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{{Short description|Colour encoding system for analogue television}}
{{For-multi|the standard-definition digital video mode sometimes referred to as PAL or PAL/SECAM|576i|other uses}}
{{Use British English|date=November 2019}}{{Use dmy dates|date=August 2019}}

[[Image:PAL-NTSC-SECAM.svg|thumb|500px|right|Analog television encoding systems by nation: [[NTSC]] ({{ font color | green | green }}), [[SECAM]] ({{ font color | #ff7700 | orange }}), and PAL ({{ font color | blue | blue }})]]

'''Phase Alternating Line''' ('''PAL''') is a colour encoding system for [[analog television]]. It was one of three major analogue colour television standards, the others being [[NTSC]] and [[SECAM]]. In most countries it was broadcast at [[625 lines]], 50 fields (25 frames) per second, and associated with CCIR analogue [[broadcast television systems]] [[CCIR System B|B]], [[CCIR System D|D]], [[CCIR System G|G]], [[CCIR System H|H]], [[CCIR System I|I]] or [[CCIR System K|K]]. The articles on analog [[broadcast television systems]] further describe [[frame rate]]s, [[image resolution]], and audio modulation.

PAL video is [[composite video]] because [[Luma (video)|luminance]] (luma, monochrome image) and [[chrominance]] (chroma, colour applied to the monochrome image) are transmitted together as one signal. A latter evolution of the standard, [[PALplus]], added support for [[widescreen]] broadcasts with no loss of vertical [[image resolution]], while retaining compatibility with existing sets. Almost all of the countries using PAL are currently in the [[Digital television transition|process of conversion]], or have already converted transmission standards to [[DVB]], [[ISDB]] or [[Digital Terrestrial Multimedia Broadcast|DTMB]]. The PAL designation continues to be used in some non-broadcast contexts, especially regarding [[Console video game|console video games]].

== Geographic reach ==
PAL was adopted by most European countries, by several African countries, by [[Argentina]], [[Brazil]], [[Paraguay]], [[Uruguay]], and by most of [[Asia–Pacific|Asia Pacific (including the Middle East and South Asia)]].<ref name="dvd-replica_com-palnations"/> Countries in those regions that did not adopt PAL were [[France]],<ref name="auto4">{{cite web |date=23 February 2009 |title=PGC categories – Countries using SECAM standard |url=http://dvd-replica.com/DVD/secamnations.php |archive-url=https://web.archive.org/web/20090223080729/http://dvd-replica.com/DVD/secamnations.php |archive-date=2009-02-23}}</ref> Francophone Africa,<ref name="auto4" /> several ex-[[Soviet Union|Soviet]] states,<ref name="auto4" /> [[Japan]],<ref name="auto3">{{cite web |date=22 April 2009 |title=PGC categories – Countries using NTSC standard |url=http://dvd-replica.com/DVD/ntscnations.php |archive-url=https://web.archive.org/web/20090422022808/http://dvd-replica.com/DVD/ntscnations.php |archive-date=2009-04-22}}</ref> [[South Korea]], [[Liberia]], [[Myanmar]], the [[Philippines]],<ref name="auto3" /> and [[Taiwan]].<ref name="auto3" />

=== PAL region ===
With the introduction of [[home video]] releases and later digital sources (e.g. [[DVD-Video]]), the name "PAL" might be used to refer to digital formats, even though they use completely different colour encoding systems. For instance, [[576i]] (576 interlaced lines) digital video with colour encoded as [[YCbCr]], intended to be backward compatible and easily displayed on legacy PAL devices, is usually mentioned as "PAL" (eg: "PAL DVD"). Likewise, video game consoles outputting a 50&nbsp;Hz signal might be labeled as "PAL", as opposed to 60&nbsp;Hz on NTSC machines. These designations should not be confused with the analog colour system itself.

== History ==
In the 1950s, the Western European countries began plans to introduce colour television, and were faced with the problem that the [[NTSC]] standard demonstrated several weaknesses, including colour tone shifting under poor transmission conditions, which became a major issue considering Europe's geographical and weather-related particularities. To overcome NTSC's shortcomings, alternative standards were devised, resulting in the development of the PAL and SECAM standards. The goal was to provide a colour TV standard for the European picture frequency of 50&nbsp;[[field (video)|fields]] per second (50&nbsp;[[hertz]]), and finding a way to eliminate the problems with NTSC.

