Rec. 2020

ITU-R Recommendation BT.2020, more commonly known by the abbreviations Rec. 2020 or BT.2020, defines various aspects of ultra-high-definition television (UHDTV) with standard dynamic range (SDR) and wide color gamut (WCG), including picture resolutions, frame rates with progressive scan, bit depths, color primaries, RGB and luma-chroma color representations, chroma subsamplings, and an opto-electronic transfer function.[1] The first version of Rec. 2020 was posted on the International Telecommunication Union (ITU) website on August 23, 2012, and two further editions have been published since then.[1][2][3][4][5] It is expanded in several ways by Rec. 2100.

CIExy1931 Rec 2020
CIE 1931 chromaticity diagram showing the Rec. 2020 (UHDTV) color space in the triangle and the location of the primary colors. Rec. 2020 uses Illuminant D65 for the white point.

Technical details

Resolution

Rec. 2020 defines two resolutions of 3840 × 2160 ("4K") and 7680 × 4320 ("8K").[1] These resolutions have an aspect ratio of 16:9 and use square pixels.[1]

Frame rate

Rec. 2020 specifies the following frame rates: 120p, 119.88p, 100p, 60p, 59.94p, 50p, 30p, 29.97p, 25p, 24p, 23.976p.[1] Only progressive scan frame rates are allowed.[1]

Digital representation

Rec. 2020 defines a bit depth of either 10-bits per sample or 12-bits per sample.[1]

10-bits per sample Rec. 2020 uses video levels where the black level is defined as code 64 and the nominal peak is defined as code 940.[1] Codes 0–3 and 1,020–1,023 are used for the timing reference.[1] Codes 4 through 63 provide video data below the black level while codes 941 through 1,019 provide video data above the nominal peak.[1]

12-bits per sample Rec. 2020 uses video levels where the black level is defined as code 256 and the nominal peak is defined as code 3760.[1] Codes 0–15 and 4,080–4,095 are used for the timing reference.[1] Codes 16 through 255 provide video data below the black level while codes 3,761 through 4,079 provide video data above the nominal peak.[1]

System colorimetry

RGB color space parameters[1]
Color space White point Primary colors
xW yW xR yR xG yG xB yB
ITU-R BT.2020 0.3127 0.3290 0.708 0.292 0.170 0.797 0.131 0.046

The Rec. 2020 (UHDTV/UHD-1/UHD-2) color space can reproduce colors that cannot be shown with the Rec. 709 (HDTV) color space.[6][7] The RGB primaries used by Rec. 2020 are equivalent to monochromatic light sources on the CIE 1931 spectral locus.[7][8] The wavelength of the Rec. 2020 primary colors is 630 nm for the red primary color, 532 nm for the green primary color, and 467 nm for the blue primary color.[8][9] In coverage of the CIE 1931 color space the Rec. 2020 color space covers 75.8%, the DCI-P3 digital cinema color space covers 53.6%, the Adobe RGB color space covers 52.1%, and the Rec. 709 color space covers 35.9%.[6]

During the development of the Rec. 2020 color space it was decided that it would use real colors, instead of imaginary colors, so that it would be possible to show the Rec. 2020 color space on a display without the need for conversion circuitry.[10] Since a larger color space increases the difference between colors an increase of 1-bit per sample is needed for Rec. 2020 to equal or exceed the color precision of Rec. 709.[10]

The NHK measured contrast sensitivity for the Rec. 2020 color space using Barten's equation which had previously been used to determine the bit depth for digital cinema.[6] 11-bits per sample for the Rec. 2020 color space is below the visual modulation threshold, the ability to discern a one value difference in luminance, for the entire luminance range.[6] The NHK is planning for their UHDTV system, Super Hi-Vision, to use 12-bits per sample RGB.[6][11]

Transfer characteristics

Rec. 2020 defines a nonlinear transfer function for gamma correction that is the same nonlinear transfer function that is used by Rec. 709, except that its parameters are given with higher precision:[1][12]

