This development is related to introduction of widescreen TVs and broadcasts,[3] with the PALplus[4] system in the European Union (mid 1990s), the Clear-Vision[5][6] system in Japan (early 1990s), and the need to downscale HD broadcasts to SD in the US. The bandwidth of the WSS signal is low enough to be recorded on VHS (at the time a popular home video recording technology). It is standardized on Rec. ITU-R BT.1119-2.[3]
A modern digital equivalent would be the Active Format Description, a standard set of codes that can be sent in a MPEG video stream, with a similar set of aspect ratio possibilities.
For 625 line analog TV systems (like PAL or SECAM), the signal is placed in line 23.[3] It begins with a run-in code and starts code followed by 14 bits of information, divided into four groups, as shown on the tables below (based on Rec. ITU-R BT.1119-2) :[7][8][9][10][1]
Note: The transmitted aspect ratio is 4:3. Within this area a 14:9 window is protected, containing all the relevant picture content to allow a wide-screen display on a 16:9 television set.
No copyright asserted or status unknown / Copyright asserted
13
Copying not restricted / Copying restricted
525 line systemsEdit
525 line analog systems (like NTSC or PAL-M) made a provision for the use of pulses for signaling widescreen and other parameters, introduced with the development of Clear-Vision (EDTV-II), a NTSC-compatible Japanese system allowing widescreen broadcasts.[11][12] On these systems the signals are present in lines 22 and 285, as 27 data bits, as defined by IEC 61880.[3][13][14][15][1][16]
The following table shows the information present on the signal, based on Rec. ITU-R BT.1119-2 ("helper" signals are EDTV-II specific):[3]
^Pollack, Andrew (September 15, 1994). "Japanese Taking to Wide-Screen TV" – via NYTimes.com.
^ETSI EN 300 294 - Television systems; 625-line television Wide Screen Signalling (WSS)(PDF). ETSI. 2003.
^Battiato, Farinella, Puglisi (2011). IISFA Member book 2011 - Image/Video Forensics: Casi di Studio(PDF). IISFA. p. 8.{{cite book}}: CS1 maint: multiple names: authors list (link)
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In television technology Wide Screen Signaling WSS 1 is digital metadata embedded in invisible part of the analog TV signal describing qualities of the broadcast in particular the intended aspect ratio of the image This allows television broadcasters to enable both 4 3 and 16 9 television sets to optimally present pictures transmitted in either format by displaying them in full screen letterbox widescreen pillar box zoomed letterbox etc 2 3 This development is related to introduction of widescreen TVs and broadcasts 3 with the PALplus 4 system in the European Union mid 1990s the Clear Vision 5 6 system in Japan early 1990s and the need to downscale HD broadcasts to SD in the US The bandwidth of the WSS signal is low enough to be recorded on VHS at the time a popular home video recording technology It is standardized on Rec ITU R BT 1119 2 3 A modern digital equivalent would be the Active Format Description a standard set of codes that can be sent in a MPEG video stream with a similar set of aspect ratio possibilities Contents 1 625 line systems 2 525 line systems 3 See also 4 References 5 External links625 line systems EditFor 625 line analog TV systems like PAL or SECAM the signal is placed in line 23 3 It begins with a run in code and starts code followed by 14 bits of information divided into four groups as shown on the tables below based on Rec ITU R BT 1119 2 7 8 9 10 1 Group 1 Aspect ratio Bits 0 to 3 Aspect ratio Picture placement inside the broadcast area Active lines0000 0001 Full format 4 3 nbsp 5760010 Letterbox 16 9 top nbsp 4300011 0100 Letterbox 14 9 top nbsp 5040101 0110 0111 Full format 14 9 centre shoot and protect 14 9 see note nbsp 5761000 Letterbox 14 9 centre nbsp 5041001 1010 1011 Letterbox deeper than 16 9 centre nbsp undefined1100 