  In this paper a novel approach for de noising images corrupted by random
valued impulses has been proposed. Noise suppression is done in two steps. The
detection of noisy pixels is done using all neighbor directional weighted
pixels (ANDWP) in the 5 x 5 window. The filtering scheme is based on minimum
variance of the four directional pixels. In this approach, relatively recent
category of stochastic global optimization technique i.e., particle swarm
optimization (PSO) has also been used for searching the parameters of detection
and filtering operators required for optimal performance. Results obtained
shows better de noising and preservation of fine details for highly corrupted
images.
