echo-filtering

代码说明：

  系统可以利用声音信号产生带有回声的声音文件，并可以从带有回声的文件中消除回声而得到原声音信号；另外，系统还能从中估计反射物的距离(System can make use of the voice signals of the sound files with echoes and echoes from the document with echo and obtain the elimination of the original voice signal In addition, the system can also have to guess the distance from the reflective material)