View source for 819 line

{{Short description|1940s French analogue high-definition television system}}

[[File:Mire de RTF Télévision Alger.jpg|thumb|"[[Marly Horses]]" test card from RTF Alger (predecessor of [[TV1 (Algerian TV channel)|TV1 Algeria]]) from 1956, originally in 819 lines.]]

'''819-line''' was an [[Analog television|analog]] monochrome [[television|TV]] system developed and used in [[France]]<ref name="auto">{{cite news |last=Stout |first=Andy |date=2020 |title=France had a national HD TV system as far back as 1949 |url=https://www.redsharknews.com/business/item/471-france-had-a-national-hd-tv-system-in-1949 |access-date= |work=RedShark}}</ref><ref name=":0">{{cite journal |last=Worswick |first=T. |date=March 11, 1959 |title=The B.B.C. Television Standards Converter |url=https://ieeexplore.ieee.org/document/7265454 |url-status=dead |journal=Journal of the SMPTE |volume=68 |issue=3 |pages=130–135 |doi=10.5594/J14437 |archive-url=https://web.archive.org/web/20180616210457/https://ieeexplore.ieee.org/document/7265454/ |archive-date=June 16, 2018 |via=IEEE Xplore|url-access=subscription }}</ref> as television broadcast resumed after [[World War II]]. Transmissions started in 1949 and were active up to 1985, although limited to France, [[Belgium]] and [[Luxembourg]].<ref name="auto1">{{cite news |last=Birkinshaw |first=Douglas C |date=February 19, 2021 |title=New television standards: effect on British television |url=https://transdiffusion.org/2021/02/19/new-television-standards-effect-on-british-television |work=Transdiffusion}}</ref> {{Dubious|date=February 2025}} It is associated with [[CCIR System E]] and [[CCIR System F|F]].<ref name="auto1"/>

== History ==
When Europe resumed TV transmissions after World War II (i.e. in the late 1940s and early 1950s) most countries standardized on [[625 lines|625-line]] television systems. The two exceptions were the British [[405-line television system|405-line system]], which had already been introduced in 1936, and the French 819-line system. During the 1940s [[René Barthélemy]] had already reached 1,015 lines<ref name="auto"/> and even 1,042 lines.

On November 20, 1948, [[François Mitterrand]], the then Secretary of State for Information, decreed a broadcast standard of 819 lines developed by [[Henri de France]];<ref name="auto"/><ref name="auto2">{{Cite web |title=Chronologie: Télévision |url=https://www.kronobase.org/chronologie-categorie-T%C3%A9l%C3%A9vision.html |website=KronoBase la chronologie universelle}}</ref> broadcasting began at the end of 1949 in this higher definition format. It was used in France by [[TF1]], and in [[Monaco]] by [[TMC (TV channel)|Tele Monte Carlo]].<ref name=":1">{{cite news |date=October 28, 2019 |title=Une bénédiction et une visite princière inaugurent Télé Monte-Carlo |url=https://www.radiotsf.fr/une-benediction-et-une-visite-princiere-inaugurent-tele-monte-carlo/ |work=Les radios au temps de la TSF}}</ref><ref name=":2">{{cite book |last=Parrot |first=Jacques |url=https://books.google.com/books?id=7v1XDwAAQBAJ&dq=Tele+Monte+Carlo+819+lignes&pg=PT276 |title=La Guerre des ondes: De Goebbels à Kadhafi |date=January 1, 1987 |publisher=Plon (réédition numérique FeniXX) |isbn=9782259238137 |via=Google Books}}</ref>

Some 819-line TV sets were available, like the ''Grammont 504-A-31'' from 1951<ref>{{cite web |title=Postwar British/European Grammont 504-A-31 |url=http://www.earlytelevision.org/grammont.html |website=Early Television Museum}}</ref> and the ''[[Philips]] 14TX100'' multi-standard 625/819-line TV from 1952.<ref>{{cite web |title=Postwar British/European Philips 14TX100 |url=http://www.earlytelevision.org/philips_14tx100.html |website=Early Television Museum}}</ref><ref>{{cite book |url=http://www.earlytelevision.org/pdf/philips_14tx100a.pdf |title=Philips 14TX100A Service Manual |publisher=Philips}}</ref>

The system was also adopted (with limited bandwidth, affecting image resolution) in 1953 in Belgium<ref name="auto" /><ref name="auto2" /> by ''[[RTBF|RTB]]'' and in 1955 in Luxembourg by ''[[RTL9#Télé-Luxembourg|Télé-Luxembourg]]''.<ref name=":3">{{cite news |last=Michel-Droit |date=May 17, 1955 |title=Télé-Luxembourg a fait du nord-est de la France la région-témoin de la concurrence en matière de télévision |url=https://www.lemonde.fr/archives/article/1955/05/17/tele-luxembourg-a-fait-du-nord-est-de-la-france-la-region-temoin-de-la-concurrence-en-matiere-de-television_1954922_1819218.html |work=Le Monde}}</ref>

