US Patent 7848364 Exploitation of null packets in packetized digital television systems

A system and method for adding auxiliary data DA to an output data stream from a statistical multiplexer is disclosed. An auxiliary multiplexer accepts a statistically multiplexed data stream, and substitutes auxiliary data packets for null data packets. The auxiliary multiplexer controls the number of null packets in the statistically multiplexed data stream by controlling the target bandwidth BT of the statistical multiplexer, or by modifying the statistical multiplexer equation to make the auxiliary data stream a participant in the negotiation process of allocating throughput among the data sources.