最基本的背景差分（background subtract）方法：frame difference。-the basic background subtract method: frame difference.

对复杂背景下的图像进行双边滤波，利用源图像与处理后的图像作差，实现对复杂背景下小目标的检测-First, deal with the image within complex background by bilateral filtering , then original Image subtract the image after bilateral filtering，realize small target detection under complex background