4K video

4K resolution, also called 4K, refers to a horizontal resolution on the order of 4,000 pixels and vertical resolution on the order of 2,000 pixels. Several 4K resolutions exist in the fields of digital television and digital cinematography. In the movie projection industry, Digital Cinema Initiatives (DCI) is the dominant 4K standard. In television and consumer media, 4K UHD or UHD-1 is the dominant 4K standard. By 2015, 4K television market share had increased greatly as prices fell dramatically during 2014 and 2015. By 2025, more than half of U.S. households are expected to have a 4K-capable TV (2160p), which would be a much faster adoption rate than that of Full HD (1080p).

The name "4K resolution" refers to a horizontal resolution of approximately 4,000 pixels. The use of width to characterize the overall resolution marks a switch from previous television standards such as 480i and 1080p, which categorize media according to its vertical dimension. Using that same convention, 4K UHD would be named 2160p.

There are two main 4K resolution standards:

Many manufacturers may advertise their products as UHD 4K, or simply 4K, when the term 4K is traditionally reserved for the cinematic, DCI resolution. This often causes great confusion among consumers.

YouTube and the television industry have adopted UHD-1 as their 4K standard. As of 2014^[update], 4K content from major broadcasters remains limited. On April 11, 2013, Bulb TV created by Canadian serial entrepreneur Evan Kosiner became the first broadcaster to provide a 4K linear channel and VOD content to cable and satellite companies in North America. The channel is licensed by the Canadian Radio-Television and Telecommunications Commission to provide educational content. However, 4K content is becoming more widely available online including on YouTube, Netflix and Amazon. By 2013, some UHDTV models were available to general consumers in the range of US$600. As of 2015^[update], prices on smaller computer and television panels had dropped below US$400.DVB expects UHD-1 Phase 2 services to be introduced by broadcasters from 2017, with features such as High Dynamic Range (using HLG and PQ at 10 or 12 bits), Wide Color Gamut (BT. 2020/2100 colorimetry), and High Frame Rate (up to 120 Hz).

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