此方法是平均背景减除法。主要用于运动目标检测，当然此方法在静止的背景下检测运动目标比较好-Averaging Background Method　　We’ve just seen a simple method of learning background scenes and segmenting fore-　　ground objects. It will work well only with scenes that do not contain moving background components (like a waving curtain or waving trees). It also assumes that the lighting remains fairly constant (as in indoor static scenes).