1101 Letterbox 16 9 centre nbsp 4301110 Full format 16 9 anamorphic nbsp 5761111 Note The transmitted aspect ratio is 4 3 Within this area a 14 9 window is protected containing all the relevant picture content to allow a wide screen display on a 16 9 television set Group 2 to 4 Bit Item Group4 Camera Mode interlaced PALplus Film Mode progressive scan 2 Enhanced Services5 Conventional PAL PALplus Motion Adaptative Colour Plus encoding6 No Vertical helper PALplus Vertical helper present7 Reserved Ghost cancellation8 No subtitles subtitles within teletext 3 Subtitles9 No open subtitles Subtitles in active image area10 Subtitles out of active image area Reserved11 No surround sound Surround sound mode 4 Reserved12 No copyright asserted or status unknown Copyright asserted13 Copying not restricted Copying restricted525 line systems Edit525 line analog systems like NTSC or PAL M made a provision for the use of pulses for signaling widescreen and other parameters introduced with the development of Clear Vision EDTV II a NTSC compatible Japanese system allowing widescreen broadcasts 11 12 On these systems the signals are present in lines 22 and 285 as 27 data bits as defined by IEC 61880 3 13 14 15 1 16 The following table shows the information present on the signal based on Rec ITU R BT 1119 2 helper signals are EDTV II specific 3 Bit Item1 Reference signal2 Reference signal3 Aspect ratio 4 3 full format 16 9 letterbox 4 Even parity for B3 to B55 Reserved6 Field type First field Next field 7 Frame type Reference frame Other frame 8 Vertical temporal helper no yes 9 Vertical high resolution helper no yes 10 Horizontal helper no yes 11 Horizontal helper pre combing no yes 12 to 14 For TV station use15 to 17 Reserved18 to 23 Error correction codes for B3 to B1724 Reference signal25 to 27 Confirmation signalSee also EditPALplus Clear Vision Active Format Description AFD TeletextReferences Edit a b c APPLICATION NOTE 9716 Widescreen Signaling WSS Renesas 1988 Loncaric Matej Tralic Dijana Brzica Maja Petrovic Juraj Grgic Sonja September 17 2009 Managing mixed HD and SD broadcasting pp 79 82 via IEEE Xplore a b c d e f RECOMMENDATION ITU R BT 1119 2 WIDE SCREEN SIGNALLING FOR BROADCASTING PDF ITU 1998 RECOMMENDATION ITU R BT 1197 1 Enhanced wide screen PAL TV transmission system the PALplus system PDF itu int FUKINUKI Takahiko EDTV Pollack Andrew September 15 1994 Japanese Taking to Wide Screen TV via NYTimes com ETSI EN 300 294 Television systems 625 line television Wide Screen Signalling WSS PDF ETSI 2003 Battiato Farinella Puglisi 2011 IISFA Member book 2011 Image Video Forensics Casi di Studio PDF IISFA p 8 a href Template Cite book html title Template Cite book cite book a CS1 maint multiple names authors list link All You Ever Wanted to Know About PALplus but were Afraid to Ask Archived from the original on 3 March 2016 Fluke PM5420 Application Note PALplus PDF assets fluke com Archived from the original PDF on 3 March 2016 Retrieved 12 January 2022 Nakayama K Kojima T Miyaguchi H Sawaragi T Yaguchi Y August 5 1995 EDTV II decoder by SVP2 the 2nd generation of scan line video processor IEEE Transactions on Consumer Electronics 41 3 634 642 doi 10 1109 30 468089 via IEEE Xplore The Journal of the Institute of Television Engineers of Japan www jstage jst go jp AN9716 Widescreen Signaling WSS Renesas Electronics Corporation 1998 RECOMMENDATION ITU R BT 1298 Enhanced wide screen NTSC TV transmission system PDF ITU 1997 Kageyama Masahiro 2010 Thesis Research on high image quality and high functionality of television PDF Jack Keith Tsatsoulin Vladimir 2002 09 11 Dictionary of Video and Television Technology Gulf Professional Publishing ISBN 978 1 878707 99 4 External links EditRenesas AN9716 Widescreen Signaling WSS covering 625 lines and 525 lines standard Retrieved from https en wikipedia org w index php title Widescreen signaling amp oldid 1145670752, wikipedia, wiki, book, books, library,