Broadcasts were discontinued in Belgium in February 1968, and in Luxembourg in September 1971. Despite some attempts to create a color [[SECAM]] version of the 819-line system,<ref name="auto" /> France gradually abandoned the system in favor of the Europe-wide standard of [[CCIR System L|625-lines]] with the final 819-line transmissions taking place in Paris from the [[Eiffel Tower]] on 19 July 1983.<ref>{{cite web |last=Rozat |first=Pascal |date=October 14, 2022 |title=Histoire de la télévision: une exception française ? |url=http://larevuedesmedias.ina.fr/histoire-de-la-television-une-exception-francaise |website=La Revue des Médias}}</ref>

[[Tele Monte Carlo]] in [[Monaco]] were the last broadcasters to transmit 819-line television, closing down their transmitter in 1985.

== Electronovision ==
The 819-line video standard also saw some use in the United States, by the [[Electronovision]] motion picture process.  It was developed by producer and entrepreneur H. William "Bill" Sargent, Jr. around 1964 to produce a handful of motion pictures, theatrical plays, and specials in the 1960s and early 1970s using videotape recording utilizing the higher resolution afforded by the 819-line video standard for production, later transferred to film via kinescope for theatrical release.

Electronovision used conventional B&W television cameras ([[RCA]] TK-60 cameras were used) and [[Ampex]] [[2" quadruplex]]-format VTRs for the process that were configured to operate in the 819-line standard, which was a better fit for later transfer via a [[kinescope]] process to 35mm film than the usual 525-line 30 frame per second video standard in use in the US at the time, due to the higher resolution and the 25 fps frame rate of 819-line video being closer to the resolution and 24 fps frame rate of motion picture film.

== Technical details ==
This was arguably the world's first [[high-definition television system]], and, by today's standards, it could be called 736i (as it had 737 lines active, but one of the lines was composed of 2 halves)<ref>Report 308-2 of the XIIth Pleniary Assembly of the CCIR – Characteristics of Monochrome Television Systems</ref> with a maximum theoretical resolution of 408×368 [[Image resolution|line pair]]s (which in digital terms can be expressed as broadly equivalent to 816×736 pixels) with a 4:3 aspect ratio. By comparison with modern digital standards, [[720p]] is 1,280×720 pixels, of which the 4:3 portion would be 960×720 pixels, while [[DVD|PAL DVDs]] have a resolution of 720×576 pixels.

The [[Test card|testcards]] used with the system had resolution gratings that went up to 900 [[Television lines|TV lines]].<ref>{{cite web |title=Test card of the RTF with the horses of Marly |url=https://www.gettyimages.ca/detail/news-photo/test-card-of-the-rtf-with-the-horses-of-marly-news-photo/494233928 |website=Getty Images |date=23 October 2015}}</ref><ref>{{cite web |date=January 5, 2012 |title=Rétrospective: la mire à la télévision (1953 – 2002) |url=https://www.vivelapub.fr/retrospective-la-mire-tv/ |website=VivelaPub}}</ref> However, the theoretical picture quality far exceeded the capabilities of the analogue equipment of its time, and each 819-line channel occupied a wide 14&nbsp;[[Hertz|MHz]] of [[Very high frequency|VHF]] bandwidth.

{| class="wikitable"
|+ General technical specifications of the [[broadcast television systems]] used with 819-lines.<ref>{{cite web |title=Vertical Blanking Interval of French and Belgian 819-Line Standards |url=http://www.pembers.freeserve.co.uk/World-TV-Standards/VBI-819.pdf |url-status=dead |archive-url=https://web.archive.org/web/20060924213417/http://www.pembers.freeserve.co.uk/World-TV-Standards/VBI-819.pdf |archive-date=24 September 2006 |access-date=12 January 2022 |website=www.pembers.freeserve.co.uk}}</ref><ref>{{cite web |last=Russell |first=Richard |date=2005 |title=Colour Test Card Generator - Introduction and specification |url=http://bbcbasic.uk/tccgen/manual/tcgen0.html#standards |website=R. T. Russell: The home of BBC BASIC}}</ref>
! <small>Field frequency</small>
! <small>Active picture</small>
! <small>Field blanking</small>
! <small>No. of broad pulses</small>
! <small>Broad pulse width</small>
! <small>Line frequency</small>
! <small>Front porch</small>
! <small>Line sync</small>
! <small>Back porch</small>
! <small>Active line time</small>
! <small>Video/syncs ratio</small>
|-
| <small>50&nbsp;Hz</small>
| <small>737 lines</small>
| <small>41 lines</small>
| <small>1 per field</small>
| <small>20.0&nbsp;μs</small>
| <small>20475&nbsp;Hz</small>
| <small>0.5&nbsp;μs</small>
| <small>2.5&nbsp;μs</small>
| <small>5.0&nbsp;μs</small>
| <small>40.8&nbsp;μs</small>
| <small>70/30</small>
|}

819-lines were broadcast using two CCIR systems, [[CCIR System E|System E]] and [[CCIR System F|System F]].

