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Dolby Vision

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Dolby Vision
Inception2014
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 define the aspect ratio and adjust the picture based on a display's capabilities on a per-shot or even per-frame basis, optimizing the presentation.

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

Dolby Vision IQ is an update designed to optimize Dolby Vision content according to the ambient light.[9]

Dolby Cinema also uses Dolby Vision in conjunction with Dolby Atmos sound systems, though because of the use of 2.6 gamma and thus 48 nits in SDR cinemas, the 108 nits used in Dolby Cinema is already HDR.[10]

Description

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Dolby Vision allows for a maximum resolution of 8K, up to 12-bit color depth, and maximum peak brightness of 10,000 nits.[11] 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.[12]

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.[13]

This dynamic metadata allows adjusting of the image on a scene-by-scene or even frame-by-frame basis.[14] These adjustments, called "trims" in Dolby's support documents, include parameters such as Lift, Gamma, Gain, Saturation, Chroma Weight, and so on. Each set of trims is specific to its respective target displays defined by nits and colorspace. Image aspect ratios can also be defined on a per-shot basis.[15]

Technical details

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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.[16] 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 displays require:[17]

  • 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

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Dolby Vision metadata include:[15]

  • 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.[18]

Profiles

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Dolby Vision profiles[19][20]
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 10-bit HEVC No enhancement layer HDR10 or SDR or HLG
9 8-bit AVC High or High Progressive Profile SDR
10 10-bit AV1 None or HDR10 or SDR or HLG
20 10bit MV-HEVC for 3D or HEVC for 2D None (It uses proprietary IPTPQc2)
Profiles not supported for new applications[19][20]
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 10-bit HEVC No enhancement layer

Dual layer

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Some Dolby Vision profiles are dual layer (for example: the profile 7 used for Ultra HD Blu-ray).[20] The base layer (BL) and the enhancement layer (EL) are combined to produce a 12-bit video stream.[4]

The enhancement layer can be full enhancement layer (FEL) or minimum enhancement layer (MEL).[20]

File formats

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License

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Dolby Vision is a proprietary solution by Dolby.[27]

In 2021, compatible color grading systems can create Dolby Vision automatic metadata with no additional cost for content creators.[27] A $2,500 annual license is required to activate the trims allowing content creators to manually adjust the video.[27] OEM and manufacturer of a grading, mastering, editorial, or other professional application or device need to apply for a license.[27]

Dolby SVP of Business Giles Baker has stated that the royalty cost for Dolby Vision is less than $3 per TV.[28][29][30]

Despite the proprietary nature, several free software implementations of Dolby Vision exist (see § Software).

Adoption

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Hardware

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Content distribution

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Software

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  • Media players:
    • mpv, the first free software player to support Profile 5[citation needed]
    • Libplacebo (part of the VideoLAN project) has support for Dolby Vision Profile 5's IPTPQc2 color space, MMR and reshaping, but no current support for dynamic metadata or NLQ[42]
    • MPC-HC has partial support (profiles 5, 8.1, 8.4)[43][44] through MPC Video Renderer
    • Exoplayer[43]
    • Shaka Player (device dependent)
    • Windows 10/11 built-in media players (Dolby Vision Extension required, profiles 4/5/8/9 only)
  • Encoders:
    • x265: Profile 5, profile 8.1 and profile 8.2 (since version 3.0)[45]

Notes

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  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.[33]

