多次迭代滑动平均算法，是选一矩形窗口，在平面上逐点滑动，计算窗口内所有点的平均值及观测值与此平均值之差-Multiple iterative moving average algorithm is to　a rectangular window, sliding on the plane point by point, calculate the average value of all the points in the window and the difference between the observed and the average