HDR Explained: Become an Expert in 4K HDR Before Clients Demand It

Joel Silver, president and founder of the Imaging Science Foundation, on why HDR and wide color gamut technologies will help all types of users.


The consumer electronics industry wants it, but according to one of the video industry’s most well-known video experts, the commercial market needs it.

The “it” is high dynamic range (HDR), a technology that transforms 4K Ultra HD from a marketing tool to legitimate game changer, according to Joel Silver, president and founder of the Imaging Science Foundation (ISF).

The trials and tribulations of both the consumer and commercial cinema video markets are well known. For a short time 3D sparked an interest in large HDTVs, and it spurred premium pricing for select 3D movie showings. But 3D-driven interest was short lived.

Moving quickly, both the residential and commercial markets set their sights on Ultra HD/4K resolution.

A recent report from IHS Inc., found that despite a 4 percent drop in overall TV shipments in 2015, 4K TV shipments rose 173 percent.

And with the increasing availability of 4K content and the development of HDR-enabled projectors and displays, these technologies are refueling video sales.

HDR: The State of Confusion

In an interview with CE Pro sister publication Commercial Integrator, Stijn Henderickx, VP of digital cinema for Barco, noted that HDR creates whiter whites, deeper blacks, and an “appropriate rendering between the signal and display.”

Henderickx said it is important the industry standardize HDR formats so the public sees movies the way directors and cinematographers intend. However, Silver says that at this point a single standard is not as important as the possibilities and innovations that open standards could deliver.

“I don’t want a standard for HDR,” he states. “The UHD Alliance and HDMI aren’t restricting us to our standards. Open architecture thanks to HDMI brings us innovation. So now when I see Technicolor, Philips, Dolby and the BBC talking about open-format HDR, it will make it better. HDMI 2.0a opens the door to the gamma of HDR10. The Vizio products are Dolby Vision but not HDR10. We can overlay HDR; the question is will video purists want it? I say no, because I am modifying the color the producers of the movies intended. Hopefully we will follow the audio community and become as successful as they have been with the different surround-sound formats.”

It is important to note that there are several groups, including companies mentioned by Silver, that are pushing their own specifications. Ultimately the goal is to develop displays that reproduce the BT.2020 color gamut space, and high levels of dynamic range. The consumer market and bodies such as the Consumer Technology Association (formerly the Consumer Electronics Association) and UHD Alliance have defined Ultra HD/4K standards that include provisions for HDR. Other components include the ability to deliver high frame rates (HFRs), and also falling under the specs umbrella are requirements for audio.

The CTA-issued “HDR Compatible Display” guideline states products must comply with EOTF (electro-optical transfer function) SMPTE ST 2084, while also providing color sub-sampling 4:2:0 for compressed video sources; 10-bit color; and the ITU-R BT.2020 color gamut.

To achieve certification displays must also comply with the Blu-ray Disc Association’s (BDA) HDR10 spec, which the CTA has also adopted. Part of this requires LED displays to produce peak brightness levels of 1,000 nits. (Silver says the use of “nits” could be confusing for those more familiar with “foot-lamberts,” and explains that nits are a measurement of the equivalent of one candela per square meter.)

The UHD Alliance’s specification, which includes the awarding of its Premium Logo, requires a resolution of 3840 x 2160 with a 10-bit color depth and BT.2020 wide color gamut input signal representation, and the display to reproduce 90 percent of the P3 spectrum. The Alliance’s HDR requirements include a combination either of greater than 1,000 nits peak brightness and less than 0.05 nits black level, or greater than 540 nits peak brightness and less than 0.005 nits black level. The Dolby Vision format requires even higher levels of brightness, with 4,000 nits of luminance.

But regardless of whether the video industry moves ahead with a single 4K HDR format or chooses to allow for open standards, experts agree that consumer and commercial markets only stand to benefit.

Many Market Applications

When discussing HDR’s potential for both residential and commercial installers, Silver says HDR just grabs attention. He notes that in marketing and advertising applications, for instance, 4K with HDR’s high levels of contrast and richness of colors stands out against SD and HD digital signage displays. He adds that the technology can aid professionals who rely upon video in critical applications to do their jobs better. And regardless of the application, Silver says, its effect is something that even non-videophiles will notice.

