由于光线的影响,两帧图象中的物体无运动,但灰度稍微有变化,这种情况也会影响检测的准确度,所以对两帧图象的象素点进行比较时,可以让它们相减的差值和某个小的数值比较,而不一定就是和0值比较-As the effect of light, two images of an object without moving, but the gray has changed slightly, this will also affect the accuracy of detection, so the tw