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Analog TV standard by nation; countries using 525-line are in green.

525-line (or EIA 525/60) is an American standard-definition television resolution used since July 1, 1941,[1][2][3] mainly in the context of analog TV broadcast systems. It consists of a 525-line raster, with 480 lines carrying the visible image at 30 interlaced frames per second. It was eventually adopted by countries using 60 Hz utility frequency as TV broadcasts resumed after World War II. With the introduction of color television in the 1950s,[4] it became associated with the NTSC analog color standard.

The system was given their letter designation as CCIR System M in the ITU identification scheme adopted in Stockholm in 1961.

A similar 625-line system was adopted by countries using 50 Hz utility frequency. Other systems, like 375-line, 405-line, 441-line and 819-line existed, but became outdated or had limited adoption.

The modern standard-definition digital video resolution 480i is equivalent to 525-line and can be used to digitize a TV signal, or to it playback generating a 525-line compatible analog signal.[5]

Analog broadcast television standards

The following International Telecommunication Union standards use 525-lines:

Analog color television systems

The following analog television color systems were used in conjunction with the previous standards (identified by a letter after the color system indication):

Digital video

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525-lines is sometimes mentioned when digitizing analog video, or when outputting digital video in an standard definition analog compatible format.

See also


  1. ^ a b Pursell, Carroll (April 30, 2008). A Companion to American Technology. John Wiley & Sons. ISBN 9780470695333 – via Google Books.
  2. ^ a b Herbert, Stephen (June 21, 2004). A History of Early Television. Taylor & Francis. ISBN 9780415326681 – via Google Books.
  3. ^ a b Meadow, Charles T. (February 11, 2002). Making Connections: Communication through the Ages. Scarecrow Press. ISBN 9781461706915 – via Google Books.
  4. ^ National Television System Committee (1951–1953), Report and Reports of Panel No. 11, 11-A, 12–19, with Some supplementary references cited in the Reports, and the Petition for adoption of transmission standards for color television before the Federal Communications Commission, n.p., 1953], 17 v. illus., diagrs., tables. 28 cm. LC Control No.:54021386 Library of Congress Online Catalog
  5. ^ "What means 480i?".
  6. ^ Parekh, Ranjan (July 1, 2013). Principles of Multimedia. Tata McGraw-Hill Education. ISBN 9781259006500 – via Google Books.
  7. ^ Poynton, Charles (January 3, 2003). Digital Video and HD: Algorithms and Interfaces. Elsevier. ISBN 9780080504308 – via Google Books.
  8. ^ a b c "Television - Color, Broadcast, CRT | Britannica". Retrieved 2023-07-26.