说明：  对典型图像加入均值为0、方差为0.05的高斯噪声，方差为0.05的斑点噪声，密度为0.05%的椒盐噪声。滤波
(Gaussian noise with a mean of 0, a variance of 0.05, a speckle noise with a variance of 0.05, and a salt and pepper noise with a density of 0.05% were added to a typical image.)