实验前自己用Cool Edit音频编辑软件录制声音“我到北京去”，并把它保存为.txt文件。

编程实现不同矩形窗长N=50、100、200、800的短时平均能量。

用Matlab画出不同窗长的短时平均能量的图形。



-Before the experiment they used Cool Edit audio editing software, record sound, "I go to Beijing," and save it as a. Txt file.

Rectangular windows programming different short average length N = 50,100,200,800 of energy.

Matlab draw a different window with a long term average energy graphics.