PAL was developed by [[Walter Bruch]] at [[Telefunken]] in [[Hanover]], [[West Germany]], with important input from {{Interlanguage link|Gerhard Mahler|de|3=Gerhard Mahler (Fernsehtechniker)|lt=Gerhard Mahler}}.<ref>{{cite web |date=2 March 2020 |title=Walter Bruch and the PAL Color Television System |url=http://scihi.org/walter-bruch/ |access-date=6 July 2021 |quote=In 1963, when he gave a public presentation of the Phase Alternation Line to a group of experts from the European Broadcasting Union in Hannover}}</ref> The format was patented by [[Telefunken]] in December 1962, citing Bruch as inventor,<ref>{{cite web |date=7 December 2019 |title=Walter Bruch; PAL Television |url=https://www.radios-tv.co.uk/walter-bruch-pal-television/ |access-date=14 July 2021 |quote=In 1950s, when Telefunken commissioned Bruch to invent an automated differential phase correction for color television. That's why he was awarded. |archive-date=6 October 2024 |archive-url=https://web.archive.org/web/20241006175833/https://www.radios-tv.co.uk/walter-bruch-pal-television/ |url-status=live}}</ref><ref name=":0" /> and unveiled to members of the [[European Broadcasting Union]] (EBU) on 3 January 1963.<ref name=":0" /> When asked why the system was named "PAL" and not "Bruch", the inventor answered that a "Bruch system" would probably not have sold very well ("Bruch" is the German word for "breakage"<ref>{{cite web |title=English translation of 'Bruch' |url=https://www.collinsdictionary.com/dictionary/german-english/bruch |website=Collins German to English Dictionary}}</ref>).

The first broadcasts began in the [[United Kingdom]] in July 1967, followed by [[West Germany]] at the [[IFA Berlin|Berlin IFA]] on August 25.<ref name=":0">{{cite web |title=45 Years Anniversary of Walter Bruch's PAL Color Television |url=https://www.radiomuseum.org/forum/45_years_anniversary_of_walter_bruchs_pal_color_television.html |website=radiomuseum.org |access-date=15 March 2022 |archive-date=7 April 2022 |archive-url=https://web.archive.org/web/20220407083759/https://www.radiomuseum.org/forum/45_years_anniversary_of_walter_bruchs_pal_color_television.html |url-status=live}}</ref><ref name="ITU">The standard that defines the PAL system was last published by the [[International Telecommunication Union]] in 1998 and has the title [https://www.itu.int/rec/R-REC-BT.470/en ''Recommendation ITU-R BT.470, Conventional Television Systems''] {{webarchive |url=https://web.archive.org/web/20190920080738/https://www.itu.int/rec/R-REC-BT.470/en |date=20 September 2019}}</ref> The BBC channel initially using the broadcast standard was [[BBC Two|BBC2]], which had been the first UK TV service to introduce "625-lines" during 1964. The [[Netherlands]] and [[Switzerland]] started PAL broadcasts by 1968, with [[Austria]] following the next year.<ref name=":0" />

''Telefunken PALcolour 708T''<ref>{{cite web |title=Telefunken PALcolour 708 TV advert |url=https://www.radiomuseum.org/forumdata/users/4144/40_years_PAL/D_Telefunken_1967_708SM_advert.jpg |website=www.radiomuseum.org |access-date=15 March 2022 |archive-date=15 March 2022 |archive-url=https://web.archive.org/web/20220315085342/https://www.radiomuseum.org/forumdata/users/4144/40_years_PAL/D_Telefunken_1967_708SM_advert.jpg |url-status=live}}</ref> was the first PAL commercial TV set. It was followed by ''[[Loewe (electronics)|Loewe]]-Farbfernseher S 920'' and ''F 900''.<ref>{{cite web |title=Loewe-Farbfernseher S 920 & F 900 PAL TV advert |url=https://buizenradioclub.nl/media/kunena/attachments/111/Loewe2_1967.jpg |website=buizenradioclub.nl |access-date=15 March 2022 |archive-date=6 October 2024 |archive-url=https://web.archive.org/web/20241006175830/https://buizenradioclub.nl/media/kunena/attachments/111/Loewe2_1967.jpg |url-status=live}}</ref>

Telefunken was later bought by the French electronics manufacturer [[Vantiva|Thomson]]. Thomson also bought the ''Compagnie Générale de Télévision'' where [[Henri de France]] developed SECAM, the first [[European Committee for Standardization|European Standard]] for colour television. Thomson, now called Technicolour SA, also owns the [[RCA (trademark)|RCA brand]] and licences it to other companies; [[RCA|Radio Corporation of America]], the originator of that brand, created the NTSC colour TV standard before Thomson became involved.

The [[Soviet Union|Soviets]] developed two further systems, mixing concepts from PAL and SECAM, known as TRIPAL and NIIR, that never went beyond tests.<ref name=":0" />

In 1993,<ref>{{cite web |date=5 August 1993 |title=EUR-Lex – 31993D0424 – EN |url=https://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=CELEX:31993D0424:EN:HTML |website=Official Journal L 196 |pages=48–54}}</ref> an evolution of PAL aimed to improve and enhance format by allowing [[16:9 aspect ratio|16:9]] [[aspect ratio]] broadcasts, while remaining compatible with existing television receivers,<ref>{{cite web |title=Fluke PM5420 Application Note PALplus |url=https://assets.fluke.com/appnotes/it_products/B0291A-16U9509_NL_EN.pdf |url-status=dead |archive-url=https://web.archive.org/web/20160303224309/https://assets.fluke.com/appnotes/it_products/B0291A-16U9509_NL_EN.pdf |archive-date=3 March 2016 |access-date=12 January 2022 |website=assets.fluke.com}}</ref> was introduced. Named [[PALplus]], it was defined by [[International Telecommunication Union|ITU]] recommendation BT.1197-1. It was developed at the [[Technical University of Dortmund|University of Dortmund]] in [[Germany]], in cooperation with German terrestrial broadcasters and European and Japanese manufacturers. Adoption was limited to European countries.

