Since the DVB specification for ultra high definition (UHD) TV, UHD-1 Phase 2, was approved at the end of 2016, global rollout has been slow but unspectacular. Digital TV Europe’s assessment, based on a range of expert contributions, is that as gaps across the supply chain are plugged, 2018 should herald a significant uplift in UHD services.
Peter Siebert, DVB executive director, admits the format has had a slower start by comparison to the move from SD to HD. “Many UHD channel launches are playing out loops of pre-recorded material; not what I regard as UHD programming,” he says. “But this is an evolution, not a big bang, and follows the normal investment and upgrade cycle for consumers and broadcasters.”
Thomas Wrede, vice-president, new technology and standards, media Platforms at satellite operator SES offers a more upbeat perspective. “We see a real acceleration of Ultra HD – by 2025, analysts expect over 700 UHD channels globally. In fact, UHD is growing so fast that it is outpacing HD development, if you compare their respective rollout globally: UHD started with 13 channels on its first year of commercialisation and grew to 92 two years later [by year-end 2017], while HD went from 13 channels to 32 in the same time-frame.”
Rian Bester, CEO at Insight TV, the UHD factual-entertainment channel says: “There’s a definite acceleration in rollout and adoption to which Phase 2 has contributed. The enhancements brought by HDR [High Dynamic Range], WGC [Wide Color Gamut] and HFR [High Frame Rate] are blatantly obvious and undeniable. But would I call it a ‘tipping point’? Not totally.”
David Mercer, director at Strategy Analytics believes that the UHD rollout is “a little behind schedule compared to what many were hoping a year or so ago” but concurs that momentum is building again. “We would be surprised if most major platforms were not carrying at least some UHD services by the end of this year.”
A recent IABM survey indicated that 35% of broadcasters would launch a UHD service in the next three years; 59% said they would roll out within a decade.
In addition, the ATSC 3.0 standard will advance UHD deployments outside of DVB territories beginning in Korea and then the US. ATSC 3.0 is designed to deliver 4K UHD and immersive audio with the increased payload capacity combined with HEVC encoding.
Widening content gap
The take-up of UHD TVs is obviously a critical indicator for broadcasters. Strategy Analytics estimates that 176 million UHD TVs were in use worldwide by the end of 2017. Household penetration had reached 19% in North America and 14% in Western Europe.
“These data-points are helping to persuade many broadcasters that they have to start considering their own plans for UHD very seriously,” says Mercer.
By comparison, Futuresource Consulting reported worldwide penetration of 8% at end of 2017, which by 2021 is expected to increase to 71% of sales and 29% penetration. Shipments of UHD streaming devices – Roku, Apple etc. – are rising too. At the end of 2017 they comprised about eight million or 36% of all units sold. “We have moved beyond the phase of early adoption of UHD and are now in the strong growth phase,” says Futuresource’s Tristan Veale.
If UHD has had a sluggish start, most pundits pin the blame on costs incurred in higher bandwidth and increases in capital expenditure.
“Broadcasters need to be convinced of the business case for the extra cost in studio infrastructure when many PSBs are financially still digesting HD,” says Siebert. “I’m convinced UHD will come but it will follow normal investment cycles, except where there’s an opportunity to move to build greenfield [operations].”
The media industry is always in a state of transition: analogue to digital, SD to HD, and now SDI to IP-based production infrastructure, as well shifting from HD to UHD formats.
“These transitions are time-consuming and expensive, which leads to a classic chicken and egg situation,” says Insight’s Bester. “We have stores full of UHD TVs and consumers that want to purchase them but not enough content to warrant the expense.”
Futuresource attributes the widening gap between sales of 4K-ready consumer hardware and content to the expense of contribution and distribution: “Most operators see little incentive to shorten replacement lifecycles in order to provide 4K UHD STBs to consumers,” says Veale. As it stands, marketing from hardware manufacturers “is the most important factor in upgrading customers to 4K capable devices”, says Veale, rather than a desire for UHD content.
