Vector median-rational hybrid filters for multichannel image processing

In this paper, a new class of nonlinear filters called Vector Median Rational Hybrid Filters (VMRHF) for multispectral image processing was introduced and applied to color image filtering problem. These filters are based on Rational Functions (RF). The VMRHF is a two-stages filter, which exploits the features of the vector median filter (VM) and those of the vector rational operator (VRF) (The output is the result of vector rational operation taking into account three sub-functions, such as two vector median sub-filters and one center weighted vector median filter (CWVMF)). These filters exhibit desirable properties, such as, edge and details preservation and accurate chromaticity estimation. The performances of the proposed filter are compared with those of the vector median and the directional-distance filters (DDF).