ROOT ANALYSIS OF LUM SMOOTHING TECHNIQUES

Rastislav Lukáč - Stanislav Marchevský

   The nonlinear merit of rank-order based filters precludes the use of frequency analysis and impulse response to characterise the filter properties. Therefore, in nonlinear filtering domain the filter analysis is performed through deterministic properties such as analysis of root signals, ie signals invariant to the additional filtering passes. The statistical properties are derived in the form of output distributions, which are used to study the noise attenuation. This paper focuses on the root signals of LUM (lower-upper-middle) smoothers, where the traditional forms and the adaptive threshold forms are considered.

Keywords: LUM smoother, weighted median, convergence property, root signal

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