说明：   本程序对同一图像增加噪声后，进行均值滤波、高斯平滑滤波和中值滤波三种方法的去噪和结果比较， 并进行了评价指标PSNR和SSIM的计算以及算法耗时的统计。
( The program on the same image after the noise increases, mean filter, de-noising and results of the Gaussian smoothing filter and median filter three methods of comparison, and the index PSNR and SSIM calculation algorithm and time-consuming statistics.)