：
I am asked to write a code which can detect ANY moving object using OpenCV. It will be used in in-door system. And it is real time, input will be taken from a camera, and system need to detect the moving stuff real time. According to my knowledge this is motion detection.