Impulse noise removal utilizing second-order difference analysis

The pending problem that research in random-valued impulse noise filtering has been facing is the inability to distinguish noisy values that do not occur as extreme outliers in comparison with other surrounding pixels. In this paper, we propose a new detection and filtering algorithm that consists of (1) a two-stage detection scheme that employs second-order difference between pixels to determine the integrity of the image pixels and (2) a noise filtering process that estimates the original value of each noisy pixel utilizing the information gathered from (1). Due to its unbiased detection criteria, this method treats both fixed-valued and random-valued noise with extremely high detection rate.