说明：  图像去噪是信号处理的一个经典问题，传统的去噪方法多采用平均或线性方法进行，常用的是维纳滤波，但是去噪效果不太好。随着小波理论的日益完善，其以自身良好的时频特性在图像去噪领域受到越来越多的关注，开辟了用非线性方法去噪的先河。
(Image denoising is a classical problem in signal processing. The traditional denoising methods mostly use average or linear methods. Wiener filtering is commonly used, but the effect of denoising is not good. With the improvement of wavelet theory, it has attracted more and more attention in the field of image denoising with its good time-frequency characteristics, and pioneered the use of non-linear methods to denoise.)