  • where E is the signal proportional to camera-input light intensity and E′ is the corresponding nonlinear signal
  • where α ≈ 1.09929682680944 and β ≈ 0.018053968510807 (values chosen to achieve a continuous function with a continuous slope)

The standard says that for practical purposes, the following values of α and β can be used:

  • α = 1.099 and β = 0.018 for 10-bits per sample system (the values given in Rec. 709)
  • α = 1.0993 and β = 0.0181 for 12-bits per sample system

While the Rec. 2020 transfer function can be used for encoding, it is expected that most productions will use a reference monitor that has an appearance of using Gamma 2.4 transfer function as defined in Rec. ITU-R BT.1886 and that the reference monitor will be evaluated as defined in Rec. ITU-R BT.2035.[1][13][14]

RGB and luma-chroma formats

Rec. 2020 allows for RGB and luma-chroma signal formats with 4:4:4 full-resolution sampling and luma-chroma signal formats with 4:2:2 and 4:2:0 chroma subsampling.[1] It supports two types of luma-chroma signals, called YCbCr and YcCbcCrc.

YCbCr may be used when the top priority is compatibility with existing SDTV and HDTV operating practices.[1][10] The luma (Y′) signal for YCbCr is calculated as the weighted average Y′ = KR⋅R′ + (1−KR−KB)⋅G′ + KB⋅B′, using the gamma-corrected RGB values (denoted R′G′B′) and the weighting coefficients KR = 0.2627, KG = 0.678 and KB = 0.0593.[1] As in similar schemes, the chroma components in YCbCr are calculated as C′B = 2⋅(B′−Y′)/(1−KB) and C′R = 2⋅(R′−Y′)/(1−KR), and for digital representation the Y′, C′B, and C′R signals are scaled, offset by constants, and rounded to integers.

The YcCbcCrc scheme is a "constant luminance" luma-chroma representation.[1] YcCbcCrc may be used when the top priority is the most accurate retention of luminance information.[1] The luma component in YcCbcCrc is calculated using the same coefficient values as for YCbCr, but it is calculated from linear RGB and then gamma corrected, rather than being calculated from gamma-corrected R′G′B′.[10] The chroma components in YcCbcCrc are calculated from the Y′, B′, and R′ signals with equations that depend on the range of values of B′−Y′ and R′−Y′.

Implementations

HDMI 2.0 supports the Rec. 2020 color space.[15] HDMI 2.0 can transmit 12-bit per sample RGB at a resolution of 2160p and a frame rate of 24/25/30 fps or it can transmit 12-bits per sample 4:2:2/4:2:0 YCbCr at a resolution of 2160p and a frame rate of 50/60 fps.[15]

The Rec. 2020 color space is supported by H.264/MPEG-4 AVC and H.265/High Efficiency Video Coding (HEVC).[16][17][18] The Main 10 profile in HEVC was added based on proposal JCTVC-K0109 which proposed that a 10-bit profile be added to HEVC for consumer applications.[19] The proposal stated that this was to allow for improved video quality and to support the Rec. 2020 color space that will be used by UHDTV.[19]

On September 11, 2013, ViXS Systems announced the XCode 6400 SoC which supports 4K resolution at 60 fps, the Main 10 profile of HEVC, and the Rec. 2020 color space.[20]

2014

On May 22, 2014, Nanosys announced that using a quantum dot enhancement film (QDEF) a current LCD TV was modified so that it could cover 91% of the Rec. 2020 color space.[21] Nanosys engineers believe that with improved LCD color filters it is possible to make a LCD that covers 97% of the Rec. 2020 color space.[21]

On September 4, 2014, Canon Inc. released a firmware upgrade, that added support for the Rec. 2020 color space, to their EOS C500 and EOS C500 PL camera models and their DP-V3010 4K display.[22][23]

