This paper proposes a two-stage iterative method for removing random-valued impulse noise. In the first phase, we use the adaptive center-weighted median filter to identify pixels which are likely to be corrupted by noise (noise candidates). In the second phase, these noise candidates are restored using a detail-preserving regularization method which allows edges and noise-free pixels to be preserved. In the this paper these two phases are applied alternatively. Simulation results indicate that the proposed method is significantly better than those using just nonlinear filters or detail preservation method only.

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impulse noise high density noise median filter non linear filter Adaptive centre weighted median