采用平均背景法读取视频每一帧，计算出背景后存为之后差分对，仿真matlab版本2014a其他的没有测试，但是视频读取务必选用黑白视频。(Using the average background method to read video each frame, calculate the background, save as after difference, simulation matlab version of 2014a, the other did not test, but video reading must choose black and white video.)