A method is provided for generating a output composite video data stream. During a first phase of a set of processing phases, a frame of first video data is received and then downscaled to produce a first block of data. Also during the first phase, the first block is stored and then retrieved from a...http://www.google.com/patents/US5455626?utm_source=gb-gplus-sharePatent US5455626 - Apparatus, systems and methods for providing multiple video data streams from a single source
