ultrahighdefinition

Ultrahighdefinition is a term used to describe video and display standards that exceed traditional high-definition resolution. It is commonly applied to Ultra High Definition (UHD), with the principal formats being 4K UHD and 8K UHD. In practice, 4K UHD refers to 3840×2160 pixels and 8K UHD to 7680×4320 pixels, both typically presented in a 16:9 aspect ratio. The term emphasizes a higher pixel count and potential for greater detail, especially on larger screens.

Standards and technology for ultrahighdefinition are defined in part by the ITU-R and related bodies. UHDTV encompasses two main resolutions: UHD-1 (4K) and UHD-2 (8K). Color representation and high-dynamic-range capabilities are governed by wider standards such as BT.2020 for color gamut and BT.2100 for HDR, with common HDR formats including HDR10, Dolby Vision, and Hybrid Log-Gamma (HLG). Video encoding for UHD content frequently uses HEVC (H.265) or AV1, and modern interfaces such as HDMI 2.0/2.1 are designed to carry the higher bandwidth required by 4K and 8K.

Applications and adoption vary by use case. Consumer electronics such as televisions, computer monitors, and streaming devices support UHD playback, while broadcasting and disc formats (e.g., Ultra HD Blu-ray) provide initial sources for 4K content. True 8K content remains relatively rare due to bandwidth, production, and equipment costs, and much 8K material is upscaled from lower resolutions. The practical benefits of ultrahighdefinition depend on display quality, source material, and viewing distance.