=== System E ===
{{Main|CCIR System E}}

[[CCIR System E|System E]] implementation provided very good (near [[High-definition television|HDTV]]) picture quality but with an uneconomical use of bandwidth; a 625/50 signal providing the same clarity as an 819-line image, but matted down 4:3 with the same number of lines, would still need nearly 6&nbsp;MHz for the vision carrier alone (vs typical 5 to 6&nbsp;MHz in actual use), and 5&nbsp;MHz for 525/60 (vs typical 4.2&nbsp;MHz), although a 405/50 transmission could get away with only 2.5&nbsp;MHz (typical ''3&nbsp;MHz'', as [[CCIR System A|System A]] made no allowance for the [[Kell factor]] and thus had a "narrow pixel"/"tall line" appearance). Thus even an unusually crisp "standard" definition (or slightly soft 405-line) image only needed half, or even one-quarter the vision bandwidth of the 819-line system to give a "balanced" appearance, despite their lower overall resolution still seeming perfectly clear on the more affordable small-screen receivers often used in the pre-color era. With the usual additions of sound carrier and vestigial sideband the result was a combined signal that demanded approximately two to three times the bandwidth of more moderately specified standards, even when colour was added to them (as the color subcarrier resides ''within'' the luma signal space).

{| class="wikitable"
|+'''System E specifications'''
! <small>CCIR System</small>
! <small>Lines</small>
! <small>Frame rate</small>
! <small>Channel bandwidth</small> <small>(MHz)</small>
! <small>Visual bandwidth</small> <small>(MHz)</small>
! <small>Sound carrier offset</small>
! <small>Vestigial sideband</small>
! <small>Vision mod.</small>
! <small>Sound mod.</small>
|-
| [[CCIR System E|<small>E</small>]]
| <small>819</small>
| <small>25</small>
| <small>14</small>
| <small>10</small>
| <small>±11.15 (+ on odd numbered channels; − on even numbered channels)</small>
| <small>2.00</small>
| <small>Pos.</small>
| <small>AM</small>
|}

=== System F ===
{{Main|CCIR System F}}

[[CCIR System F|System F]] was an adapted 819-line system used in Belgium and Luxembourg as an answer to the bandwidth problem, using only half the original vision bandwidth and approximately half the sound carrier offset. It allowed French 819-line programming to squeeze into the 7&nbsp;MHz VHF broadcast channels used in those neighboring countries,<ref name="auto1" /> albeit with a substantial loss of horizontal resolution (408×737 effective); although this still offered approximately twice the actual clarity of 405-line System A (twice the lines, roughly the same horizontal definition), the contrast between vertical and horizontal resolution would have made it seem perceptually softer than a 625 line signal with the same bandwidth. Use of System F was discontinued in Belgium in February 1968, and in Luxembourg in September 1971.

{| class="wikitable"
|+'''System F specifications'''
! <small>CCIR System</small>
! <small>Lines</small>
! <small>Frame rate</small>
! <small>Channel bandwidth</small> <small>(MHz)</small>
! <small>Visual bandwidth</small> <small>(MHz)</small>
! <small>Sound carrier offset</small>
! <small>Vestigial sideband</small>
! <small>Vision mod.</small>
! <small>Sound mod.</small>
|-
| <small>[[CCIR System E#System F|F]]</small>
| <small>819</small>
| <small>25</small>
| <small>7</small>
| <small>5</small>
| <small>+5.5</small>
| <small>0.75</small>
| <small>Pos.</small>
| <small>AM</small>
|}

== Countries and territories that used the 819-line system ==
This is a list of nations that used the 819-line system for television broadcasting:
* {{flag|France}} ([[TF1]])<ref name="auto" /><ref name=":0" /> 
* {{flag|Belgium}} ([[RTBF|RTB]])<ref name="auto1" /><ref name="auto" /><ref name="auto2" />
* {{flag|Luxemburg}} ([[RTL9#Télé-Luxembourg|Télé-Luxembourg]])<ref name="auto1" /><ref name=":3" />
* {{flag|Monaco}} ([[TMC (TV channel)|Tele Monte Carlo]])<ref name=":1" /><ref name=":2" />
* {{flag|French Algeria}} (prior to independence)
* {{flag|Saar Protectorate}} (before 1957)

== See also ==
* [[CCIR System E]]
* [[CCIR System F]]

== References ==
{{reflist}}

{{Video formats}}
{{Analogue TV transmitter topics}}

[[Category:Television technology]]