As digital video evolved, resolution and frame rates increased, but image quality remained limited for a long time. Standard video (SDR, Standard Dynamic Range) is designed for a narrow brightness range, with a limited ratio between the darkest and brightest areas of a frame. It typically uses 8-bit color and the Rec. 709 color space, which means that details in dark areas may be lost or bright areas may become overexposed. Even powerful processors and image-processing algorithms could only improve the picture to a limited extent.
To address this problem, HDR (High Dynamic Range) was developed. It expands the dynamic range, allowing video to reproduce a much wider range of brightness levels and improving image quality. HDR is not just a feature of the TV itself. The video must also be recorded using a specific method and include metadata, which is additional information about the image being displayed.
How an HDR Image Is Created
The main goal of HDR is to preserve details in both the darkest and brightest areas of a frame. There are two main approaches.
- Exposure bracketing. Several frames are captured at different exposure levels. One is made brighter to capture details in the shadows, while another is made darker to preserve highlights. The frames are then combined, using the areas with the most suitable exposure from each one. This can be done with several cameras simultaneously or with a single camera capturing frames sequentially. The latter approach is not well suited to dynamic scenes because objects may move between exposures, creating ghosting and other artifacts.
- A sensor with a wide dynamic range. Modern cameras can capture a broad range of brightness levels in a single frame without combining multiple exposures. In other words, the camera captures several images, which its processor analyzes to produce a single final frame.
The result is an image with well-preserved details and smooth color transitions.
How HDR Is Transmitted and Displayed
Capturing HDR video is not enough. It must also be encoded and transmitted so that the screen can display it correctly. Metadata is transmitted alongside the video stream. It contains technical information about brightness, contrast, and color that tells the TV how to display the image. Therefore, the TV must support the relevant standard. Otherwise, the image will be displayed in the standard SDR format.
There are two methods of transmitting this information.
- Static metadata is defined once for the entire video.
- Dynamic metadata changes from scene to scene or even from frame to frame.
Overview of HDR Standards
HDR10
The basic open HDR format, standardized by the Consumer Technology Association (CTA) in 2015. It is mandatory for 4K Blu-ray discs and serves as the foundation for HDR10+ and many Dolby Vision profiles. It uses 10-bit color and the Rec. 2020 color space, although actual displays usually cover only part of this color gamut.
Static metadata is defined once for the entire movie and describes the mastering monitor, the maximum frame brightness, and the average brightness. The TV itself determines how to map the brightness levels to its display capabilities, so the picture can look noticeably different on different TV models, and some details may be lost in dark scenes. The format is free to use and is supported by virtually all HDR equipment.
HDR10+
An evolution of HDR10 announced by Samsung and Amazon in 2017. The format was later standardized by the HDR10+ consortium, founded by Samsung, Panasonic, and 20th Century Fox. HDR10+ adds dynamic metadata based on the SMPTE ST 2094-40 standard to the basic HDR10 stream. This metadata is transmitted frame by frame, allowing the TV to adjust brightness and contrast more precisely for each moment of the video according to the capabilities of its display panel.
Devices that do not support HDR10+ display this content as standard HDR10. Color depth remains 10 bits. The standard is royalty-free but is not supported by all equipment.
HDR10+ Adaptive
An additional HDR10+ feature that takes room lighting into account. The TV measures ambient light using a built-in sensor and adjusts the brightness of the HDR image, making it brighter in a well-lit room and less bright in a dark room. Samsung introduced the feature in its 2021 TVs, and it was announced at the same time that HDR10 content on Prime Video would be displayed in HDR10+ Adaptive mode on compatible Samsung TVs. The HDR10+ website describes this feature as part of the HDR10+ Advanced specification introduced in 2025.
HDR10+ Gaming
A gaming version of HDR10+ developed by HDR10+ Technologies. According to Samsung, before this format was introduced, games and displays could not identify each other’s capabilities, so HDR settings were either generalized or had to be selected manually. With HDR10+ Gaming, the game engine and the display device exchange information directly, allowing the game to identify the display’s capabilities and generate an HDR image optimized for that screen. Automatic adjustment without manual calibration is one of the advertised features. When the format was introduced, it was available on PCs with supported NVIDIA graphics cards and on newer Samsung TVs and monitors.
HDR10+ Advanced
A newer standard designed for flagship TVs with very high peak brightness, powerful processors, and large screens. Prime Video is launching it on Samsung’s 2026 TVs starting in August 2026. Its announced features include the following.
- Enhanced Overall Brightness: Metadata helps make better use of the high brightness capabilities of premium TVs.
- Intelligent Motion Smoothing: The system automatically determines whether motion smoothing is needed.
- AI-powered genre detection to select image-processing settings, along with a wider range of colors based on metadata supplied by content creators.
Dolby Vision
A licensed standard developed by Dolby and introduced in 2014. It uses dynamic metadata that can change from scene to scene or from frame to frame. For streaming, the image is generally 10-bit, while 12-bit video is possible only in certain profiles, such as those used on 4K Blu-ray discs. Dolby Vision has several profiles, some designed for streaming, others for discs, and some compatible with HDR10 on TVs that do not support Dolby Vision.
In 2025, Dolby announced Dolby Vision 2. According to the company, it adds AI-based picture optimization for viewing conditions and frame-by-frame control of motion smoothing. Older TVs can still play this content, but the new features require Dolby Vision 2 support. The standard requires a paid license for manufacturers. Samsung does not support Dolby Vision in its TVs and instead focuses on HDR10+.
HLG (Hybrid Log-Gamma)
A format developed by the BBC and NHK for television broadcasting and live transmissions. It is included in the ITU-R BT.2100 recommendation. HLG does not use metadata because brightness information is encoded directly into its transfer function, whose lower portion is similar to the conventional SDR gamma curve, while the upper portion is logarithmic and handles bright areas.
This allows the same signal to be displayed on both HDR and SDR TVs. On an HDR screen, the image benefits from an expanded dynamic range, while on an SDR screen, it appears normal, although colors may look slightly muted on older models without support for a wide color gamut. The format is royalty-free and typically uses 10-bit color. It cannot adjust each scene as precisely as formats with dynamic metadata, but it is simpler to use for broadcasting and does not require separate SDR and HDR streams.
Comparison of HDR Standards
| Standard | Metadata | Color Depth | License | Year |
|---|---|---|---|---|
| HDR10 | Static | 10-bit | Open | 2015 |
| HDR10+ | Dynamic (frame-by-frame) | 10-bit | Royalty-free | 2017 |
| HDR10+ Adaptive | Dynamic (HDR10+) with ambient light sensor adjustments | 10-bit | Not specified | 2021 |
| HDR10+ Gaming | More extensive than HDR10, according to Samsung | 10-bit | Not specified | 2022 |
| HDR10+ Advanced | Extended scene metadata, according to Samsung | 10-bit | Royalty-free | 2025 |
| Dolby Vision | Dynamic | 10–12-bit | Paid license | 2014 |
| HLG | Not used | 10-bit | Open | 2015 |
