DVB is ‘centre stage` in the discussion on UHDTV delivery standards. The DVB UHD-1 Phase 1 specification was agreed several years ago, and the Phase 2 specification, which includes additional features, is now in preparation - slated for completion later in 2016. The DVB annual conference, DVB World in March 2016, naturally looked underneath the stones for several key UHDTV issues.
One is whether UHDTV is a solution to a problem – or is it a solution in search of a problem? The hypothesis put forward was that the most benefit from UHDTV would come from stadium sports` events. If so, we may ask, what does this imply about the features we need to include in UHD-1 Phase 2?
Another issue is whether the possibly pending plurality of options (the ‘tool box’) in the specification for audio (NGA) and for high dynamic range (HDR) is more favourable or less favourable for UHDTV delivery. Having multiple options could be a headache for broadcasters and set makers, but at the same time it could also bring manufacturer competition that could be beneficial. Which is the heavier side of the scales?
A further issue is the relative timelines for UHDTV content and UHDTV TV sets. Up until now, with UHD Phase 1, the synchronisation has not been perfect. Will it be better in the Phase 2 age after 2017?
Reflecting on specifics, the HDR situation is not crystal clear at the moment. ITU-R has prepared a draft new Recommendation with only two of the candidate systems in it (the US PQ system ST 2084 and the BBC/NHK LG system) - but whether this means other proposed systems are no longer in the game is not known. Just before DVB World, there was a MPEG meeting which concluded that in HDR there was no more work for them to be done, bearing in mind that the HEVC system, as it is, would allow any of the systems to be used. Where does this leave the standard? What will DVB decide for the Phase 2 specification later in the year?
Without prejudging the DVB conclusions, it may be telling that during DVB World, in answer to a question, one set maker said that their UHDTV HDR sets could be made to decode both ITU-R HDR system options. Will this will be eventual outcome for all HDR sets?
There are two options for the ‘next generation audio’ system on the table – the Dolby system and the MPEG-H system. One of the main debates here is about the internal system in the receiver that converts the received ‘audio elements` into loudspeaker feeds – this is the receiver ‘renderer’. Is this something for which there should be a reference renderer specified, so broadcasters can judge better what the viewer may hear, or should the renderer be left to the set maker and to competition to create ever better renderers? The answer you get depends on whom you ask.
The next DVB World will be DVB Asia in Thailand in the autumn. Will some of these issues be resolved by then?