4K/8K Video

Video Industry Finally Defines 4K

As promised earlier this year, the UHD Alliance (UHDA) has published a specification that spells out the minimum requirements of what qualifies as ultra-high definition and has arranged to have testing labs around the world certify UHD products that meet those qualifications. (See UHD Alliance Aims for Early-2016 Release.)

UHD, a.k.a. 4K TV, has been around for more than a decade. But companies involved with the production, editing, distribution and display of UHD have not always agreed with each other on minimum requirements for the many characteristics of UHD video, which include not just resolution but also color bit depth, color palette, dynamic range and more.

The new UHD spec dictates minimum video characteristics and makes recommendations for audio as well. Companies that produce products that meet the standards can license a new logo from the UHDA. The organization has also created a new category of participation -- Adopters -- for companies that are interested simply in getting their products certified.

Want to know more about ultra HD? Check out our video channel here on Light Reading.

The UHDA's spec is broken into three categories, one each for device's (currently, television displays, with other devices under consideration) distribution and content. Image resolution in all cases must be at least 3840 x 2160.

The device category includes the following specifications:

  • Color bit depth: 10-bit signal
  • Color palette/wide color gamut (signal input: BT.2020 color representation; display reproduction: more than 90% of p3 colors)
  • High dynamic range (SMPTE ST2084 EOTF; a combination of peak brightness and black level)

Any distribution channel delivering the UHD Alliance content must support:

  • Color bit depth: minimum 10-bit signal
  • Color: BT.2020 color representation
  • High dynamic range: SMPTE ST2084 EOTF

The UHD Alliance Content Master must meet the following requirements:

  • Color bit depth: minimum 10-bit signal
  • Color: BT.2020 color representation
  • High dynamic range: SMPTE ST2084 EOTF

The UHD Alliance recommends the following mastering display specifications:

  • Display reproduction: minimum 100% of P3 colors
  • Peak brightness: more than 1000 nits
  • Black level: less than 0.03 nits

The UHDA said the specs were developed in concert with film studios, consumer electronics manufacturers, content distributors and technology companies.

UHDA members include DirecTV, Dolby Laboratories Inc. (NYSE: DLB), LG Electronics Inc. (London: LGLD; Korea: 6657.KS) , Netflix Inc. (Nasdaq: NFLX), Panasonic Corp. (NYSE: PC), Samsung Corp. , Sony Corp. (NYSE: SNE), Technicolor (Euronext Paris: TCH; NYSE: TCH), Walt Disney Co. (NYSE: DIS), 20th Century Fox , NBC Universal , Warner Bros. Entertainment Inc. , Amazon.com Inc. (Nasdaq: AMZN), Arris Group Inc. (Nasdaq: ARRS), DreamWorks LLC , Intel Corp. (Nasdaq: INTC), Nvidia Corp. (Nasdaq: NVDA), Orange (NYSE: FTE), Koninklijke Philips Electronics N.V. , Rogers Communications Inc. (Toronto: RCI), Sharp Electronics Corp. , complink 813|British Sky Broadcasting Group plc}, Toshiba Corp. (Tokyo: 6502) and others.

"The diverse group of UHDA companies agreed that to realize the full potential of Ultra HD, the specs need to go beyond resolution and address enhancements like HDR, expanded color and ultimately even immersive audio. Consumer testing confirmed this," said UHD Alliance President Hanno Basse. "The criteria established by this broad cross section of the Ultra HD ecosystem enables the delivery of a revolutionary in-home experience, and the Ultra HD Premium logo gives consumers a single, identifying mark to seek out so they can purchase with confidence."

— Brian Santo, Senior Editor, Components, T&M, Light Reading

kq4ym 1/18/2016 | 10:52:04 AM
Re: Pontential It seems the industry in on the right road now to get those standards agreed upon and more importantly perhap to do the tests. Allowing to "testing labs around the world certify UHD products" is going to keep everyone honest and get consumers more comfortable with just what products are supposed to do and the level of performance for those as yet way expensive sets.
inkstainedwretch 1/5/2016 | 8:18:56 PM
Re: Pontential The basic standards were in place. What was lacking was agreement on what the baseline values would be for common characteristics, such as dynamic range. The industry could create and distribute 4K video for people to enjoy without these specs; the issue was whether the visual quality would vary -- and it probably would have otherwise. -- Brian Santo
danielcawrey 1/5/2016 | 8:04:23 PM
Pontential I believe 4K has potential as a consumer technology. But standards are always important. It's surprising to me that it has taken 10 years for these standards to be adopted. At the same time, now that there is consumer promise, there is motivation to get something like this done. 
Sign In