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High-definition television (HDTV) is a digital television broadcasting system with greater resolution than traditional television systems (NTSC, SECAM, PAL). HDTV is digitally broadcast because digital television (DTV) requires less bandwidth if sufficient video compression is used.





Contents

1 History of high-definition television
2 HDTV sources
3 Notation

3.1 Standard Display Resolutions
3.2 High-Definition Display Resolutions
3.3 Standard frame or field rates
4 Broadcast station format considerations

4.1 Types of media
4.2 List of stations
5 Technical details

5.1 Advantages of HDTV expressed in non-technical terms
5.2 Disadvantages of HDTV expressed in non-technical terms
6 Contemporary systems
7 Recording and compression
8 Table of terrestrial HDTV transmission systems
9 TV resolution
10 See also
11 References
12 External links



History of high-definition television

Further information: Analog high-definition television system
The term high definition described the television systems of the 1930s and 1940s beginning with the British 405-line black-and-white system, introduced in 1936; however, it, and the American 525-line NTSC system established in 1941, were only high definition in comparison with previous mechanical and electronic television systems. Today, the American 525-line NTSC system and the European 625-line PAL and SECAM systems are only regarded as standard definition. The post–WWII French 819-line black-and-white system was high definition in the contemporary sense, but was discontinued in 1986, a year after the final British 405-line broadcast.
In 1958, the U.S.S.R. created Тransformator (Russian: Трансформатор, "Transformer"), the first high-resolution (definition) television system capable of producing an image composed of 1,125 lines of resolution for the purpose of television conferences among military commands; as it was a military product, it was not commercialised.[1]