Multi-stage detection based filtering for removal of impulse noise from images

This paper presents, a new technique for removal of impulse noise from images. By incorporating the rank-conditioned median filtering, a threshold operation on the deviation of the extreme ranks from the healthy pixel-values in the filtering window and the center-weighted median (CWM) based adaptive impulse detection mechanism into the detection framework. An improved impulse detection scheme is developed. The proposed detection scheme followed by rank-ordered mean (ROM) filtering of corrupted pixels effectively reduces impulse noise while preserving the image details. Simulations show-that the proposed scheme works better than the existing schemes in suppressing both fixed-valued and random-valued impulses at different noise ratios.