Impulse noise suppression with an augmentation of ordered difference noise detector and an adaptive variational method

In this letter, we propose an algorithm combining an impulse noise detector with a detail-preserving variational method for removing salt and pepper noise. Firstly, an impulse noise detector is presented, by augmenting the ordered difference of the current pixel value with other pixels’ value in the sliding window to determine whether the current pixel is a noise pixel or not. Then, these noise pixels are restored using the variational method, which can preserve image edges and details. In the variation iteration process, an adaptive scheme of selecting neighbors of a noise candidate is proposed. As a result, noise free pixels remains and image details are preserved after applying our combined algorithm. Experiments for comparison indicate that the proposed algorithm is better than other impulse noise reduction methods in terms of noise removal and edge preservation.