There is little holding back 4K UHD production, with Bester claiming its cost has been “overstated” since 2014. “If you simply applied the same inefficient HD workflow to UHD, the cost difference can be significant, but through efficient and smart workflow adaptions, the cost increment can be minimised,” he says. “Camera development, storage pricing and more competition in the post production space has squeezed the incremental variance even further.”
Futuresource points to a significant quantity of content that is being recorded and produced in UHD, but not immediately being made available to consumers. Rather, content production is being ‘future-proofed’ for later UHD launches.
“The gap between hardware and content availability exists because providers need to be convinced of the commercial benefits of making their content available in the higher-definition format,” says Globecast’s UK managing director Samuel Lemercier. “This is not happening overnight.”
There’s little in the way of premium value in 4K to be squeezed from the consumer. Competition among SVOD streamers has actually lowered the price of 4K UHD content. Apple meanwhile doesn’t differentiate in price between its 4K and HD titles on iTunes, forcing Amazon and Google to remove or reduce the differential for their resolution-specific tiers.
Yet content is deemed “critically important” by Tim Felstead, director of strategic and operational marketing at technology provider Rohde & Schwarz, and “a necessity” by Leonid Berkovich, vice-president of marketing at Viaccess-Orca. “With 4K content available, the entire business can be rolled out,” says Berkovich.
The pressure to create more content is however dampened by the available outlet channels, a factor that Felstead links to the reluctance of media companies to allocate the bandwidth required for UHD.
“Broadcasters must invest in UHD at multiple points, with this investment currently not being matched by the financial return from customers,” Felstead says. “As such, the upgrades and content acquisition are challenging for many operators that are seeing increasingly suppressed margins.”
Even the Winter Olympics featured limited 4K production by comparison with the 4,000 hours – including 860 live hours – it produced in HD. Matters may change this summer when FIFA and production partner Sony produce all matches from the World Cup in Russia in 4K HDR, although how many free-to-air public and commercial rights holders like the BBC and ITV will launch a UHD service, even temporarily, for viewers is unclear.
Of course, in addition to bandwidth-hungry 4K resolution, the UHD-1 Phase 2 spec caters for the introduction of additional audio-visual features, the most significant being HDR, which delivers a bigger visual punch than added pixel count.
Telestream’s vice-president of product management, media workflow and production solutions, Scott Murray’s take is typical: “4K is not necessarily a driver, especially when the images are so compressed. What will drive widespread adoption is not more pixels but HDR.”
The industry typically uses the term ‘HDR’ to refer to the combination of three image technologies and not the HDR transfer function alone: HDR plus Wide Colour Gamut (WCG) plus 10-bit sample bit depth.
HDR techniques can be applied with “visually stunning results”, says Felstead, to all resolutions and frame rates.
However, there has been no clear agreement on the ‘best’ HDR solution to use. As was apparent at CES, TV manufacturers have clearly anticipated that a winner from the format war will not emerge anytime soon, and are insuring themselves by offering all manner of formats in their latest display lines.
The good news is that there’s near universal agreement that the HDR10 and HLG formats are must-haves, with Dolby Vision a strong third place. Samsung is a notable abstainer with regards to Dolby Vision. Philips/Technicolor’s HDR technology also has supporters – LG for one. The DVB for its part has ratified HLG and PQ10 (from which HDR10 is derived) in UHD Phase 2.
To clarify further, Dolby also had a hand in developing PQ (Perceptual Quantization) and derived its 12-bit solution from it. Veale says: “This can be delivered in such a way that if a device has a 10-bit display then it will seamlessly show at the fullest capabilities of the display. However, if the panel is 12-bit and the company licenses the Dolby Vision product then it will show Dolby Vision in all its glory.”
Devised by NHK and the BBC, allowing backward compatibility with SDR displays, it’s no surprise that HLG is emerging as the front-runner in Europe and Japan for traditional live/linear services. Recent announcements from AT&T/DirecTV add weight to Strategy Analytics’ prediction that HLG will become the de facto distribution standard in broadcast.
“The absence of metadata simplifies the entire broadcast chain especially for live events and scene-referred technology will not need re-mastering for different display types,” says Felstead of HLG.
