对任意输入信号进行FFT变换，并显示信号的频谱图-FFT transform

该程序主要是对语音信号进行分析，采用FFT变换求取信号的幅值与频率，然后与以存储模版进行比较，判断信号是否正常。-The process is essentially the voice signal using the FFT algorithm to strike a signal amplitude and frequency, and then to store the template to determine whether the signal is normal.