The platform operator for digital terrestrial TV said in a response to Ofcom's consultation on the future use of the UHF TV frequency band: "it is difficult to see how a further market-led platform development at this stage could be possible within the likely clearance timescale."
HEVC (High Efficiency Video Coding) would allow more channels to fit on each digital terrestrial television multiplex, with more room for HD channels, and even next generation 4K services*. HEVC would solve the problem of how to retain a competitive number of channels on Freeview using less frequencies. However Digital UK is concerned that it wouldn't be possible to provide a transition period between the currently used MPEG2/MPEG4 video standard to HEVC if Ofcom clears another batch of frequencies for 5G from 2018. A transition would be required as current Freeview and Freeview HD receivers are not compatible with HEVC.
According to the consultation response, Ofcom "will need to consider that any future move toward a HEVC standard would require sufficient spectrum to be made available for DTT use to facilitate MPEG2 or MPEG4/HEVC simulcasting. In that respect, it is hard to envisage how such a transition could be possible were anything less than 470-694 MHz made exclusively available for broadcasting and auxiliary services." At the moment, other services such as PMSE and White Space Devices are scheduled to share the same frequency band with TV at the proposed time of clearance.
So if HEVC was to be introduced in the future, full clearance of more frequencies for 5G mobile could only realistically begin once a transition period with simulcasting, giving time for households to move over to the new standard (reminiscent of the 625 line and 405 line black and white TV simulcasts of the late 1960s to early 1980s), had been completed.
With an eye on the cost of future changes, Digital UK also told the regulator that "it is difficult for multiplex operators to manage and monetise these sorts of technical transformations whilst still maintaining the low cost universal access to its services that is required by Government policy, the respective multiplex licences and the BBC Charter."
Incidentally, Samsung Electronics has stated that any move to HEVC on Freeview should only be made when one of the following milestones is met:
- The Introduction and transition to Ultra HD services
- The integration of HEVC in DTT receivers is systematic and a high number of households are sufficiently equipped.
* A 2012 Zetacast report for Ofcom predicted that it would be possible to broadcast 8 x 1080p HD channels in HEVC per multiplex by 2020 or 17 x 720p channels in HEVC.