On September 5, 2014, the Blu-ray Disc Association revealed that the future 4K Blu-ray Disc format will support 4K UHD (3840x2160 resolution) video at frame rates up to 60 frames per second.[24] The standard will encode videos under the High Efficiency Video Coding standard.[24] 4K Blu-ray Discs will support both a higher dynamic range by increasing the color depth to 10-bit per color, and a greater color gamut by using the Rec. 2020 color space.[24] The 4K-Blu-ray specification allows for three disc sizes, each with their own data rate: 50 GB with 82 Mbit/s, 66 GB with 108 Mbit/s, and 100 GB with 128 Mbit/s.[24] The first Ultra HD Blu-ray titles were officially released from four studios on March 1, 2016.[25]

On November 6, 2014, Google added support for the Rec. 2020 color space to VP9.[26]

On November 7, 2014, DivX developers announced that DivX265 version 1.4.21 has added support for the Main 10 profile of HEVC and the Rec. 2020 color space.[27]

On December 22, 2014, Avid Technology released an update for Media Composer that added support for 4K resolution, the Rec. 2020 color space, and a bit rate of up to 3,730 Mbit/s with the DNxHD codec.[28][29]

2015

On January 6, 2015, the MHL Consortium announced the release of the superMHL specification which will support 8K resolution at 120 fps, 48-bit video, the Rec. 2020 color space, high dynamic range support, a 32-pin reversible superMHL connector, and power charging of up to 40 watts.[30][31][32]

On January 7, 2015, Ateme added support for the Rec. 2020 color space to their TITAN File video platform.[33]

On March 18, 2015, Arri announced the SXT line of Arri Alexa cameras which will support Apple ProRes recording at 4K resolution and the Rec. 2020 color space.[34][35]

On April 8, 2015, Canon Inc. announced the DP-V2410 4K display and EOS C300 Mark II camera with support for the Rec. 2020 color space.[36][37]

On May 26, 2015, the NHK announced a 4K LCD with a laser diode backlight that covers 98% of the Rec. 2020 color space.[38][39] The NHK stated that at the time it was announced this 4K LCD has the widest color gamut of any display in the world.[40]

On June 17, 2015, Digital Projection International presented a 4K LED projector with support for the Rec. 2020 color space.[41]

2016

On January 4, 2016, the UHD Alliance announced their specifications for Ultra HD Premium which includes support for the Rec. 2020 color space.[42]

On January 27, 2016, VESA announced that DisplayPort version 1.4 will support the Rec. 2020 color space.[43]

On April 17, 2016, Sony presented a 55 in (140 cm) 4K OLED display with the support of Rec. 2020 color space.[44]

On April 18, 2016, the Ultra HD Forum announced industry guidelines for UHD Phase A which includes support for the Rec. 2020 color space.[45][46]

2017

At SID display week 2017, AUO displayed a 5" foldable 720p HD AMOLED display able to display 95% of the Rec. 2020 colorspace. Although 720p is not a resolution is not specified by Rec. 2020, the color space coverage is of note.

2018

At the 2018 Consumer Electronics Show, LG Display showcased the worlds first 8k OLED panel. Sony showcased an 8k LCD capable of displaying 10,000 nits of luminance, of note because the maximum luminance allowed by the PQ transfer function for HDR is 10,000 nits. HDMI 2.1 compatible chipsets were showcased and cables also are already commercially available, including 56G HDMI cables.

At SID display week 2018, various companies showcased displays that are able to cover over 90% of the Rec.2020 color space. JDI showcased an improvement of their 17.3" LCD 8k broadcast monitor that is powered by an RGB laser backlight system. This allows the display able to reproduce 97% of the Rec. 2020 color space.

