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Dolby Vision

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Dolby Vision
Websitehttps://www.dolby.com/technologies/dolby-vision/ Edit this on Wikidata

Dolby Vision is a set of technologies developed by Dolby Laboratories for high dynamic range (HDR) video.[1][2][3] It covers content creation, distribution, and playback.[1][4][5][6] It includes dynamic metadata that are used to adjust and optimize each frame of the HDR video to the consumer display's capabilities in a way that replicates the content creator's intention.

Dolby Vision was introduced in 2014,[1][7][8] making it the first available HDR format. HDR10+ is a competitor HDR format that also uses dynamic metadata.[9]

Dolby Vision IQ is an update designed to optimize Dolby Vision content according to the ambient light.[10]

Dolby Cinema uses Dolby Vision too; it uses 108 nits, compared to SDR cinemas' use of 48 nits and 2.6 gamma.[11]

Description

Dolby Vision allows for a maximum resolution of 8k up to 12-bit color depth, maximum peak brightness of 10,000 nits.[12] However, according to the Dolby Vision white paper, as of 2018 professional reference monitors, such as the Dolby Vision HDR reference monitor, are currently limited to 4,000 nits of peak brightness.[13]

Dolby Vision includes the PQ transfer function, a wide-gamut color space (ITU-R Rec. BT.2020 in YCBCR or IPTPQc2), up to 8K resolution, and for some profiles (FEL) up to 12-bit. It can encode mastering display colorimetry information using static metadata (SMPTE ST 2086) and also provide dynamic metadata (SMPTE ST 2094-10, Dolby format) for each scene or frame.[14] This dynamic metadata or Dynamic HDR allows adjusting of brightness and contrast (in reality, the tone curve) on the scene by scene or even frame by frame bases as and when required and adjusts it many times during the video/movie.[citation needed] It is considered to be future-proof.[15]

Dolby Vision includes dynamic metadata that are used to adjust the brightness, color and sharpness[citation needed] of each frame of the video to match the display color volume (i.e. the maximum and minimum brightness capability and the color gamut).[16][2][17] It allows for the creative intents to be preserved on all Dolby Vision compatible displays. Dolby Vision and HDR10+ do not use the same dynamic metadata.

Technical details

The Dolby Vision format is capable of representing videos with a peak brightness up to 10,000 cd/m2 and a color gamut up to Rec. 2020.[17] Current displays cannot reproduce the full Dolby Vision brightness and gamut capability. There are no brightness and color gamut capability requirements for consumer displays. When the consumer display has lower color volume than the mastering display, the content is adjusted to the consumer display capability based on the dynamic metadata.

Dolby Vision mastering display require:[18]

  • EOTF: PQ
  • Peak brightness: at least 1,000 cd/m2
  • Black level: at most 0.005 cd/m2
  • Contrast ratio: at least 200,000:1
  • Color gamut: at least 99% of P3

Metadata

Dolby Vision metadata include:[16]

  • L0 (static): Mastering and target display characteristics
  • L1 (dynamic): Automatically generated
  • L2 trims (dynamic): Manually generated per frame or per scene
  • L3 trims (dynamic): Manually generated per frame or per scene (since CMv4.0)
  • L8 trims (dynamic): Manually generated per frame or per scene (since CMv4.0) (equivalent of L2 trims)
  • L5: Timeline aspect ratio description
  • L6 (static and optional): MaxCLL and MaxFALL (required for HDR10)
  • L9 (dynamic): Mastering display color primaries (since CMv4.0)

Dolby Vision 4.0 introduces new secondary trims for hue and saturation adjustment.[19]

Profiles

Dolby Vision profiles[20][21]
Profile Codec BL:EL resolution Backward compatibility
4 10-bit HEVC 1:1/4 SDR
5 10-bit HEVC No enhancement layer None

(It uses proprietary IPTPQc2)

7 10-bit HEVC 1:1/4 for UHD

1:1 for FHD

Ultra HD Blu-ray
8.1 10-bit HEVC No enhancement layer HDR10
8.2 SDR
8.4 HLG
9 8-bit AVC No enhancement layer SDR
Profiles not supported for new applications[20][21]
Profile Codec BL:EL resolution Backward compatibility
0 AVC 1:1/4 SDR
1 AVC 1:1 None
2 8-bit HEVC 1:1/4 SDR
3 8-bit HEVC 1:1 None
6 10-bit HEVC 1:1/4 HDR10
8.3 10-bit HEVC No enhancement layer
8.5

