应用中值滤波法消除高密度椒盐噪声算法

中值滤波被广泛应用于消除图像的椒盐噪声，对于图像中的每一个噪声像素，用3×3窗口内非噪声像素平均值代替该噪声像素，然后将其更新为非噪声像素，使它能够立即参与后面相邻噪声像素的均值计算，这样不需要迭代过程和改变窗口尺寸，改进的中值滤波就能滤除高密度椒盐噪声。实验结果表明：本文的算法能有效地消除噪声，较好地保持原始图像的细节；计算时间少，具有较大的实用价值。

An Algorithm for Removal of High Density Salt and Pepper Noise Based on Median Filtering

The process of median filtering which has been widely applied to remove salt and pepper noise is improved in this paper.The mean value of the non noise pixels centered at the current noise pixel in the 3 ×3 window is calculated and the gray of the noise pixel is replaced by the mean value.Then, the noise pixel is changed to non noise pixel.Because the noise pixel can im-mediately join to calculate the mean value of the back adjacent noise pixels , the removal of high density salt and pepper noise doesn’t need to repeat and the size of windows keeps constant.The experimental results show that the proposed method behaves excellently for gray and color images which have different noise ratios .The proposed method can preserve the details of the original image well.Furthermore, the run time for the proposed method is quite short, which makes it possible for the real applications.