Rec. 2100

Rec. 2100 is an ITU-R Recommendation released in July 2016 that defines high dynamic range (HDR) formats for both HDTV 1080p and 4K/8K UHDTV resolutions.[47] These formats use the same color primaries as Rec. 2020, but with different transfer functions for HDR use. Rec. 2100 includes two such transfer function definitions that may be used for HDR:[47][48]

The PQ scheme with 10 bits of color bit depth has also been called HDR10.[49] Similarly, the HLG scheme with 10 bits of color bit depth has been called HLG10.[45] The Ultra HD Forum guidelines for UHD Phase A include support for SDR formats with 10 bits of color bit depth based on both Rec. 709 and Rec. 2020 color gamuts and also both the HDR10 and HLG10 formats of Rec. 2100.[45]

In addition to defining RGB and YCbCr color representations that are the same as in Rec. 2020 except for the transfer functions, Rec. 2100 also defines a constant luminance scheme known as ICtCp. Rec. 2100 does not support the YcCbcCrc scheme of Rec. 2020.

See also

  • UHDTV – Digital video formats with resolutions of 4K (3840 × 2160) and 8K (7680 × 4320)
  • High Efficiency Video Coding (HEVC) – Video standard that supports 4K/8K UHDTV and resolutions up to 8192 × 4320
  • Rec. 709 – ITU-R Recommendation for HDTV
  • Rec. 601 – ITU-R Recommendation for SDTV
  • Rec. 2100 – ITU-R Recommendation for HDR HDTV and UHD

