Apparatus and method for digital advertisement insertion in bitstream

摘要

A system for inserting commercials into an audiovisual bit stream by providing cue commands in response to cue tones in a pre-existing analog signal, and/or in response to control signals from an uplink (/programmer/network) site or headend (/affiliate). Firmware upgrades are provided to a digital encoder to facilitate generating spliceable bit streams and generation of cue_commands. This enables commercial insertion at an uplink site (/programmer/network) as well as at a cable television headend (/affiliate). The system provides functional compatibility between a digital bit stream and the analog cue tones. The cue commands are preferably carried in the transport layer of the bit stream so there is no need to decode and process several layers of the bit stream. Accordingly, a new commercial insertion capability can be added to existing uplink and headend equipment in a backward compatible manner minimizing upgrade-related expenses, yet allowing different splicing techniques to be employed depending on cost-performance tradeoffs in terms of desired post-splicing audiovisual quality.