SMPTE ST 2056:2011

This Standard defines a standardized wrapper for the carriage of low bit rate MPEG-2 TS packets, in the 10-bit vertical ancillary data (VANC) space of a standard definition or high definition serial digital link in accordance with SMPTE ST 291. Examples of such low bitrate services are EBIF and DVB bitmapped subtitles.

Note: Low bit rate means typically 1-20 TS packets per video frame.