A video transmitter identifies regions in pictures in a compressed three-dimensional video comprising a base view video and an enhancement view video. Means for Solving Problems A substrate for immobilizing a biopolymer, which has a mask layer provided with multiple through-holes at predetermined positions on a flat active face, is brought into contact with a solution containing a chain-type biopolymer. A pair of vertical deflecting coils are toroidally wound around the core. The atomizer is connected to a gas inlet and a sample inlet. The present invention also relates to a process for preparing these aqueous copolymer dispersions and to their use in coating compositions.