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= HDR10+ Technology Introduction = HDR10+ is the latest and most advanced HDR technology, building upon HDR10 to further enhance the viewing experience. HDR10+ signals not just the dynamic range (the ratio of light to dark) of video content on a scene-by-scene (or even frame-by-frame) basis, it also provides, in a small amount of metadata, the scene characteristics between bright and dark so that important detail can be kept. This enables displays to reproduce images more realistically, adhering to the creator’s intent.

Whereas static HDR, such as HDR10, utilizes static tone mapping uniformly across the duration of the content, HDR10+ employs dynamic tone mapping to optimize each scene individually increasing brightness and adding contrast to fit within a display’s capabilities.

HDR10+ is a royalty-free technology easily accessible to adopters – from movie studios and filmmakers to display and device manufacturers. HDR10+ is a technology that provides descriptive dynamic metadata and defines an ecosystem for optimized scene-by-scene dynamic tone mapping.

Workflow and Ecosystem
HDR10+ is designed to utilize an HDR10 master file and fits within existing HDR post-production and distribution workflows.

The HDR10+ ecosystem is used within current systems by

·        storing HDR10+ metadata in JSON files

·        embedding HDR10+ metadata into HDR10 content

·        distributing through any digital stream (e.g. streaming/OTT is HDR10+ SEI)

·        displaying the HDR10+ content on a capable display (e.g. HDMI interfaces is through HDR10+ VSIF)

·        also displaying on mobile devices.

Metadata Generation
For offline and VOD (e.g. UHD Blu-ray, OTT, MVPD), HDR10+ Metadata may be created during the post-production, mastering process or during transcoding/encoding for distribution back-ends by HDR10+ content generation tools in two steps,

1) Identifying scene cuts, and

2) Performing an image analysis on each scene or frame to derive statistics similar to a histogram, and optionally providing a user-controlled tone curve unique to each scene.

HDR10+ metadata is easily interchanged through a low complexity JSON-structured text file, which can be easily parsed and injected into video files.

Live Encoding
As HDR10+ is delivered in every frame (duplicated per frame across scenes in offline case) “live” use cases are thus enabled. Already HEVC encoders are available which generate metadata on live content as well as mobile phones which record video and generate HDR10+ metadata during the recording.

Live encoding is easily supported in encoders with the following workflow and real time broadcast operations are supported at the point of transmission enabling a metadata-less broadcast operation if desired.

Compatibility
HDR10+ metadata follows ITU-T T.35 and can co-exist with other HDR metadata such as HDR10 static metadata that makes HDR10+ content backward compatible with non-HDR10+ TVs as shown below.

HDR10+ Content Profile
o  EOTF: SMPTE ST 2084 (PQ)

o  Chroma Sub-sampling: 4:2:0 (for compressed video sources)

o  Resolution: Agnostic (2K/4K/8K, etc.)

o  Bit Depth: 10-bit or more (up to 16-bit)

o  Color Primaries: ITU-R BT.2020

o  Maximum linearized pixel value: 10,000 cd/m2 for each color R/G/B (content)

o  Metadata (Required): Mastering Display Color Volume Metadata

o  Metadata (Optional): MaxCLL, MaxFALL

No matter the workflow used, HDR10+ technology can support the full range of HDR standards to 10,000 cd/m2, 8K and BT.2020 color gamut. Being resolution agnostic, metadata needs to be created only once and can be applied to any target resolution.

HDR10+ is applicable for HEVC and VP9 compatibility via WebM as well as any codec that supports ITU-T T.35 metadata.

Device Tone Mapping
HDR10+ displays will process the video, frame-by-frame, with HDR10+ metadata to apply the best tone mapping for the content on the device. Tone mapping happens when the source content peak luminance is higher than the display device peak luminance. Once HDR10+ content is delivered to a display device, the decoder will parse the HDR10+ metadata and video essence and process through the video pipeline. If a display doesn’t support the HDR10+ metadata, it will be simply ignored as any other optional ITU-T T.35 metadata and the display reverts to show the strict version of HDR10.

