An enhanced decision based adaptive median filtering technique to remove Salt and Pepper noise in digital images

In this paper, we present an algorithm to remove Salt and Pepper noise from grayscale images. It is an enhanced adaptive median filtering algorithm which initially calculates median without considering noisy pixels in the processing window. If the noise-free median value is not available in the maximum processing window, the last processed pixel value is used as the replacement. Moreover, in extreme situations such as noise corrupted pure black and white images, a threshold value is used to determine the pixel value. Experimental results show that our algorithm can perform better than the other non-linear filters, suppressing noise level more than 90% while preserving visual quality and necessary details of the image.