几种典型数字图像中值滤波算法的对比分析

中值滤波方法是图像去除噪声的重要方法之一，广泛应用于数字图像处理中。本文为了更好地检验滤波方法的效果，在图像中添加随机和椒盐两种常见噪声，对多级中值滤波、开关中值滤波和极值中值滤波算法进行仿真，以峰值信噪比和归一化均方差（NMSE）作为客观评价标准，对几种典型中值滤波算法进行了对比分析。结果表明，中值滤波既可以去除图像中的噪声又能保护图像的边缘和轮廓。

Comparative Analysis of Several Typical Digital Image Median Filtering Algorithms

Median filtering method is one of the important digital image de-noising methods, which is widely used in digital image processing. In order to better test the effectiveness of filtering method, the paper adds the ran-dom noise and the Salt and Pepper noise in the image to simulate multi-level median filtering, switching median filtering and extremum median filtering, and compares and analyzes their processing results by using PSNR and NMSE as the evaluation criteria. The test results show that median filtering algorithms can not only remove the im-age noise but also protect its edge and contour.