L2 Vector Median Filters on Arrays with Reconfigurable Optical Buses

ÐIn spite of their good filtering characteristics for vector-valued image processing, the usability of vector median filters is limited by their high computational complexity. Given an N N image and a W W window, the computational complexity of vector median filter is O…W 4N2†. In this paper, we design three fast and efficient parallel algorithms for vector median filtering based on the 2-norm (L2) on the arrays with reconfigurable optical buses (AROB). For 1 p W q N, our algorithms run in O…W 4 logW=p4†, O…W 4N2 p4q2 logW † and O…1† times using pN= logW , pq= logW , and W N logN processors, respectively. In the sense of the product of time and the number of processors used, the first two results are cost optimal and the last one is time optimal. Index TermsÐParallel algorithm, scalable algorithm, vector median filter, nonlinear filter, image (signal) processing, reconfigurable optical bus system.