References

  1. ^ a b c d e f g h i j k l m n o p q r s t u "BT.2020: Parameter values for ultra-high definition television systems for production and international programme exchange". International Telecommunication Union. 2014-07-17. Retrieved 2014-08-31.
  2. ^ "BT.2020: Parameter values for ultra-high definition television systems for production and international programme exchange". International Telecommunication Union. 2012-08-23. Retrieved 2014-08-31.
  3. ^ "The international standard for Super Hi-Vision TV". NHK. 2012-08-23. Retrieved 2012-08-30.
  4. ^ "8K Ultra High Def TV Format Opens Options for TV Viewing". The Hollywood Reporter. 2012-08-28. Retrieved 2012-08-30.
  5. ^ "ITU approves NHK's Super Hi-Vision as 8K standard, sets the UHDTV ball rolling very slowly". Engadget. 2012-08-25. Retrieved 2012-08-30.
  6. ^ a b c d e ""Super Hi-Vision" as Next-Generation Television and Its Video Parameters". Information Display. Retrieved 2012-12-27.
  7. ^ a b "Super Hi-Vision format". NHK. Archived from the original on 2012-08-13. Retrieved 2012-08-24.
  8. ^ a b "Wide-color-gamut Super Hi-Vision System". NHK. Retrieved 2013-05-18.
  9. ^ David Wood (2012-03-08). "Deciding Tomorrow's Television Parameters" (PDF). European Broadcasting Union. Archived from the original (PDF) on 2014-01-08. Retrieved 2013-05-02.
  10. ^ a b c d "BT.2246-2(2012): The present state of ultra-high definition television". International Telecommunication Union. 2013-01-16. Retrieved 2013-04-30.
  11. ^ "Super Hi-Vision Production Devices for Mobile". NHK. Retrieved 2013-05-18.
  12. ^ "BT.709: Parameter values for the HDTV standards for production and international programme exchange". International Telecommunication Union. 2009-08-27. Retrieved 2012-09-15.
  13. ^ "BT.1886: Reference electro-optical transfer function for flat panel displays used in HDTV studio production". International Telecommunication Union. 2011-04-06. Retrieved 2014-08-31.
  14. ^ "BT.2035: A reference viewing environment for evaluation of HDTV program material or completed programmes". International Telecommunication Union. 2013-08-13. Retrieved 2014-11-05.
  15. ^ a b "FAQ for HDMI 2.0". HDMI.org. Retrieved 2014-01-25.
  16. ^ "H.264: Advanced video coding for generic audiovisual services". ITU. 2013-06-07. Retrieved 2013-06-16.
  17. ^ G.J. Sullivan; J.-R. Ohm; W.-J. Han; T. Wiegand (2012-05-25). "Overview of the High Efficiency Video Coding (HEVC) Standard" (PDF). IEEE Transactions on Circuits and Systems for Video Technology. Retrieved 2013-06-16.
  18. ^ "H.265: High efficiency video coding". ITU. 2013-06-12. Retrieved 2013-06-16.
  19. ^ a b Alberto Dueñas; Adam Malamy (2012-10-18). "On a 10-bit consumer-oriented profile in High Efficiency Video Coding (HEVC)". JCT-VC. Retrieved 2013-06-16.
  20. ^ "ViXS Announces XCode 6400, the World's First System-on-Chip (SoC) with Native Support for 10-bit High Efficiency Video Coding (HEVC) and Ultra High Definition (HD) 4K". PRNewswire. 2013-09-11. Retrieved 2013-09-15.
  21. ^ a b "Is the rec.2020 UHD color broadcast spec really practical?". Nanosys. 2014-05-22. Retrieved 2014-07-21.
  22. ^ "Free Canon Firmware for Cinema EOS System Cameras Delivers Improved Basic Performance, Including Support for ITU-R BT.2020 Color Space". MarketWatch. September 4, 2014. Retrieved September 6, 2014.
  23. ^ "Free Canon Firmware Upgrade for DP-V3010 30-Inch 4K Professional Display Enables Confirmation of ITU-R BT.2020 Color Gamut Video Content". Business Wire. September 4, 2014. Retrieved September 6, 2014.
  24. ^ a b c d "4K Blu-ray discs arriving in 2015 to fight streaming media". CNET. September 5, 2014. Retrieved October 18, 2014.
  25. ^ "Upcoming Fox 4K Blu-ray Titles". Retrieved January 12, 2016.
  26. ^ "Change the use of a reserved color space entry". Chromium (web browser). Google. 2014-11-06. Retrieved 2014-11-07.
  27. ^ "DivX HEVC Community Encoder" (Press release). DivX. 2014-11-04. Retrieved 2014-11-15.
  28. ^ Wim Van den Broeck (2014-12-22). "Editing 4K and Beyond in Media Composer Now Available with Avid Resolution Independence Update". Avid Technology. Retrieved 2014-12-23.
  29. ^ Bryant Frazer (2014-12-22). "Starting Today, You Can Finally Edit 4K Natively in the Avid". studiodaily. Retrieved 2014-12-23.
  30. ^ "MHL Consortium Announces superMHL – the First Audio/Video Specification With Support Up to 8K". Yahoo Finance. 2015-01-06. Archived from the original on 2015-10-20. Retrieved 2015-01-10.
  31. ^ Ryan Smith (2015-01-06). "MHL Consortium Announces superMHL: New Standard & New Cable To Drive 8K TV". AnandTech. Retrieved 2015-01-10.
  32. ^ "Introducing superMHL". MHL. Retrieved 2015-01-10.
  33. ^ "High Fidelity Pixels Enhance Ultra HD Video On Demand". PR Newswire. 2015-01-07. Retrieved 2015-01-10.
  34. ^ Deborah D. McAdams (2015-03-18). "Arri Rolls Out Alexa With 4K ProRes Recording". TVTechnology. Retrieved 2015-03-19.
  35. ^ "ALEXA SXT". Arri. Archived from the original on 2015-03-20. Retrieved 2015-03-19.
  36. ^ Jose Antunes (2015-04-08). "New 24-inch 4K Reference Display from Canon". Pro Video Coalition. Retrieved 2015-04-08.
  37. ^ Jose Antunes (2015-04-08). "The EOS C300 Mark II Has Arrived". Pro Video Coalition. Retrieved 2015-04-08.
  38. ^ "NHK Showcases Latest 8K Super Hi-Vision Technologies". cdrinfo. 2015-05-26. Retrieved 2015-05-26.
  39. ^ "Laser-backlit Wide-gamut LCD and Color Gamut Mapping". NHK. Retrieved 2015-05-26.
  40. ^ Tetsuo Nozawa (2015-06-01). "STRL Announces 4k Display With World's Widest Color Gamut". Nikkei Business Publications. Retrieved 2015-06-01.
  41. ^ "Digital Projection Launches World's Brightest LED Projector at InfoComm" (Press release). AVNetwork. June 16, 2015. Retrieved May 8, 2016.
  42. ^ "UHD Alliance Defines Premium Home Entertainment Experience". Business Wire. 2016-01-04. Retrieved 2016-01-13.
  43. ^ "VESA Updates Display Stream Compression Standard to Support New Applications and Richer Display Content". PRNewswire. 2016-01-27. Retrieved 2016-01-29.
  44. ^ "Sony introduces the PVM-X550, a 55" quad-view large screen Trimaster EL 4K OLED monitor" (Press release). Sony. 2016-04-17. Retrieved 2016-05-08.
  45. ^ a b c "End-to-end guidelines for phase A implementation". Ultra HD Forum. 2016-04-18. Retrieved 2016-04-18.
  46. ^ "Ultra HD Forum Releases First Industry Guidelines for Deploying End-to-End Live & Pre-Recorded UHD Services in 2016". Business Wire. 2016-04-18. Retrieved 2016-04-18.
  47. ^ a b "BT.2100: Image parameter values for high dynamic range television for use in production and international programme exchange". International Telecommunication Union. 2016-07-04. Retrieved 2016-07-04.
  48. ^ Adam Wilt (2014-02-20). "HPA Tech Retreat 2014 – Day 4". DV Info Net. Retrieved 2014-11-01.
  49. ^ Rachel Cericola (2015-08-27). "What Makes a TV HDR-Compatible? The CEA Sets Guidelines". Big Picture Big Sound. Retrieved 2015-09-21.