Dual layer

Some Dolby Vision profiles are dual layer (for example: the profile 7 used for Ultra HD Blu-ray).[21] The base layer (BL) and the enhancement layer (EL) are combined to produce a 12-bit video signal.[4]

The enhancement layer can be full enhancement layer (FEL) or minimum enhancement layer (MEL).[21]

File formats

License

Dolby Vision is a proprietary solution by Dolby.[28]

In 2021, compatible color grading systems can create Dolby Vision automatic metadata with no additional cost for content creators.[28] A $2,500 annual license is required to activate the trims allowing content creators to manually adjust the video.[28] OEM and manufacturer of a grading, mastering, editorial, or other professional application or device need to apply for a license.[28]

Dolby SVP of Business Giles Baker has stated that the royalty cost for Dolby Vision is less than $3 per TV.[29][30][31]

Adoption

Hardware

Content distribution

Software

  • Color grading:[28]
  • Encoder:
    • x265: Profile 5, profile 8.1 and profile 8.2 (since version 3.0)[41]
  • Media player:
    • Exoplayer (open source, for Android)[42]
    • Shaka Player (open source, device dependent)[42]
    • Libplacebo (as part of VideoLAN project) implemented support for Dolby Vision profile 5's IPTPQc2 color space, MMR and reshaping, yet no support of dynamic metadata and NLQ yet.[43]
    • The first open source player to support profile 5 was mpv.[citation needed]

