McCann's Law [after engineer and strategist Ken McCann] holds that the bit rate required to achieve broadcast quality video halves every 7 years. According to SMPTE Fellow David Wood, current chair of DVB groups in 3DTV and UHDTV, and past chair of the World Broadcasting Union Technical Committee, this pattern was born out in the developments of MPEG-2 and H.264 / AVC and is also coming true for HEVC.

“In two years time the work on the next-generation MPEG compression after HEVC will likely follow the same curve,” he predicted.

But this advance may not come quickly enough - or be good enough quality - for the needs of the mobile industry.

“It's great that MPEG is royalty free but I doubt the quality will match that of [a technology like] V-Nova,” said Thierry Fautier, VP video strategy Harmonic and president of the Ultra HD Forum in reference to Perseus a proprietary codec developed by V-Nova and which is gaining some traction in telco circles where it has been championed by cellular operator EE.

Matt Stagg, principal strategist at EE, said a recent trial using Perseus in crowded urban and thinly populated areas delivered “flawless” UHD signals at 6 Mbps. “We champion any innovation where we can see clear benefits to us and our customers,” he said.

Eric Achtmann, executive chairman of V-Nova, said broadcasters and operators already had a huge problem dealing with ever-increasing capacity demands.

“We recognise that current codec improvements are delivering a two-fold capacity improvement every five to seven years, but demand is growing at twenty-fold – and there’s a huge disconnect which needs addressing.”

He argued that the installed base of receivers has become too large to make any change practical or cost effective. “There are 2.6 billion smartphones in the market while 200 million payTV STB's are being deployed annually.” The installed base is growing and it would simply cost too much to upgrade all of them, he said.

In addition, said Achtmann, the industry's “unprecedented” investment in capacity cannot carry on. “The U.S. is investing $1 billion every 10 days in extra bandwidth capacity and upgrades,” he said. No matter how much money is thrown at the problem, he argued, that capacity will at some point be limited.

“So we need to work more intelligently with the capacity we have. It is clear that the next generation codec has to use existing infrastructure standards, use standard off the shelf hardware with the same packaging and transport, DRM and metadata that we currently use or at least be compatible with. And it has to be interoperable with the installed base of codecs.”

Naturally, V-Nova claims Perseus is all of these things. “Current codecs are reaching end of life. Incremental improvements will not suffice,” he said, calling for a paradigm shift.

Having barely got out the door with UHD-phase 1, the industry is demanding a better pixelled version, variously with Higher Frame Rates, Wider Color Gamut, Higher Dynamic Range and next-gen audio for which there are multiple contenders in each category attempting to pass through DVB, ATSC and SMPTE committees.

“There is too much technology and not enough convergence,” said Fautier. “We're living in a world where we can do all the encoding in software and decoders are programmable but this is not helpful [to the complexity].”

Plus, if all of the above attributes are wanted along with backwards compatibility to legacy hardware then the question is “how can you process the raw video without introducing anything you don't want?” he posed.

Fautier reckoned HDR UHD might be standardised by 2017 and the full range of attributes including HFR by 2020 earliest.

Ericsson also has a stake at the table, developing encoders/decoders which it licences. It made the point that there will be 13 times more video over mobile networks in 2020 than there was in 2014. Already half the traffic on mobile networks is video. By 2020 it will be more like 75%.

“When you understand that video spectrum is the most expensive spectrum on the planet you can see that compression is an area of huge focus for us,” said Tony Jones, Head of Technology, TV Compression, Ericsson.

More HD services, and progressively UHD services, will drain capacity, he said. “We have to deliver video efficiently using technologies like LTE broadcast and we also have to compress it well.”

Jones laid out the arguments that create the conditions to improve compression efficiency. These include continued competition among encoder vendors; “without that nothing happens,” he said. “If you have a monopolistic business you don't get innovation.” He pointed to the telco industry where voice codecs are specified and there's been little change.

“Wide adoption for wide scale of licensing makes R&D investment worthwhile,” he said. “And we need standards. Open standards are critical. It's important to know you can rely on it, that it's peer-reviewed and it will do what it says it does. Free licensing is a nice to have, of course, but free also inhibits the research investment.”

Wood pointed out that if a company takes part in bodies like MPEG, ISO or ITU then “no-one expects that you shouldn't be able to charge licence fees,” he said, “but the rule says you should apply fair, reasonable and non-discriminatory terms. The problem is that no-one has defined what the word 'reasonable' means in this case.”

This could create a field for lawyers as IP-patent holders argue over usage.

“There's no such thing as a free lunch,” said Achtmann. “When the cost of something critical goes to zero the investment drops. So the notion of saying 'free codec' and 'innovation' is a contradiction.” V-Nova has yet to reveal the cost for its licence.

Added Ericsson's Jones: “[codec development] is not a charity, it is a business.”