High-dynamic-range television

High-dynamic-range television (HDR-TV) is a technology that uses high dynamic range (HDR) to improve the quality of display signals.

[4] Standard dynamic range (SDR) is still based on and limited by the characteristics of older cathode-ray tubes (CRTs), despite the huge advances in screen and display technologies since CRT's obsolescence.

HDR contents are often limited to a peak brightness of 1,000 or 4,000 nits and P3-D65 colors, even if they are stored in formats capable of more.

No current display is able to reproduce the maximal range of brightness and colors that can be represented in HDR formats.

[6] Other HDR formats, such as HDR10 and hybrid log–gamma (HLG), do not offer this possibility, so the content creator's intents are not ensured to be preserved on less capable displays.

[6] The dynamic metadata are used to improve image quality on limited displays that are not capable of reproducing an HDR video to its fullest intended extent.

[16] The HDR10 Media Profile, more commonly known as HDR10, is an open HDR standard announced on 27 August 2015 by the Consumer Technology Association.

[6] The metadata is static and constant with respect to each individual video and does not inform the display exactly how the content should be adjusted.

[10] Dolby Vision is an end-to-end ecosystem for HDR video, and covers content creation, distribution, and playback.

[6] Dolby Vision certification requires displays for content creators to have a peak luminance of at least 1,000 nits.

[66] The DisplayHDR standard from VESA is an attempt to make the differences in HDR specifications easier for consumers to understand.

2100 is a technical recommendation by ITU-R for production and distribution of HDR content using 1080p or UHD resolution, 10-bit or 12-bit color, HLG or PQ transfer functions, full or limited range, the Rec.

[11][73] SDR uses a gamma curve transfer function that is based on CRT characteristics and is used to represent luminance levels up to around 100 nits.

[1] HDR uses newly developed PQ or HLG transfer functions instead of the traditional gamma curve.

[6][8] Because of the increased dynamic range, HDR contents need to use more bit depth than SDR to avoid banding.

[45] Coding-independent code points (CICP) are used to signal the transfer function, color primaries and matrix coefficients.

[24] It is carried in HEVC SEI, ETSI TS 103 433, CTA 861-G.[97] Core components of DMCVT are defined in SMPTE ST 2094-1.

[45] ETSI GS CCM 001 describes a Compound Content Management functionality for a dual-layer HDR system, including MMR (multivariate multiple regression) and NLQ (non-linear quantization).

[99] UHD Phase A defines HDR as having a dynamic range of at least 13 stops (213=8192:1) and WCG as a color gamut that is wider than Rec.

[104] W3C added HDR support to PNG using cICP, abandoning ICC PQ profile method.

Apple: iPhone 12 and later support the aforementioned "gain map" HDR technique for still images.

[113] Captured HDR pictures can also be converted to SDR JPEG (sRGB color space) and then viewed on any standard display.

[116] Google: Android 14 and later support the aforementioned "Ultra HDR" gain map technique for still images.

[117][83] A plug-in allowing the editing of HLG stills (HSP) in Photoshop CC has been released by Panasonic.

[118][119] The company also released a plug-in for displaying thumbnails of those HDR images on a PC (for Windows Explorer and macOS Finder).

[119] Qualcomm: Snapdragon 888 mobile SoC allows the capture of 10-bit HDR HEIF still photos.

[11][73] On 29 July 2016, SKY Perfect JSAT Group announced that on 4 October, they would start the world's first 4K HDR broadcasts using HLG.

[145] On 7 November 2016, Google announced that YouTube would stream HDR videos that can be encoded with HLG or PQ.

[146][147] On 17 November 2016, the Digital Video Broadcasting (DVB) Steering Board approved UHD-1 Phase 2 with a HDR solution that supports HLG and PQ.

[148][149] On 2 January 2017, LG Electronics USA announced that all of LG's SUPER UHD TV models support a variety of HDR technologies, including Dolby Vision, HDR10, and HLG (Hybrid Log Gamma), and are ready to support Advanced HDR by Technicolor.