High-dynamic-range television (HDR-TV) is a technology that uses high dynamic range (HDR) to improve the quality of display signals. It is contrasted with the retroactively named standard dynamic range (SDR). HDR changes how luminance and colors in videos and images are represented in the signal, allowing brighter, more detailed highlights, darker, more detailed shadows, and more intense colors. HDR allows compatible displays to receive a higher-quality image source. It does not improve a display's intrinsic properties (brightness, contrast, and color capabilities). Not all HDR displays have the same capabilities, and HDR content will look different depending on the display used; the standards specify the required conversion depending on display capabilities. HDR-TV is a part of HDR imaging, an end-to-end process of increasing the dynamic range of images and videos from their capture and creation to their storage, distribution and display. Often, HDR is used with wide color gamut (WCG) technology. WCG increases the gamut and number of distinct colors available. HDR increases the range of luminance available for each color. HDR and WCG are separable but complementary technologies. Standards-compliant HDR displays also have WCG capabilities, as mandated by Rec. 2100 and other common HDR specifications. There are a number of different HDR formats, including HDR10, HDR10+, Dolby Vision, and HLG. HDR10 is the most common format and is supported by all HDR TVs. Dolby Vision is a more advanced format that offers some additional features, such as scene-by-scene mastering. HDR10+ is a newer format that is similar to Dolby Vision but is royalty-free. HLG is a broadcast HDR format that is used by some TV broadcasters. The use of HDR in television sets began in the late 2010s. By the mid-2020s, HDR had become a standard feature in new televisions, with approximately 64% of smart TVs sold globally in 2024 supporting HDR formats.
Description Before HDR, improvements in display fidelity were typically achieved by increasing the pixel quantity (resolution), pixel density, and the display's frame rate. By contrast, HDR improves the perceived fidelity of the existing individual pixels. Standard dynamic range (SDR) is still based on and limited by the characteristics of older cathode-ray tubes (CRTs), despite the huge advances in screen and display technologies since CRT's obsolescence. SDR formats are able to represent a maximum luminance level of around 100 nits. For HDR, this number increases to around 1,000–10,000 nits. HDR can represent darker black levels and more saturated colors. The most common SDR formats are limited to the Rec. 709/sRGB gamut, while common HDR formats use Rec. 2100, which is a wide color gamut (WCG). In practice, HDR is not always used at its limits. HDR contents are often limited to a peak brightness of 1,000 or 4,000 nits and P3-D65 colors, even if they are stored in formats capable of more. Content creators can choose to what extent they make use of HDR capabilities. They can constrain themselves to the limits of SDR even if the content is delivered in an HDR format. The benefits of HDR depend on the display capabilities, which vary. No current display is able to reproduce the maximal range of brightness and colors that can be represented in HDR formats.
Benefits The highlights—the brightest parts of an image—can be brighter, more colorful, and more detailed. The larger capacity for brightness can be used to increase the brightness of small areas without increasing the overall image's brightness, resulting in, for example, bright reflections from shiny objects, bright stars in a dark night scene, and bright and colorful light-emissive objects (e.g. fire, and sunset). The shadows or lowlights—the darkest parts of an image—can be darker and more detailed. The colorful parts of the image can be even more colorful if a WCG is used. The color dynamism and wider range of colors frequently attributed to HDR video are actually a consequence of a WCG. This has become a point of significant confusion among consumers, whereby HDR and WCG are either confused for each other or treated as interchangeable. While HDR displays typically have WCGs and displays with WCGs are usually capable of HDR, one does not imply the other; there are SDR displays with WCGs. Some HDR standards specify WCG as a prerequisite of compliance. Regardless, when a WCG is available on an HDR display, the image as a whole can be more colorful due to the wider range of colors. More subjective, practical benefits of HDR video include more realistic luminance variation between scenes (such as sunlit, indoor, and night scenes), better surface material identification, and better in-depth perception, even with 2D imagery.
Preservation of content creator intent When a display’s capabilities are insufficient to reproduce all the brightness, contrast and colors that are represented in the HDR content, the image needs to be adjusted to fit the display’s capabilities. Some HDR formats (such as Dolby Vision and HDR10+) allow the content creator to choose how the adjustment will be done. Other HDR formats, such as HDR10 and hybrid log–gamma (HLG), do not offer this possibility, so the content creator's intents are not ensured to be preserved on less capable displays. For optimal quality, standards require video to be created and viewed in a relatively dark environment. Dolby Vision IQ and HDR10+ Adaptive adjust the content according to the ambient light.
Formats Since 2014, multiple HDR formats have emerged including HDR10, HDR10+, Dolby Vision, and HLG. Some formats are royalty-free and others require a license. The formats vary in their capabilities. Dolby Vision and HDR10+ include dynamic metadata while HDR10 and HLG do not. The dynamic metadata are used to improve image quality on limited displays that are not capable of reproducing an HDR video to its fullest intended extent. Dynamic metadata allows content creators to control and choose the way the image is adjusted.
HDR10
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