Faculty of Electronics and Information Technology of Warsaw University of Technology, Institute of Computer Science, Nowowiejska 15/19, Warsaw, 00-665, Poland. T.Gambin@ii.pw.edu.pl|Faculty of Electronics and Information Technology of Warsaw University of Technology, Institute of Computer Science, Nowowiejska 15/19, Warsaw, 00-665, Poland. T.Gambin@ii.pw.edu.pl