说明：  数字滤波器 ，用matlab的GUI界面完成，可以对输入的信号进行低通，高通，带通，带阻的选择，同时能设置相应的参数。滤波的类型包括：blackman，boxcar，hanning，hamming
(Digital filter matlab GUI interface, the input signal low pass, high pass, band-pass, band-stop choice, at the same time to set the appropriate parameters. Filter types include: blackman, boxcar, hanning, hamming)