Switching-based filter based on Dempster's combination rule for image processing
In this work, a two-pass switching rank-ordered arithmetic mean (TSRAM) filter that preserves image details while effectively suppressing impulse noise is proposed to improve the performance of switching-based median filters. The proposed filter mechanism includes an efficient impulse detector based on the Dempster-Shafer (D-S) evidence theory and a rank-ordered arithmetic mean filter that works by estimating the noise-free ordered mean values excluding the current pixel. A modified Dempster's combination rule is applied to the impulse detector. To improve filtering performance, a simple switching median filter is included to perform second-pass filtering. Experimental results show that the proposed filter outperforms many well-accepted switching-based median filters in terms of both noise suppression and detail preservation, providing excellent robustness at various percentages of impulse noise. (C) 2010 Elsevier Inc. All rights reserved.
impulse noise median filter evidence theory mass function