基于双窗口和极值压缩的自适应中值滤波

An Adaptive Median Filter Based on the Double Windows and Extremum-compressing

为了提高中值滤波器的滤波性能和适应不同密度的椒盐脉冲噪声,从噪声检测的准确性、噪声滤除的有效性和滤波速度的实用性等3个方面分别对中值滤波方法加以改进,提出了一种基于双窗口和极值压缩的自适应中值滤波方法(DWECAMF)。该方法采用大窗口检测噪声和小窗口滤除噪声的滤波策略、压缩噪声滤除窗口内极大值和极小值策略以及自适应脉冲噪声滤除策略,以提高图像滤波性能,同时采用了移动滤波策略提高滤波速度以增强其实用性。实验表明,该方法在以上3个方面的性能都有极大提高,并且对不同密度的椒盐噪声都具有很好的滤波性能。

To improve the performances of median filter and enhance the adaptability for the diverse density pepper and salt noises an adaptive median filter, based on the double windows and extremum-compressing filtering （DWECAMF）, is proposed for images corrupted with pepper and salt noises. The filter is improved from the standard median filter on the three standpoints： accurateness of noise detection, validity of noise removal and practicability of filtering speed. The method employs some strategies, such as using the large window for noise detection and the small window for noise removal, compressing the maximum and the minimum within the window for noise removal, and using the adaptive filter for impulsive noise removal-to improve the performances of the filter, and the floating filter strategy to accelerate the filtering speed. The experimental results show that the filters＇ s three performances-mentioned above of the filter are all improved greatly. Meanwhile, the filtering performances of the filter are excellent for different noise densities, ranging from low densities, to high densities.