中文说明：小波的应用很广泛，可以用在文件的压缩、去噪等。本代码主要是针对小波在去噪方面的应用。通过先添加噪声，然后用小波去噪的效果。
English Description：
Wavelet is widely used in file compression and denoising. This code is mainly for the application of wavelet in denoising. By adding noise first, and then using wavelet denoising effect.