External links

1080p

1080p (1920×1080 px; also known as Full HD or FHD and BT.709) is a set of HDTV high-definition video modes characterized by 1,920 pixels displayed across the screen horizontally and 1,080 pixels down the screen vertically; the p stands for progressive scan, i.e. non-interlaced. The term usually assumes a widescreen aspect ratio of 16:9, implying a resolution of 2.1 megapixels. It is often marketed as full HD, to contrast 1080p with 720p resolution screens.

1080p video signals are supported by ATSC standards in the United States and DVB standards in Europe. Applications of the 1080p standard include television broadcasts, Blu-ray Discs, smartphones, Internet content such as YouTube videos and Netflix TV shows and movies, consumer-grade televisions and projectors, computer monitors and video game consoles. Small camcorders, smartphones and digital cameras can capture still and moving images in 1080p resolution.

16K resolution

The term 16K resolution (8640p) refers to a display resolution that has 15360 horizontal pixels by 8640 vertical pixels, for a total of 132.7 megapixels. It has four times as many pixels as 8K resolution, sixteen times as many pixels as 4K resolution and sixty-four times as many pixels as 1080p resolution.

Innolux's 100-inch 16K8K S-UHD (15360×8640) display module displayed at Touch Taiwan is the only single display as of August 2018.Currently 16k resolutions can run on Multi-monitor setups with AMD Eyefinity or NVIDIA Surround.

2K resolution

2K resolution is a generic term for display devices or content having horizontal resolution of approximately 2,000 pixels. Digital Cinema Initiatives (DCI) defines 2K resolution standard as 2048×1080.In the movie projection industry, DCI is the dominant standard for 2K output.

4K resolution

4K resolution, also called 4K, refers to a horizontal display resolution of approximately 4,000 pixels. Digital television and digital cinematography commonly use several different 4K resolutions. In television and consumer media, 3840 × 2160 (4K UHD) is the dominant 4K standard. In the movie projection industry, 4096 × 2160 (DCI 4K) is the dominant 4K standard.

The 4K television market share increased as prices fell dramatically during 2014 and 2015. By 2020, more than half of U.S. households are expected to have 4K-capable TVs, a much faster adoption rate than that of Full HD (1080p).

