[1] Technion Israel Inst Technol, Viterbi Fac Elect Engn, IL-3200003 Haifa, Israel
[2] Cornell Univ, Dept Comp Sci, Ann S Bowers Coll Comp & Informat Sci, Ithaca, NY 14850 USA
[3] Hebrew Univ Jerusalem, Dept Appl Phys, Fac Sci, IL-91904 Jerusalem, Israel
[4] Adobe Res, San Jose, CA 95110 USA
[5] Kyoto Univ, Dept Intelligence Sci & Technol, Kyoto 6068501, Japan