The EBU UHDTV strategy group has updated the EBU Exchange Parameters for UHD/HDR* programmes, both for live (EBU R 153) and file-based content (EBU R 154). The new versions are based on recent work from contributing EBU Members and are designed to be easier to use. Related work on distribution of subtitles has resulted in an update to another recommendation, EBU R 110.
Right from the outset of the UHD/HDR exchange parameters work, in 2021, it was agreed that the two recommendations would be updated based on operational feedback. Under the leadership of Karl Petermichl (ORF), this task was recently completed by specialists from several EBU Members.
What has changed?
The main changes for the live recommendation include the reference to the single-master HDR production workflow, as described in EBU Technical Report 070, the use of eight audio channels for channel-based audio production, and reference to EBU-TT/IMSC instead of EBU STL if subtitling is provided.
The file-based exchange parameters now recommend the use of XAVC MXF (or IMF where multiple versions are required), and the use of EBU-TT-D (EBU Tech 3380) for any subtitling. Readability of the audio section has been improved by clearly outlining two options: A) conventional audio, and B) metadata-guided audio.
The updated EBU recommendations are to facilitate content exchange between EBU Members, other broadcasters, service providers and production companies. The guidance is meant as a ‘safe starting point’, for use when no other agreements between two parties for UHDTV programme exchange are in place.
Subtitle distribution
While EBU R 153 and 154 focus on contribution, related work was recently completed by the EBU Timed Text group on distribution aspects of subtitling. An update to EBU R 110 means that it now recommends the use of IMSC Text Profile / EBU-TT-D to ensure compliance with the subtitling technology used on various distribution platforms (DVB-TTML, HbbTV, and DVB-DASH).
* High dynamic range