Bürgerfernsehen Gera (background-colour on all pages, test pages 460 to 485) and SWR Fernsehen (included completely backwards-compatible Level 2.5 teletext, with higher quality text and graphics on nearly all pages). By late 2021, SWR Fernsehen stopped using the system, but ZDF, 3sat, Bayerisches Fernsehen and Phoenix has at least some Level 2.5 enhanced pages. One of the problems with Level 2.5 is that it often takes several transmission cycles before the higher resolution items show on the screen. In order to watch Level 2.5 teletext, a rather recent television set with a special decoder chip is required. If not, Level 1.5 text will be shown. Level 3 New features: Dynamically Redefined Character Set (DRCS) allowing the display of non-Roman characters (e.g. Arabic and Chinese) Pictorial graphic characters can also be defined (Level 3 was replaced by level 3.5) Level 3.5 (1997) Extends the number of re-definable characters and their complexity and introduces different font styles and proportional spacing. New features: Dynamically Redefined Character Set (DRCS) allowing the display of non-Roman characters (e.g. Arabic and Chinese) Pictorial graphic characters can also be defined Different font styles Proportional spacing. Level 4 (1981) Level 4 was proposed in 1981 and tested by IBA. No TV set implements this level. Vector graphics in resolutions of 320×256 Needs computing power to generate the display from a sequence of drawing instructions 250,000 colours palette Level 5 Level 5 allows full-definition still pictures with better quality than video cameras. No TV set implements this level. Modulated onto a carrier No noise added to the picture during transmission Image compression used See also Antiope - French teletext standard (CCIR Teletext System A) NABTS – North American Teletext Specification (CCIR Teletext System C) JTES - Japanese Teletext Specification (CCIR Teletext System D) NAPLPS – North American Presentation Level Protocol Syntax Mullard SAA5050 a popular teletext decoder chip List of teletext services Teletext character set Text semigraphics Further reading World System Teletext Technical Specification, UK Department of Trade and Industry, 1985. Also retitled as World System Teletext and Data Broadcasting System Technical Specification, various revisions until 1989. CCIR 653 (now ITU-R BT.653) set of four standards for teletext systems worldwide. Adopted 1986. Revisions 2 and 3 were published in 1993 and 1998. WST was formalised by this standard as CCIR Teletext System B. Enhanced Teletext specification ETS 300 706 (ETSI, 1997); Version 1.2.1, April 2003. Current European standard for CCIR