However, it is the dynamic metadata of Dolby Vision and the metadata extension to HDR10 (HDR10+) that makes these formats more suitable for on-demand content and services. Originally developed by Samsung as an alternative to paying Dolby a licence, royalty-free HDR10+ has the backing of Fox and Warner Bros (along with Panasonic).
Most, if not all, online services use different HDR technologies simultaneously. For example, Netflix has content available in HDR10 and Dolby Vision. Amazon, Wuaki.tv, iTunes, YouTube, Sony’s Ultra Streaming Service, Sony Playstation, Google Play Movies & TV, Vudu, UltraFlix, Fandango, Xbox one and Playstation 4 are all offering a few – but not necessarily all – of the various technologies.
“Once the specifications settle down we will see a standard set available across the whole spectrum of UHD 4K video viewing services online,” predicts Nagra’s product marketing chief Anthony Smith-Chaigneau. “Standards have reached a milestone where quality is at a level required with new standards taking backward compatibility as a main requirement. For example, HDR10+ is now used by Amazon services and is backwards compatible with HDR10 devices.”
Amazon auto show, The Grand Tour
Indeed, Amazon’s entire library of HDR content on Amazon Prime, including The Grand Tour, is now available in the HDR10+ standard, and can be viewed on 2017 UHD Samsung televisions.
Further standards convergence is likely. Over time, Futuresource predicts HLG will likely be phased out in favour of PQ10. “The developers of HLG themselves admitted that it is a stopgap to streamline the switch over to HDR,” says Veale. “Many TVs and AV hardware use a transfer function to convert a HLG stream to PQ10 anyway as displays more commonly support this correctly.”
HD HDR services are likely to appear too, says Veale, “particularly for broadcasters with bandwidth constraints, such as terrestrial broadcasters or those distributing via IPTV that are able to apply some ABR [adaptive bitrates].”
In spite of the success of early non-HDR UHD services – notably those of Sky and BT in the UK – it’s clear that the debate around HDR has contributed to the uncertainty many broadcasters feel about deploying UHD services.
EBU senior executive Dr Hans Hoffman has criticised industry players for “being short-sighted in the belief that pushing individual HDR solutions will drive market adoption more quickly and to their own benefit”. He believes that investments and new service rollouts will remain on hold until the industry stabilises.
Smith-Chaigneau meanwhile reports that some operators launching UHD services are opting to go without HDR “because the quality was still not entirely satisfactory”. “They still want to fine tune the end-to-end chain to make sure they deliver a clear difference compared to the HD equivalent,” he says.
Mercer confirms this. “Many broadcasters are reluctant to commit to UHD until there’s greater clarity on which HDR standards will be adopted, and until uncertainty over technical issues in workflow and distribution has been eliminated,” he says. However, he adds, “Sooner or later broadcasters will come under pressure from competitors, not just in TV but in OTT and even 4K Blu-ray, to make their move towards 4K and HDR.”
Currently, the technology is ready for end-to-end UHD HDR. There are production, encoding and networking delivery technologies for broadcast and unicast, as well as decoder equipment and TVs able to process 4Kp60 in HDR10 and HLG10 with some channel-based Next-Gen Audio.
The ‘full fat UHD experience’ of NGA, HFR and WCG is likely to play a secondary role in the perception of most consumers at this stage, but equipment manufacturers are nevertheless positioning themselves to differentiate their hardware.
WCG (BT.2020) “is the natural next step of competition between TV hardware manufacturers once they have exhausted their attempts to promote HDR,” suggests Veale. “Implementation in conjunction with HDR is already in train but broadcasters are largely dependent on content producers and the consumer’s AV set-up for the quality of WCG their customers receive.”
With regard to Higher Frame Rate, “the issue becomes one of economy with media[companies needing to estimate if HFR will bring them ROI”, says Felstead. “Temporal resolution is a fine goal for certain types of media like sport, but it is only one element and not currently a high priority in the minds of our customers.”
Next generation audio (NGA) meanwhile seems to be getting the least priority and attention, but Bester believes this will rapidly change during 2018. NGA implementation has already begun; BT Sport and Sky have adopted Dolby Atmos. “The audio experience is incredibly important,” agrees Peter Sellar, associate director, broadcast, at the UK’s Digital Television Group. “NGA provides other advantages through the ability to personalise the experience, or tailor for accessibility.”
