ADAPTIVE LUM SMOOTHER CONTROLLED BY ADAPTIVE THRESHOLD SYSTEM

Rastislav Lukáč - Stanislav Marchevský

   This paper is focused on a control of an adaptive LUM smoother. A class of rank-order based filters, lower-upper-middle (LUM) filters can be designed for smoothing, sharpening or outlier rejection. When used as smoothers, LUM filters can perform smoothing from no smoothing to that of the median. Thus, the LUM smoother can suppress impulsive noise and preserve signal details, simultaneously. However, the traditional LUM smoother is based on a fixed level of smoothing for the whole image. The methods of adaptive controlled smoothing improve achieved results. In this paper a new design is presented of an adaptive LUM smoother. This approach has full adaptive control and no constraints are imposed. The analysis of the new method is presented. Performance of the proposed methods is evaluated through subjective and objective criteria and compared with the well-known median and LUM smoother.

Keywords: LUM filters, smoother, median, impulsive noise, adaptive threshold

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