References

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  1. ^ a b c "Dolby Vision Whitepaper - An introduction to Dolby Vision" (PDF). Dolby. Retrieved 24 April 2021.
  2. ^ "Understanding HDR10 and Dolby Vision". GSMArena.com. Retrieved 24 April 2021.
  3. ^ "The state of HDR video mid-2017". FlatpanelsHD. Retrieved 24 April 2021.
  4. ^ a b "Dolby Vision Whitepaper" (PDF). Dolby Laboratories. Archived (PDF) from the original on 20 May 2020. Retrieved 24 August 2016.
  5. ^ "Dolby Vision for Content Creators". professional.dolby.com. Retrieved 24 April 2021.
  6. ^ a b c "Create in Dolby Vision, Now on the Full iPhone 12 Lineup". Professional.Dolby.com. Retrieved 24 April 2021.
  7. ^ "CES 2014: Dolby Vision promises a brighter future for TV, Netflix and Xbox Video on board". Expert Reviews. 6 January 2014. Retrieved 24 April 2021.
  8. ^ "HDR Terminology Demystified". FlatpanelsHD. 23 August 2019. Retrieved 9 October 2021.
  9. ^ Roberts, Becky; February 2021, Tom Parsons 21 (21 February 2021). "Dolby Vision IQ: Everything You Need to Know". whathifi. Retrieved 24 April 2021.{{cite web}}: CS1 maint: numeric names: authors list (link)
  10. ^ "Dolby Vision cinema targets & trims FAQs". Retrieved 26 January 2022.
  11. ^ "Dolby Vision for Content Creators" (PDF). Archived (PDF) from the original on 1 January 2019. Retrieved 23 May 2019.
  12. ^ Dolby Laboratories. "Dolby Vision Whitepaper" (PDF). Archived (PDF) from the original on 4 June 2016. Retrieved 24 August 2016.
  13. ^ "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.
  14. ^ 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.
  15. ^ a b "Dolby Vision Metadata Levels". Dolby. 23 January 2021. Retrieved 24 April 2021.
  16. ^ "What Is Dolby Vision? Dolby's Own HDR Tech Explained". Pocket-Lint.com. 13 October 2020. Retrieved 24 April 2021.
  17. ^ "Dolby Vision for Content Creators - Workflows". professional.dolby.com. Retrieved 24 April 2021.
  18. ^ "Dolby Vision and Independent Filmmaking". Mystery Box. Retrieved 24 April 2021.
  19. ^ a b "Dolby Vision Profiles and Levels Version 1.4 - Specification". Dolby. Archived from the original on 18 December 2023. Retrieved 18 December 2023.[dead link‍]
  20. ^ a b c d "What Are Dolby Vision Profiles?". Dolby. 7 December 2023. Retrieved 18 December 2023.
  21. ^ "Dolby Vision Streams within the ISO Base Media File Format v2.0" (PDF). Dolby Laboratories. 12 December 2017. Archived (PDF) from the original on 29 September 2020. Retrieved 25 April 2021.
  22. ^ a b c d "How to Signal Dolby Vision in ISOBMFF Format (AKA mp4 Container)?". Dolby. 16 November 2020. Retrieved 27 April 2021.
  23. ^ "Dolby Vision Streams within the HTTP Live Streaming format v2.0" (PDF). Dolby Laboratories. 13 November 2018. Archived (PDF) from the original on 29 September 2020. Retrieved 25 April 2021.
  24. ^ "Dolby Vision Streams within the MPEG-2 Transport Stream Format v1.2" (PDF). Dolby Laboratories. Archived (PDF) from the original on 29 September 2020. Retrieved 25 April 2021.
  25. ^ "Dolby Vision Streams within the MPEG-DASH format v2.0" (PDF). Dolby Laboratories. 13 November 2018. Archived (PDF) from the original on 29 September 2020. Retrieved 25 April 2021.
  26. ^ "Matroska Codec Mappings". Matroska. Archived from the original on 7 August 2020. Retrieved 15 July 2024.
  27. ^ a b c d e "Dolby Vision for Content Creators - Solutions". Professional.Dolby.com. Retrieved 24 April 2021.
  28. ^ 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.
  29. ^ 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.
  30. ^ Neikirk, Lee (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.
  31. ^ "TV Database". FlatpanelsHD. Retrieved 24 April 2021.
  32. ^ Cruz, Claudia. "LG G6 Is the First Phone to Debut Dolby Vision HDR". CNET. Retrieved 24 April 2021.
  33. ^ Wong, Raymond (22 September 2017). "The iPhone 8 and 8 Plus Don't Really Support True HDR Video Playback". Mashable. Archived from the original on 26 October 2019. Retrieved 26 October 2019.
  34. ^ "Xiaomi Mi 11 Ultra review". GSMArena.com. Retrieved 29 April 2021.
  35. ^ "Xiaomi Mi 11 Pro debuts with Snapdragon 888 and Samsung's GN2 50MP sensor". GSMArena.com. Retrieved 29 April 2021.
  36. ^ "Xbox Support". support.xbox.com. Retrieved 9 October 2021.
  37. ^ Sarkar, Samit (28 September 2021). "Dolby Vision Gaming Goes Live on Xbox Series X". Polygon. Retrieved 9 October 2021.
  38. ^ "Ultra HD Blu-ray: Everything You Need to Know". DigitalTrends.com. 26 September 2019. Retrieved 24 April 2021.
  39. ^ "Cinema-grade video for all: Vimeo supports Dolby Vision for Apple devices". Vimeo. 10 September 2021. Retrieved 9 October 2021.
  40. ^ "Where to watch content in Dolby Vision". dolby.com.
  41. ^ "【全球首家】杜比视界用户投稿功能上线啦！" [[The World's First] Dolby Vision User Contribution Function Is Online!]. Bilibili.com (in Chinese). 18 August 2021. Retrieved 5 July 2023.
  42. ^ "colorspace: add support for Dolby Vision (!207) · Merge requests · VideoLAN / libplacebo". GitLab. 29 November 2021. Retrieved 16 December 2021.
  43. ^ a b "Changelogs for K-Lite Mega Codec Pack". 3 August 2023.
  44. ^ "Release MPC Video Renderer 0.6.9.2117 · Aleksoid1978/VideoRenderer". 7 August 2023 – via GitHub.
  45. ^ "Release Notes — x265 documentation". x265.readthedocs.io. Retrieved 24 April 2021.
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