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BBC Red Button HD
BBC Red Button is a brand used for digital interactive television services provided by the BBC, and broadcast in the United Kingdom. The services replaced Ceefax, the BBC's analogue teletext service. BBC Red Button's text services were due to close on 30 January 2020, but the switch off was suspended on 29 January 2020 following protests. History and branding The service was launched on 23 September 1999 as BBC Text. It was relaunched in November 2001 under the BBCi brand and operated under this name until late 2008, when it was rebranded as BBC Red Button. The "red button" name refers to the common interface on remote controls for digital televisions and set-top boxes, a red push-button that launches digital teletext services. Although initially marketed as a spectacular new form of television, by 2008 this had given way to positioning iTV as ‘everyday’. This was due in part to the institutional landscape of television in the UK. In September 2009, the BBC celebrated 10 ye ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
576i
576i is a standard-definition digital video mode, originally used for digitizing analog television in most countries of the world where the utility frequency for electric power distribution is 50 Hz. Because of its close association with the legacy color encoding systems, it is often referred to as PAL, PAL/ SECAM or SECAM when compared to its 60 Hz (typically, see PAL-M) NTSC-colour-encoded counterpart, 480i. The ''576'' identifies a vertical resolution of 576 lines, and the ''i'' identifies it as an interlaced resolution. The field rate, which is 50 Hz, is sometimes included when identifying the video mode, i.e. 576i50; another notation, endorsed by both the International Telecommunication Union in BT.601 and SMPTE in SMPTE 259M, includes the frame rate, as in 576i/25. Operation In analogue television, the full raster uses 625 lines, with 49 lines having no image content to allow time for cathode ray tube circuits to retrace for the next frame (see Ver ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
