中文说明：图像的各向异性扩散，利用matlab实现Perona_Malik算法，梯度阈值K通过对图像求解2-范数的方法迭代获得
English Description：
The anisotropic diffusion of image is realized by using MATLAB_ In Malik algorithm, the gradient threshold K is obtained iteratively by solving the 2-norm of the image