Institute of Informatics, Silesian University of Technology, Akademicka 16, Gliwice, 44-100 Poland.|Institute of Applied Computer Science, Lodz University of Technology, Al. Politechniki 11, 90-924 xc5x81xc3xb3dxc5xba, Poland and.|Department of Electrical Engineering, Stanford University, 350 Serra Mall, Stanford, CA, USA.|Department of Electrical Engineering, Stanford University, 350 Serra Mall, Stanford, CA, USA.|Department of Electrical Engineering, Stanford University, 350 Serra Mall, Stanford, CA, USA.