Ericsson: HDR+ is the answer – and UHD needs to be re-positioned

By Barry Flynn, Contributing Editor

At the Connected TV Summit in London yesterday, Ericsson came as close to saying the consumer electronics industry had got UHDTV wrong as it was possible to – without actually saying so.

Earlier this month, Ericsson was talking up the possibility of an enhanced version of HD incorporating high dynamic range (HDR) as an alternative to UHD (see separate story).

But this week, Matthew Goldman, Senior Vice President Technology, TV Compression, at Ericsson, suggested that the very meaning of UHD as a term should be detached from the idea that it uses four times as many pixels as HD – and implied that UHD’s rollout could end up as a re-run of the 3DTV debacle if manufacturers and marketers failed to understand consumer’s viewing habits, or the role which HDR could play in delivering ‘immersiveness’.

The apparent toughening of Ericsson’s position comes as it launches a new industry body called the Ultra HD Forum in association with rival Harmonic and other major video players, with the aim of spearheading the educational process required.

This had its inaugural meeting at Ericsson’s Californian offices in Mountain View on June 9.  Significantly, its mission is “To stimulate consumer adoption of UHD and enhanced HD” (Editor’s italics).

Goldman’s reasoning is straightforward: consumers do not understand (because they haven’t been told) that to get the full ‘wow’ experience out of a display with four times the number of pixels as a standard HD set (‘4K’), they either need to double their existing screen size or halve the viewing distance.

“The rule of thumb [with HD] is approximately [..] three picture heights back from that screen is the proper viewing distance. If you sit much closer than that you see the pixels, if you sit much further than that you won’t see all the resolution in its full glory,” explains Goldman. But Ultra HD displays effectively halve that ‘rule’ to 1.5 picture heights as the ideal viewing distance.

 â€œIt’s not that [the manufacturers] are wrong: you really can see the difference in UHD,” concedes Goldman. “With a lot of the studies that are out there right now you see these new services that are being launched and it’s absolutely wonderful if you’re sitting at the right viewing distance for it. [But] what they didn’t count on was people being unwilling to change their viewing habits, to actually sit twice as close to the television in relation to the screen size.”

Resolving the problem can prove difficult in practice, Goldman points out. “If you want to maintain the current configuration of the furniture in your living-room and you own a 45-inch HD display, you need to buy an 85-inch UHD set [to get the desired effect].”

But Goldman argues that there are three other factors besides extra pixels that are equally immersive and do not require that viewers sit at the ‘proper’ viewing distance.

These work best in combination and include HDR, a wider colour gamut, and ten-bit sample precision, a bundle of features Goldman dubs ‘HDR+’. Ideally, these would run on 1080p HD displays using 50 or 60 fps instead of standard 1080i ones.

Ericsson demonstrated just such a set-up on its stand at this week’s  Connected TV Summit, running alongside an ordinary HD display showing the same sequences for comparison.

“Is it as good?,” Goldman asked. “Not really, if you’re sitting at the right viewing distance [..]. But if you’re not going to buy that larger display and you can’t see the spatial resolution, you won’t see any difference between these at all. You get all of the immersive ingredients but you don’t have the four-times spatial resolution – so this might be a way in the viewing environments that reflect most of the homes today that you could do that.”

Meanwhile, this ‘enhanced HD’ solution works on tablets and phones and it is much less expensive to deliver than UHD because it occupies less bandwidth and requires less storage. “It could be almost one-third of the bandwidth to use 1080p instead of 2160p [i.e. 4K UHD] – so it’s food for thought.”

Goldman believes he is beginning to get the HDR+ message across through the Ultra HD Forum. â€œWe have television manufacturers and representatives on the committee and they are getting it now and they are making changes to do with things like HDR – they’ve already increased the dynamic range in TVs coming out for the holiday season coming up,” he notes.

Meanwhile, TV display makers are also moving towards a wider colour gamut: “They’re not all the way there yet, but there’s a much higher colour response than they had before. And now they’re seriously looking at the 10-bit sample bit depths which they’d never even considered before, because all digital TVs have been eight-bit to date. But, of course, that means that there’s a few years of equipment that doesn’t have all these features in it.”

Ultimately, believes Goldman, the meaning of the term ‘UHD’ is going to have to be re-purposed or re-named by the marketers. “That is actually the focus that groups like the Ultra HD Forum are looking at. Right now the first thing you think of is that it’s four times the spatial resolution. And actually that shouldn’t be what you’re thinking about. You should be thinking about the immersive viewing experience.”

Asked why TV manufacturers didn’t start with ‘enhanced HD’ instead of going straight to 4K UHD, Goldman replied, “It’s what they could build and what they could sell. I think you’ll find that in many cases that is how the consumer electronics industry works. I need not remind anybody here about 3DTV.”