Insight TV is evaluating NGA and says the possibilities of applying it to content are promising for various reasons, “ranging from providing specific audio for the hearing impaired to adding additional audio per scene. The engagement for our viewers can be greatly increased,” says Bester.
The key issue here is that broadcasters are totally reliant on the consumer’s audio set-up. As a way round this, Futuresource notes that some broadcasters are offering relatively low-priced set-top boxes integrated into a soundbar.
HFR would seem to be an easier transition, since there are only two main choices: 100Hz or 120Hz. In reality, says Hoffman of the EBU, a number of questions are still unresolved: “Will consumer electronics devices apply simple or more sophisticated frame rate conversion algorithms, or will they depend on a true higher frame rate broadcast signal? And what about interfaces such as HDMI to carry HFR signals?”
While cinema appears stuck on 24 frames per second for theatrical exhibition, rates of 50/60fps are realistic for TV today. TV drama and theatrical will likely remain at 24/25fps for editorial reasons but higher frame rates can enhance the quality sports, which could ultimately benefit from the maximum of 120fps.
Insight has been natively shooting and producing 50fps video since 2014 but Bester says the upper limits of the UHD spec are not yet practical. “100/120fps are just found in test content as camera, post-production and broadcast chains and even displays are still catching up,” he says.
Unlike HDR and WCG the (double or triple) increase in bits required for HFR needs to be taken into account. HFR-suitable mezzanine compression systems are an option, but they will require standardisation and add complexity in the production chain.
Smith-Chaigneau says, “Devices have to handle very large amounts of data in their circuitry and this raises many challenges. Additionally, in distribution, backwards compatibility issues with legacy standard frame rate [SFR] systems need to be solved.”
These cost factors “means the market isn’t going to see any dramatic uptake of HFR in the foreseeable future,” says Lemercier.
The downside of all these twists and turns in the development of UHD will be the inevitable confusion and incompatibility issues experienced by consumers. Even Samsung’s marketing team appeared confused when in a tweet from IFA2017 they claimed HDR10+ as superior to HDR+, Samsung’s own proprietary SDR-to-HDR upconversion algorithm.
Futuresource reports that consumer awareness of HDR has “barely grown” over the last two years and remains at 40% in the US and closer to 20% in Europe and developed APAC countries. Veale says: “From an idealistic view it shouldn’t be marketed as HDR. It should be an intrinsic part of the UHD development as was originally intended, and therefore not a monetisable element. The improvement of UHD resolution over HD isn’t that significant but when HDR, WGC and NGA are included as standard, then it becomes a much more attractive proposition and one which will be a significant improvement of quality when consumers do upgrade.”
Telestream’s Murray calls the whole alphabet soup a “muddle”, while VO’s Berkovich says that “operators have ideas about how to monetise HDR, but it’s hard to project how much viewers are willing to pay for this service.”
The availability of suitable broadband connections could also have an impact on consumer perceptions. Some 34 million households worldwide have a 4K TV and access to an SVOD package with UHD content. “Most of these would have watched UHD content at some point this way. However, due to broadband limitations, most wouldn’t consistently stream in UHD,” says Veale.
“Early adopters will be frustrated by the older inadequacies of their equipment or may not realise it’s not performing as desired,” says Smith-Chaigneau. “Many consumers will have to make their own assumption, and clearly learn that higher quality means higher bandwidth requirements. It is a safe assumption that UHD still requires at least 16Mbps of bandwidth to be considered good enough quality.”
The quest for the perfect picture is by no means over. It will no doubt carry on for many years to come, driven by the desire to bring true-to-life images into the home.
Will content providers and distributors go further? The prospect of 8K broadcasts is currently disregarded by nearly every contributor to this piece. Bester’s view is typical: “With 4K UHD content still relatively scarce and only really starting to drive mass market awareness and adoption now, I simply cannot see 8K on the near horizon. I simply don’t see it as feasible nor desirable in this decade.”