Amendment 1 to ITU-T H.222.0 (2014) | ISO/IEC 13818-1 (201x) (5th edition) enables signaling and synchronization of external enhancements of programs carried over a MPEG-2 Transport Stream (TS). Specifically, it enables transport of a media timeline in an MPEG-2 TS program, in order to provide a stable media timeline not sensitive to PCR discontinuities; it also enables signaling of the location of current and potentially upcoming external media enhancements. The technologies included in this amendment can be used to locate and synchronize external content with an MPEG 2 TS program, regardless of the external content packaging or coding types; to accommodate the different application use cases, the signaling information and the timing information may be sent at different frequencies. In order to provide frame-accurate timeline alignments, despite potential PCR discontinuities that typically occur in an MPEG-2 TS network, different types of time codes can be inserted into the TS. The information can be sent in a dedicated PES stream identified in the program's PMT, for cases where bandwidth requirements are not too constrained, or can be inserted in the adaptation field of the media PID when the overhead of sending one TS packet per time code would be too high. For example, the typical bitrates for time code signaling for each frame of a 60 Hz video is around 90 kbit/s using PES only carriage and between 4 and 7 kbit/s using adaptation field scheme.