Academy Color Encoding System

The Academy Color Encoding System (ACES) is a color image encoding system created by hundreds of industry professionals under the auspices of the Academy of Motion Picture Arts and Sciences. ACES allows for a fully encompassing color accurate workflow, with "seamless interchange of high quality motion picture images regardless of source".The system defines its own color primaries that completely encompass the visible spectral locus as defined by the CIE xyY specification. The white point is approximate to the CIE D60 standard illuminant, and ACES compliant files are encoded in 16-bit half-floats, thus allowing ACES OpenEXR files to encode 30 stops of scene information. ACES supports both high dynamic range (HDR) and wide color gamut (WCG).The version 1.0 release occurred in December 2014, and has been implemented by multiple vendors, and used on multiple motion pictures and television shows. ACES received a Television Academy Emmy Engineering Award in 2012. The system is standardized in part by the Society of Motion Picture and Television Engineers (SMPTE) standards body. Changes in the ACES specifications, announcements, news, discussion and other information is regularly updated at http://www.ACESCentral.com.

Hundreds of productions, from Motion Pictures to Television to Commercials, and VR content has been produced using ACES including:

The Lego Batman Movie (2017)

Guardians of the Galaxy Vol. 2 (2017)

King Arthur: Legend of the Sword (2017)

The Grand Tour (2016 TV Series)

Cafe Society (2016)

Bad Santa 2 (2016)

The Legend of Tarzan (2016)

Chef's Table (2016 TV Series)

Chappie (2015)

The Wedding Ringer (2015)

Baahubali: The Beginning (2015)

The Wave (2015)

For a more complete list, visit the IMDb link here: http://acescentral.com/t/list-of-aces-productions/23

Avid DNxHD

Avid DNxHD ("Digital Nonlinear Extensible High Definition") is a lossy high-definition video post-production codec developed by Avid for multi-generation compositing with reduced storage and bandwidth requirements. It is an implementation of SMPTE VC-3 standard.

Dolby Laboratories

Dolby Laboratories, Inc. (often shortened to Dolby Labs and known simply as Dolby) is an American company specializing in audio noise reduction and audio encoding/compression. Dolby licenses its technologies to consumer electronics manufacturers.

HCL color space

HCL (Hue-Chroma-Luminance) is a color space model designed to accord with human perception of color. HCL has been adopted by information visualization practitioners to present data without the bias implicit in using varying saturation.

High-dynamic-range video

High-dynamic-range video (HDR video) describes video having a dynamic range greater than that of standard-dynamic-range video (SDR video).Key characteristics of HDR video are brighter whites, deeper blacks, and at least a 10-bit color depth (compared to 8-bit for SDR video) in order to maintain precision across this extended range.

While technically distinct, the term "HDR video" is commonly understood to imply wide color gamut as well.

High Efficiency Video Coding

High Efficiency Video Coding (HEVC), also known as H.265 and MPEG-H Part 2, is a video compression standard, one of several potential successors to the widely used AVC (H.264 or MPEG-4 Part 10). In comparison to AVC, HEVC offers about double the data compression ratio at the same level of video quality, or substantially improved video quality at the same bit rate. It supports resolutions up to 8192×4320, including 8K UHD.

List of RAL colors

Below is a list of RAL Classic colors from the RAL colour standard. The CIE L*a*b* and RGB Web colors shown are approximate and informative only.

Ostwald color system

In colorimetry, the Ostwald color system is a color space that was invented by Wilhelm Ostwald. Associated with the Color Harmony Manual, it comprises a set of paint chips representing the Ostwald color space. There are 4 different editions of the Color Harmony Manual. Each manual is made up of charts, with each chart being a different color space.

RG color space

The RG or red-green color space is a color space that uses only two colors, red and green. It is an additive format, similar to the RGB color model but without a blue channel. Thus, blue is said to be out of gamut. This format is not in use today, and was only used on two-color Technicolor and other early color processes for films; by comparison to a full spectrum, its poor color reproduction made it undesirable. The system cannot create white naturally, and many colors are distorted.

Rec. 2100

ITU-R Recommendation BT.2100, more commonly known by the abbreviations Rec. 2100 or BT.2100, defines various aspects of high dynamic range (HDR) video such as display resolution (HDTV and UHDTV), frame rate, chroma subsampling, bit depth, color space, and optical transfer function. It was posted on the International Telecommunication Union (ITU) website on July 4, 2016. Rec. 2100 expands on several aspects of Rec. 2020.

