Elementary Flows for Live IP Production

Live Internet Protocol (IP) flows promise significant benefits in enhancing media-processing flexibility in the broadcast plant. Existing serial digital interface (SDI) formats in use today carry a multiplex of active video, ancillary data, and embedded audio over 75Ω coaxial cable. Although SMPTE ST 2022-6 encapsulates this entire SDI multiplex signal using IP, it is unclear if this is the optimal payload format for a networked broadcast plant. A large amount of wasted space exists within the ancillary area of an SDI signal. Also, system flexibility can be enhanced by placing video, audio, and ancillary data into elementary flows that can be individually and independently switched at the network layer, without the penalty of demultiplexing or remultiplexing the SDI signal. This paper describes a recommendation for the carriage of elementary media flows for live IP production, including mechanisms to describe the logical relationships between these elementary flows for composition and synchronization.