Adaptive median filtering algorithm based on slope

Abstract

For estimating and removing the salt-and-pepper noise point accurately in image,a new adaptive median filtering algorithm was proposed.Firstly,if the pixel in the center of n×n(n is an odd integer not less than three) template was the extreme value of all the pixels in the window,it was supposed to be probably a noise point.The pixel gray value in the sequence difference between the two scripts and a template sequence of the slope of the pixel gray value within the region were used to determine the mean quasi-adaptive noise point to be the real noise points.Finally,mean filtering was done on the noised pixels.Compared with median filter,the condition of detecting noises with this method has been largely enhanced.And the method can both effectively restrain noises and maintain details.