An apparatus for efficiently performing spatial scalable compression of an input video stream is disclosed. A base encoder encodes a base encoder stream. Modifying means modifies content of the base encoder stream to create a plurality of base streams. An enhancement encoder encodes an enhancement encoder...http://www.google.com.tw/patents/US20050002458?utm_source=gb-gplus-share專利 US20050002458 - Spatial scalable compression
