求pcm文件的基音周期，用matlab编写，作图说明，用平均幅度差算法修正自相关算法来求基音周期-Find the pitch period pcm files, using matlab, plot descr iption, with the average magnitude difference algorithm for auto-correlation algorithm to find correct pitch

分别取长度N=160和N’=N+K的矩形窗函数作用于语音信号上，首先对其进行中心削 波，比较削波前和削波后语音信号波形，并使得削波后的信号进行乘积并求和，计算延迟为0<K<160时的相关值，并且用得到的相关值来检测语音信号的基音周期，用MATLAB画出图形。 -Length N = 160 were taken and N = N+ K rectangular window function in the role of the speech signal, the f