South Africa has started the process of migrating television broadcasts from the analogue Phase Alternate Line (PAL) system introduced in 1975 to a digital system that is more efficient and made possible by technical progress, mainly in computer processing since the 1960s when PAL was introduced in Europe. PAL is the analogue television standard for most of Europe and large parts of Africa and Asia, including China and India. Its main competitors were the French SECAM (also widely used in Africa) and the North American NTSC (also used in Japan, South Korea and a few other countries). This has meant that a German or Kenyan analogue television set, for example, could be used without problem in South Africa but that a Japanese or American one would certainly not work.
Digital television broadcasting (over the air or OTA) more efficiently uses the available spectrum and allows for the transmission of many more channels. This is, indeed, why satellite broadcasting (like DSTV in South Africa) has been digital for some time now. The International Telecommunication Union (ITU) has been driving a world-wide effort to convert OTA broadcasts to a digital standard. In SA this is essentially the SABC and e-TV. The migration to digital broadcasting has already been completed in the United States and in the SADC region, Mauritius is nearly done. The SADC region had decided to adopt the DVB-T (Digitial Video Broadcasting – Terrestrial) standard that is also in use in Europe, Indian and Australia. DVB-T is an open standard which incorporates some patented algorithms for encoding of the signal.
Recently, the South African government has started to suggest that SA might switch to the Japanese ISDB (Integrated Services Digital Broadcasting) standard. Since trials of DVB-T have already started, such a switch would imply considerable cost for the industry. It would also put South Africa's chances of completing the conversion from analogue to digital television by 2015 in considerable jeopardy!
Further reading
Digital TV standards: The truth behind it by Jan Vermeulen, MyBroadband (10 June, 2010)
http://mybroadband.co.za/news/broadcasting/12989-Digital-standards-The-truth-behind.html or http://www.webcitation.org/5qbKvRh6n
Digital TV conspiracy: Is govt lying? by Candice Jones, ITWeb online telecoms editor (Johannesburg, 10 Jun 2010)
Geen opmerkings nie:
Plaas 'n opmerking