The existing HDR technology, HDR10, leads to inconsistent reproduction of HDR content from one display device to another as only limited static metadata for content can be provided.

HDR10+ provides articulated scene based statistical data and optional guided tone mapping information to the display. This data enables a consistent reproduction of the source master content across displays of varying capability. Additionally, when a knee-point is included with HDR10+ metadata, displays maintain the content’s original look in shadow detail as no tone mapping happens below the knee-point.

Quality Factors
HDR10+ processes images dynamically, which equates to scene-by-scene or frame-by-frame picture enhancement. HDR10+ allows displays to be fully capable of portraying optimized visuals with consistent color saturation and detail - no matter the display capabilities.

This dynamic approach to image optimization results in rich and accurate colors, increased scene highlights and more visible shadow details. It means that when watching a show or film, characters’ expressions and the details of a scene appear crisp and nuanced, making the scene appear more lifelike. The following is a subset of image reproduction enhancements due to HDR10+ as contrasted to traditional HDR technology.

Shadow Details Remain
Left-side Image - HDR10+ enables displays to show optimal curves with more control points than simple gamma or s-curves and does not require multiple versions to be created. For example low light details set in mastering are often crushed with a less sophisticated tone curve (like an s-curve) that then requires creatives to make additional versions to address curve limitations.

Right-side Image - HDR10+ follows the original artistic intent, up to the capabilities of the display (knee-point), before applying a tone curve. Dark details set in mastering are not tone mapped, preserving the creative look and feel in low-light areas.

{Crushed Image}

Preserves Color Hue
Left-side Image - Changes in luminance can shift color hues causing color distortion if not properly applied in the correct proportions.

Right-side Image - HDR10+ tone mapping holds the color ratios constant when applying the luminance tone curve, preserving original color hue and only adjusting luminance.

{Hue shift Image}

Banding Artifacts are Avoided
Left-side Image - Banding is a common artifact introduced by discontinuities in a poorly constructed tone curve. Kinks or bends in a tone curve can result in visual artifacts.

Right-side Image - HDR10+ utilizes a smooth, nuanced and continuous tone curve based on scene pixel distributions and is free of banding artifacts.

{Banding Image}

Retains Details in Highlights
Left-side Image - Details in highlights are easily washed out or clipped when tone mapped. Overly aggressive tone curve eliminates specular highlight details and clips the brightest pixels.

Right-side Image - HDR10+ metadata is generated on scene statistics so the highest color values are taken into account when creating the tone curve, gradients in highlights are retained and the brightest pixels in the source content are appropriately mapped to the display limits.

{Clipping Image}

Overview of HDR10+Technologies, LLC
HDR10+ Technologies, LLC administers the license and certification program that ensures a premium HDR viewing experience for the HDR10+ ecosystem. HDR10+ Technologies, LLC provides the technical specifications, test specifications, and certified logo  Certification is provided through third-party Authorized Test Centers.

HDR industry stakeholders such as content providers, content distributors, display and distribution device manufacturers, systems on chip (SoC) manufacturers, tool makers and others can join the HDR10+ License program.

A current list of HDR10+ adopters can be found on the HDR10+ website, https://hdr10plus.org/adopters/.

For more information about becoming an adopter of HDR10+ or information about this white paper, please contact

email:  mailto:info@hdr10plus.org%7Cinfo@hdr10plus.org or submit a registration form to HDR10+ Technologies, LLC, https://hdr10plus.org/registration/.

The latest version of the HDR10+ Whitepaper at here.

Founders

 * 20th Century Fox
 * Panasonic Corporation
 * Samsung Electronics

Becoming an HDR10+ Adopter
HDR10+ specifications for the logo are defined by the HDR10+ Technologies, LLC and adoption is encouraged for all --


 * Ultra-High Definition displays,
 * Ultra HD Blu-ray disc players,
 * Systems-on-chip (SoC)
 * Set-top boxes
 * A/V Receivers
 * Streaming applications
 * Mobile Devices