Removal of salt and pepper noise using selective adaptive median filter

Abstract

A selective adaptive median filter is proposed for the restoration of gray scale images that are highly corrupted by salt and pepper noise. In this filter at first the noisy pixel is identified and then it is replaced by a suitable value. Here the size of the window automatically increases until it gets its suitable median value to replace the noisy pixel. This proposed algorithm shows better results than the standard median filter (MF), weighted median filter (WMF), switching mean median filter (SMMF) and bilateral filter. The proposed algorithm is tested against different gray scale images and it gives better Peak Signal-to-Noise Ratio (PSNR), Mean Square Error (MSE) and Structural Similarity Index (SSIM).