用matlab编程绘制矩形窗函数的幅频特性，窗函数形状的长度为10，20，50，100.-Programming using matlab draw rectangle window function of the amplitude-frequency characteristics, the shape of window function of length of 10,20,50,100.

一种快速的多边形和矩形检测算法，可以广泛的应用于各种目标识别领域-A fast polygon and rectangle detection algorithm can be widely used in various areas of target identification