Ultra HD Defined

FREMONT, CALIF.—“Ultra high definition” has been defined. The UHD Alliance this week released specifications for UHD, along with a logo identifying devices capable of displaying Ultra HD content.

The Alliance developed three specs that cover devices, distribution and content. All three require a resolution of at least 3840x2160 (not quite 4KTV); 10-bit color depth, BT.2020 color gamut and high dynamic range according to SMPTE ST 2084 EOTF.

There are two HDR spec options for displays: A combination of peak brightness and black level of either more than 1,000 nits peak brightness and less than 0.05 nits black level, or more than 540 nits peak brightness and less than 0.0005 nits black level. Devices also must display more than 90 percent of P3 colors to meet the requirements for the UHD Alliance logo. With regard to mastering, 100 percent of P3 colors must be displayed, and HDR is set at more than 1,000 nits brightness and less than 0.03 nits black level.

The specs focus on image quality and make no specific recommendation for immersive audio.

The year-old Alliance, comprised of 35 member companies (listed below), said that it has designated “multiple, independent centers around the globe to handle testing” to ensure compliance with the specs.

The UHDA specs and the associated licensing terms are available from the organization.

UHDA Member Companies
DirecTV
Dolby Laboratories
LG Electronics
Netflix
Panasonic
Samsung Electronics
Sony
Technicolor
The Walt Disney Studios
Twentieth Century Fox
Universal Pictures
Warner Bros. Entertainment
Amazon
ARRI
Dreamworks
DTS
Fraunhofer Gesellschaft
Hisense
HiSilicon Technologies
Intel
Koninklijke Philips N.V.
MStar Semiconductor
Nanosys Inc.
Novatek
NVIDIA
Orange
Realtek Semiconductor
Rogers Communications
Sharp
Shenzhen TCL New Technology
Sky U.K.
THX
Toshiba
TP Vision Europe B.V.