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. It is contrasted with the retroactively-named standard dynamic range (SDR). HDR changes the way the luminance and colors of videos and images are represented in the signal, and allows brighter and more detailed highlight representation, darker and more detailed shadows, and more intense colors.[1][2]
HDR allows compatible displays to receive a higher-quality image source. It does not improve a display's intrinsic properties (brightness, contrast, and color capabilities). Not all HDR displays have the same capabilities, and HDR content will look different depending on the display used, and the standards specify the required conversion depending on display capabilities.[3]
HDR-TV is a part of HDR imaging, an end-to-end process of increasing the dynamic range of images and videos from their capture and creation to their storage, distribution and display. Often, HDR is used with wide color gamut (WCG) technology. WCG increases the gamut and number of distinct colors available. HDR increases the range of luminance available for each color. HDR and WCG are separable but complementary technologies. Standards-compliant HDR display also has WCG capabilities, as mandated by Rec. 2100 and other common HDR specifications.
The use of HDR in television sets began in the late 2010s. By 2020, most high-end and mid-range TVs supported HDR, and some budget models did as well. HDR-TVs are now the standard for most new televisions.
There are a number of different HDR formats, including HDR10, HDR10+, Dolby Vision, and HLG. HDR10 is the most common format, and is supported by all HDR-TVs. Dolby Vision is a more advanced format that offers some additional features, such as scene-by-scene mastering. HDR10+ is a newer format that is similar to Dolby Vision, but is royalty-free. HLG is a broadcast HDR format that is used by some TV broadcasters.
History[edit]
2014[edit]
In January 2014, Dolby Laboratories announced Dolby Vision.[15]
In August 2014, PQ was standardized in SMPTE ST 2084.[128]
In October 2014, the HEVC specification incorporates code point for PQ.[129] Previously, it also incorporates the Main 10 profile that supports 10 bits per sample on their first version.[130]
In October 2014, SMPTE standardized the Mastering Display Color Volume (MDCV) static metadata in SMPTE ST 2086.[131]
2015[edit]
In March 2015, HLG was standardized in ARIB STD-B67.[132]
On 8 April 2015, The HDMI Forum released version 2.0a of the HDMI Specification to enable transmission of HDR. The specification references CEA-861.3, which in turn references SMPTE ST 2084 (the standard of PQ).[59] The previous HDMI 2.0 version already supported the Rec. 2020 color space.[133]
On 24 June 2015, Amazon Video was the first streaming service to offer HDR video using the HDR10 format.[134][135]
On 27 August 2015, Consumer Technology Association announced HDR10.[17]
On 17 November 2015, Vudu announced that they had started offering titles in Dolby Vision.[136]
2016[edit]
On 1 March 2016, the Blu-ray Disc Association released Ultra HD Blu-ray with mandatory support for HDR10 and optional support for Dolby Vision.[137]
On 9 April 2016, Netflix started offering both HDR10 and Dolby Vision.[138]
On June to September 2016, SMPTE standardized multiple dynamic metadata for HDR in SMPTE ST 2094.[139]
On 6 July 2016, the International Telecommunication Union (ITU) announced Rec. 2100, which defines the image parameters for HDR-TV and use two HDR transfer functions—HLG and PQ.[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.[140]
On 9 September 2016, Google announced Android TV 7.0, which supports Dolby Vision, HDR10, and HLG.[141][142]
On 26 September 2016, Roku announced that the Roku Premiere+ and Roku Ultra will support HDR using HDR10.[143]
On 7 November 2016, Google announced that YouTube would stream HDR videos that can be encoded with HLG or PQ.[144][145]
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.[146][147] The specification has been published as DVB Bluebook A157 and was published by the ETSI as TS 101 154 v2.3.1.[146][147]
2017[edit]
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.
On 20 April 2017, Samsung and Amazon announced HDR10+.[21]
On 12 September 2017, Apple announced the Apple TV 4K with support for HDR10 and Dolby Vision, and that the iTunes Store would sell and rent 4K HDR content.[148]
2020[edit]
On 13 October 2020, Apple announced the iPhone 12 and iPhone 12 Pro series, the first smartphone that can record and edit video in Dolby Vision directly from the camera roll.[149] iPhone uses the Dolby Vision profile 8.4 cross-compatible with HLG.[150]