Home > Blog
Dangbei · 05 Jun 2020
With the popularity of 4K TV, an increasing number of people are demanding more 4k images.
Meanwhile, It also generates a lot of professional nouns. But the truth is, what’s the difference between 4k and UHD?
The term ”4k” originally came from the Digital Cinema Initiative(DCI), a consortium of film studies that standardized the production of 4k content and the regulation of digital projection. In this case, 4K is 4,096 x 2,160, four times the previous standard for digital editing and projection (2K or 2,048 x 1,080).4K is the horizontal pixel count (4,096) of approximately 4,000. The 4K standard is not only a resolution, but it also defines how 4K content is encoded.DCI 4K streams are compressed using JPEG2000 and can have bit rates of up to 250Mbps with a 12-bit 4:4:4 color depth.
Ultra High Definition (UHD for short) is the next step in what's called Full HD, the official name for a display resolution of 1,920 x 1,080. UHD triples the resolution to 2,160 x 3,840. it's not the same as the aforementioned 4K resolution - however, almost all of the TVs or displays you see billed as 4K are actually UHD. of course, some panels are 4,096 x 2,160 with an overall aspect ratio of 1.9:1. but the vast majority are 3,840 x 2,160 with an aspect ratio of 1.78:1.
UHD has a physical resolution of 3840 x2160 (4K x 2K), so it’s also known as 4K Ultra HD, which is four times the resolution of Full HD (1920 x 1080) televisions and eight times higher than HD (1280 x 720) displays.
The higher the resolution gets, the clearer the picture, and the detail is. the viewing distance can be reduced by half compared to ordinary HD TVs of the same size while you watching ultra-high-definition TV, and the pixel lattice of the display is not visible. It will be occupied by the TV screen, and the viewing distance is within one meter to present a clearer, more detailed, more realistic, and natural picture, bringing you an immersive audio-visual entertainment experience!
From a technical point of view, 4K is the standard for film compression with a resolution of 4096 × 2160, supporting an aspect ratio of 1.9 to 1 (the ratio of width to height), as most movies are shot in 1.9 to 1 ratio, and the cinema's 4K resolution can be perfectly docked.
UHD uses the same horizontal line (2160)as the 4K standard but uses the aspect ratio of the standard HD TV HDTV at 16:9 (or about 1.78 HDTV). As a result, the resolution of the UHD is 3840 x 2160 (256 pixels narrower than the cinema 4K).
Now, it seems that manufacturers are not aware of the difference between 4K and UHD. But probably for market reasons, they seem to insist on using 4K. In order not to conflict with the actual 4K standard of DCI, some manufacturers seem to be using the phrase "4K UHD", although some manufacturers are only using "4K".
UHD (UHD) has a physical resolution of 3800 x2160 (4K x 2K), so it is also called 4K Ultra HD, which is four times the resolution of Full HD (FHD,1920 x1080) televisions and eight times higher than HD (HD,1280 x 720) displays.