Rec. 601

ITU-R Recommendation BT.601, more commonly known by the abbreviations Rec. 601 or BT.601 (or its former name, CCIR 601) is a standard originally issued in 1982 by the CCIR (an organization which has since been renamed as the International Telecommunication Union – Radiocommunication sector) for encoding interlaced analog video signals in digital video form. It includes methods of encoding 525-line 60 Hz and 625-line 50 Hz signals, both with an active region covering 720 luminance samples and 360 chrominance samples per line. The color encoding system is known as YCbCr 4:2:2.

The Rec. 601 video raster format has been re-used in a number of later standards, including the ISO/IEC MPEG and ITU-T H.26x compressed formats – although compressed formats for consumer applications usually use chroma subsampling reduced from the 4:2:2 sampling specified in Rec. 601 to 4:2:0.

The standard has been revised several times in its history. Its edition 7, referred to as BT.601-7, was approved in March 2011 and was formally published in October 2011.

Ultra-high-definition television

Ultra-high-definition television (also known as Ultra HD television, Ultra HD, UHDTV, UHD and Super Hi-Vision) today includes 4K UHD and 8K UHD, which are two digital video formats with an aspect ratio of 16:9. These were first proposed by NHK Science & Technology Research Laboratories and later defined and approved by the International Telecommunication Union (ITU).The Consumer Electronics Association announced on October 17, 2012, that "Ultra High Definition", or "Ultra HD", would be used for displays that have an aspect ratio of 16:9 or wider and at least one digital input capable of carrying and presenting native video at a minimum resolution of 3840×2160 pixels. In 2015, the Ultra HD Forum was created to bring together the end-to-end video production ecosystem to ensure interoperability and produce industry guidelines so that adoption of ultra-high-definition television could accelerate. From just 30 in Q3 2015, the forum published a list up to 55 commercial services available around the world offering 4K resolution.The "UHD Alliance", an industry consortium of content creators, distributors, and hardware manufacturers, announced during a Consumer Electronics Show (CES) 2016 press conference its "Ultra HD Premium" specification, which defines resolution, bit depth, color gamut, high-dynamic-range imaging (HDRI) and rendering (HDRR) required for Ultra HD (UHDTV) content and displays to carry their Ultra HD Premium logo.

Ultra HD Blu-ray

Ultra HD Blu-ray is a digital optical disc data storage format that supersedes Blu-ray. Ultra HD Blu-ray discs are incompatible with existing Blu-ray players. Ultra HD Blu-ray supports 4K UHD (3840 × 2160 resolution) video at frame rates up to 60 frames per second, encoded using High Efficiency Video Coding. The discs support both high dynamic range by increasing the color depth to 10-bit per color and a greater color gamut than supported by conventional Blu-ray video by using the Rec. 2020 color space.

Ultra HD Forum

Ultra HD Forum is an organization whose goal is to help solve the real world hurdles in deploying Ultra HD video and thus to help promote UHD deployment. The Ultra HD Forum will help navigate amongst the standards related to high dynamic range (HDR), high frame rate (HFR), next generation audio (NGA), and wide color gamut (WCG). The Ultra HD Forum is an industry organisation that is complementary to the UHD Alliance (that maintains consumer-facing logos), covering different aspects of the UHD ecosystem.

White point

A white point (often referred to as reference white or target white in technical documents) is a set of tristimulus values or chromaticity coordinates that serve to define the color "white" in image capture, encoding, or reproduction. Depending on the application, different definitions of white are needed to give acceptable results. For example, photographs taken indoors may be lit by incandescent lights, which are relatively orange compared to daylight. Defining "white" as daylight will give unacceptable results when attempting to color-correct a photograph taken with incandescent lighting.

This page is based on a Wikipedia article written by authors (here).
Text is available under the CC BY-SA 3.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.