“In commercial applications I can put four documents in 1080p on a 4K screen. On the consumer side, we need a better picture to the untrained eye. The best of Blu-ray and sports are pretty good; when we launch 4K properly, [viewers] will see HDR and wide color gamut from across the room,” he says. “It is big news. It is demonstrably superior to the untrained eye, and they will say, ‘I will buy it.’ … It takes a lot to see the [greater] resolution; it doesn’t take talent to see the color gamut.”

Applications that will benefit from HDR include digital cinema, digital signage, training and simulation, medical, education and public venues such as museums. High-profile companies such as Sony, Christie Digital, Digital Projection (DP), Epson and Barco all offer a growing selection of products with an increasing amount of these solutions incorporating HDR to address this potential.

Sony recently introduced what could be a very impactful solution: end-to-end, complete 4K systems aimed at medical applications. Sony’s Professional Solutions America division’s new system includes a 4K medical recorder, 4K content management system, 4K source-to-IP converters, 4K camera systems, and 4K displays.

The company says it developed this line with options for high-contrast ratios in well-lit rooms, and it includes features such as water-resistant enclosures, minimal-glare screens, and simplified wiring connections.

Christie’s collaboration with Dolby to co-develop, supply, install and service Dolby Vision projection systems represents another imaging improvement for end users to notice; imagine the possibilities beyond cinemas, for example, into museums and theme parks. Doug Darrow, senior vice president cinema, Dolby Laboratories, notes these systems will match the bold brightness levels and vivid color spectrum that human eyes can see, and the high-frame rate 6P laser light engine products, are also capable of producing high-contrast images that meets the specifications of filmmakers.

“Dolby Cinema lets studios and exhibitors focus on what they do best, with the confidence that Dolby will deliver a premium experience that makes the most of the latest cinema technologies,” explains Darrow. “I’m pleased that we were able to work with Christie to co-develop the Dolby Vision projection system.”

Silver adds that one thing integrators need to consider with all of the talk of expanded color gamuts, HDR and Ultra HD, is that even though most current products don’t meet the brightness and wide color gamut specifications, the increases in performance that have been already brought to market through compliance with the P3 color gamut  spec are already making a big performance difference. In the near future, he says, projectors and displays will meet these standards.

Before the market reaches these levels of brightness and color gamut capabilities, Silver says dealers will eventually refer to such specs in a streamlined, but descriptive term of “color volume.” He explains: “If you look at a projector or display’s capability for performance, and how many colors can it make and how bright it is, you will state it as color volume. Color volume is a 3D view of the CIE [chromacity] chart. Our three parameters of how much color, how bright it is, and how black it is with HDR is way beyond what we can buy.

“With consumer video we can get close to professional monitors,” he continues. “Today a high-end Dolby monitor produces 10,000 nits, an affordable monitor produces 4,000 nits, and a TV at home produces about 900 nits. So that content has to be toned down or mapped.”

Silver cautions that one catch for integrators will be the onus to become experts in the displays and applications.

“Dealers will have to know their products better,” he says. “LED video walls are more capable than consumer models. They are HDR right now. Some of the signage market is there too. HDR is a great tool for signage. Content creation has taken a leap that will open the door for innovation.”

About the Author

Robert Archer
Robert Archer:

Bob is an audio enthusiast who has written about consumer electronics for various publications within Massachusetts before joining the staff of CE Pro in 2000. Bob is THX Level I certified, and he's also taken classes from the Imaging Science Foundation (ISF) and Home Acoustics Alliance (HAA). Bob also serves as the technology editor for CE Pro's sister publication Commercial Integrator. In addition, he's studied guitar and music theory at Sarrin Music Studios in Wakefield, Mass., and he also studies Kyokushin karate at 5 Dragons and Brazilian jiu-jitsu at Binda Brazilian Jiu Jitsu; both schools are located in Haverhill, Mass.




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