A lapped-orthogonal-transform based variable bit-rate video coder for packet networks

The future broadband integrated services digital network must be capable of carrying packetized high-quality conventional TV and high-definition TV signals to make its deployment successful. In order to accomplish this, robust packet video coding techniques and strategies must be developed that deliver high quality pictures even in the case of significant packet loss. The authors describe a lapped-orthogonal-transform (LOT) based variable-bit-rate coder that is a strong contender for this application. The overlapping nature of the LOT allows the coder to partially reconstruct a block of pixels from its neighboring blocks during packet loss. The coder's performance as affected by packet length, packet prioritization method, and lost packet recovery technique is evaluated, verifying the effectiveness of the approach.<>