480i

480i is a shorthand name for the video mode used for standard-definition analog or digital television in most of the Americas (with the exception of Argentina, Paraguay and Uruguay), Caribbean, Myanmar, Japan, South Korea, Taiwan and Philippines. The 480 identifies a vertical resolution of 480 lines, and the i identifies it as an interlaced resolution. The field rate, which is 60 Hz (or 59.94 Hz when used with NTSC colour), is sometimes included when identifying the video mode, i.e. 480i60; another notation, endorsed by both the International Telecommunication Union in BT.601 and SMPTE in SMPTE 259M, includes the frame rate, as in 480i/30. The other common standard, used in the rest of the world, is 576i.

In analogue contexts, this resolution is often called "525 lines". It is mandated by CCIR Systems M and J, which are usually paired with NTSC colour - which led to the "NTSC" name being often inaccurately used to refer to this video mode. Other colour encodings have also been used with System M, notably PAL-M in Brazil.

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