References

  1. ^ a b c Dolby. "Dolby Vision Whitepaper - An introduction to Dolby Vision" (PDF). Archived (PDF) from the original on 2020-09-29. Retrieved 24 April 2021.
  2. ^ a b "Understanding HDR10 and Dolby Vision". GSMArena.com. Retrieved 2021-04-24.
  3. ^ "The state of HDR video mid-2017". FlatpanelsHD. Retrieved 2021-04-24.
  4. ^ a b Dolby Laboratories. "Dolby Vision Whitepaper" (PDF). Archived (PDF) from the original on 20 May 2020. Retrieved 24 August 2016.
  5. ^ "Dolby Vision for Content Creators". professional.dolby.com. Retrieved 2021-04-24.
  6. ^ a b c "Create in Dolby Vision, now on the full iPhone 12 lineup". professional.dolby.com. Retrieved 2021-04-24.
  7. ^ "CES 2014: Dolby Vision promises a brighter future for TV, Netflix and Xbox Video on board". Expert Reviews. Retrieved 2021-04-24.
  8. ^ davidsusilouncensored (2014-01-12). "The Visionary Dolby Vision at #CES2014". David Susilo Uncensored. Retrieved 2021-04-24.
  9. ^ "HDR terminology demystified". FlatpanelsHD. 2019-08-23. Archived from the original on 2020-04-06. Retrieved 2021-10-09.
  10. ^ Roberts, Becky; February 2021, Tom Parsons 21. "Dolby Vision IQ: everything you need to know". whathifi. Retrieved 2021-04-24.{{cite web}}: CS1 maint: numeric names: authors list (link)
  11. ^ "Dolby Vision cinema targets & trims FAQs". Retrieved 2022-01-26.
  12. ^ "Dolby Vision for Content Creators" (PDF). Archived (PDF) from the original on 1 January 2019. Retrieved 23 May 2019.
  13. ^ Dolby Laboratories. "Dolby Vision Whitepaper" (PDF). Archived (PDF) from the original on 4 June 2016. Retrieved 24 August 2016.
  14. ^ "SMPTE ST 2094 and Dynamic Metadata" (PDF). Society of Motion Picture and Television Engineers. Archived (PDF) from the original on 2 February 2017. Retrieved 25 January 2017.
  15. ^ Michael Bizzaco; Ryan Waniata; Simon Cohen (19 December 2020). "HDR TV: What it is and why your next TV should have it". Digital Trends. Designtechnica Corporation. Archived from the original on 21 December 2020. Retrieved 2 January 2021.
  16. ^ a b Dolby (23 Jan 2021). "Dolby Vision Metadata Levels". Archived from the original on 2021-02-25. Retrieved 24 April 2021.
  17. ^ a b Pocket-lint (2020-10-13). "What is Dolby Vision? Dolby's own HDR tech explained". www.pocket-lint.com. Retrieved 2021-04-24.
  18. ^ "Dolby Vision for Content Creators - Workflows". professional.dolby.com. Archived from the original on 2021-04-24. Retrieved 2021-04-24.
  19. ^ "Dolby Vision and Independent Filmmaking". Mystery Box. Retrieved 2021-04-24.
  20. ^ a b Dolby. "Dolby Vision Profiles and Levels Version 1.3.2 - Specification" (PDF). Archived from the original (PDF) on 29 September 2020. Retrieved 12 February 2021.
  21. ^ a b c d Dolby (2 November 2020). "What are Dolby Vision profiles?". Archived from the original on 2021-03-02. Retrieved 2021-10-09.
  22. ^ Dolby Laboratories (12 December 2017). "Dolby Vision Streams Within the ISO Base Media File Format v2.0" (PDF). Archived (PDF) from the original on 29 September 2020. Retrieved 25 April 2021.
  23. ^ a b c d Dolby (16 Nov 2020). "How to signal Dolby Vision in ISOBMFF format (AKA mp4 container)?". Archived from the original on 2021-03-02. Retrieved 27 April 2021.
  24. ^ Dolby Laboratories (13 November 2018). "Dolby Vision Streams within the HTTP Live Streaming format v2.0" (PDF). Archived (PDF) from the original on 29 September 2020. Retrieved 25 April 2021.
  25. ^ Dolby Laboratories. "Dolby Vision Streams Within the MPEG-2 Transport Stream Format v1.2" (PDF). Archived (PDF) from the original on 29 September 2020. Retrieved 25 April 2021.
  26. ^ Dolby Laboratories (13 November 2018). "Dolby Vision Streams within the MPEG-DASH format v2.0" (PDF). Archived (PDF) from the original on 29 September 2020. Retrieved 25 April 2021.
  27. ^ "Add AVC and HEVC codec mappings with BlockAdditionMapping 2 by JeromeMartinez · Pull Request #390 · ietf-wg-cellar/matroska-specification". GitHub. Retrieved 2021-04-25.
  28. ^ a b c d e "Dolby Vision for Content Creators - Solutions". professional.dolby.com. Archived from the original on 2020-12-05. Retrieved 2021-04-24.
  29. ^ Tim Moynihan (20 January 2016). "What you need to know before buying an HDR TV". Wired. Archived from the original on 2 February 2017. Retrieved 26 January 2017.
  30. ^ Giles Baker (20 September 2016). "Dolby Vision and HDR10: What Format War?". LinkedIn. Archived from the original on 11 November 2020. Retrieved 26 January 2017.
  31. ^ Lee Neikirk (9 September 2016). "Dolby Says The "HDR Format War" Doesn't Exist". Reviewed.com. Archived from the original on 23 January 2021. Retrieved 26 January 2017.
  32. ^ "TV Database". FlatpanelsHD. Retrieved 2021-04-24.
  33. ^ Cruz, Claudia. "LG G6 is the first phone to debut Dolby Vision HDR". CNET. Retrieved 2021-04-24.
  34. ^ Wong, Raymond. "The iPhone 8 and 8 Plus don't really support true HDR video playback". Mashable. Archived from the original on 2019-10-26. Retrieved 2019-10-26.
  35. ^ "Xiaomi Mi 11 Ultra review". GSMArena.com. Retrieved 2021-04-29.
  36. ^ "Xiaomi Mi 11 Pro debuts with Snapdragon 888 and Samsung's GN2 50MP sensor". GSMArena.com. Retrieved 2021-04-29.
  37. ^ "Xbox Support". support.xbox.com. Retrieved 2021-10-09.
  38. ^ Sarkar, Samit (2021-09-28). "Dolby Vision gaming goes live on Xbox Series X". Polygon. Retrieved 2021-10-09.
  39. ^ "Ultra HD Blu-ray: Everything you need to know". www.digitaltrends.com. 26 September 2019. Archived from the original on 2015-05-25. Retrieved 2021-04-24.
  40. ^ "Cinema-grade video for all: Vimeo supports Dolby Vision for Apple devices | Vimeo". Vimeo Blog. 2021-09-10. Retrieved 2021-10-09.
  41. ^ "Release Notes — x265 documentation". x265.readthedocs.io. Retrieved 2021-04-24.
  42. ^ a b Dolby (16 Nov 2020). "Which open source players support Dolby Vision?". Archived from the original on 2021-03-02. Retrieved 27 April 2021.
  43. ^ "colorspace: add support for Dolby Vision (!207) · Merge requests · VideoLAN / libplacebo". GitLab. Retrieved 2021-12-16.
  1. ^ iPhone 8/8 Plus, XR, 11, and SE (2nd generation) can play Dolby Vision content despite not having an HDR-ready display, done by down-converting the HDR content to fit the display while still having some enhancements to dynamic range, contrast, and wide color gamut compared to standard content.[34]
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