With the introduction of [[Digital terrestrial television|digital broadcasts]] and signal sources (ex: [[DVD-Video|DVDs]], game consoles), the term PAL was used imprecisely to refer to the [[625 lines|625-line]]/50&nbsp;Hz television system in general, to differentiate from the [[525 lines|525-line]]/60&nbsp;Hz system generally used with NTSC. For example, DVDs were labelled as PAL or NTSC (referring to the line count and frame rate)<ref>{{cite web |title=What Is a NTSC Format DVD? How Can I Play a NTSC DVD in the UK Without Restriction? |url=https://www.videoconverterfactory.com/tips/ntsc-format-dvd.html |website=videoconverterfactory.com |access-date=15 March 2022 |archive-date=7 April 2022 |archive-url=https://web.archive.org/web/20220407083821/https://www.videoconverterfactory.com/tips/ntsc-format-dvd.html |url-status=live}}</ref> even though technically the discs carry neither PAL nor NTSC encoded signal. These devices would still have analog outputs (ex; [[composite video]] output), and would convert the digital signals ([[576i]] or [[480i]]) to the analog standards to assure compatibility. CCIR 625/50 and EIA 525/60 are the proper names for these (line count and field rate) standards; PAL and NTSC on the other hand are methods of encoding colour information in the signal.

== Color decoding methods ==
''<small>"PAL-D", "PAL-N", "PAL-H" and "PAL-K" designations on this section describe PAL decoding methods and are unrelated to [[Broadcast television systems#ITU standards|broadcast systems]] with similar names.<ref name=":0" /></small>''

The Telefunken licence covered any decoding method that relied on the alternating subcarrier phase to reduce phase errors, described as "''PAL-D''" for "delay", and "''PAL-N''" for "new" or "''Chrominance Lock''".<ref name=":0" />

This excluded very basic PAL decoders that relied on the human eye to average out the odd/even line phase errors, and in the early 1970s some Japanese set manufacturers developed basic decoding systems to avoid paying royalties to [[Telefunken]]. These variations are known as "''[[PAL-S]]''" (for "simple" or "Volks-PAL"),<ref name=":1">{{cite web |date=2007-07-16 |title=Tech Notes: Colour TV |url=https://www.camerasunderwater.info/engineering/tv_stds/colortv.html |url-status=dead |archive-url=https://web.archive.org/web/20070716064859/https://www.camerasunderwater.info/engineering/tv_stds/colortv.html |archive-date=2007-07-16 |access-date=2022-10-21}}</ref> operating without a delay line and suffering from the “[[Hanover bars]]” effect. An example of this solution is the ''Kuba Porta Color CK211P'' set.<ref name=":0" /> Another solution was to use a 1H [[Analog delay line|analogue delay line]] to allow decoding of only the odd or even lines. For example, the chrominance on odd lines would be switched directly through to the decoder and also be stored in the delay line. Then, on even lines, the stored odd line would be decoded again. This method (known as 'gated NTSC') was adopted by [[Sony]] on their 1970s [[Trinitron]] sets (''KV-1300UB'' to ''KV-1330UB''), and came in two versions: "''PAL-H''" and "''PAL-K''" (averaging over multiple lines).<ref name=":0" /><ref name=":1" /> It effectively treated PAL as NTSC, suffering from hue errors and other problems inherent in NTSC and required the addition of a manual [[hue]] control.

== Colour encoding ==
{{More citations needed section|date=May 2021}}

[[File:Mousepad_in.jpg|thumb|Un-decoded PAL image, showing chroma information as fine patterns [[chroma dots]] (click to zoom) overlapping the luma signal]]
[[File:Mousepad_out.jpg|thumb|Decoded PAL image, with chroma fully recovered. Some minor artifacts (see [[dot crawl]]) are present across transition areas (click to zoom).]]

Most PAL systems encode the colour information using a variant of the [[Y′UV|Y'UV]] colour space. <math>Y'</math>comprises the monochrome ''luma'' signal, with the three RGB colour channels mixed down onto two, <math>U</math> and <math>V</math>.

Like NTSC, PAL uses a [[quadrature amplitude modulation|quadrature amplitude modulated]] [[subcarrier]] carrying the ''chrominance'' information added to the luma video signal to form a [[composite video]] baseband signal. The frequency of this subcarrier is 4.43361875&nbsp;[[Hertz|MHz]] for PAL 4.43, compared to 3.579545&nbsp;MHz for NTSC 3.58. The SECAM system, on the other hand, uses a frequency modulation scheme on its two line alternate colour subcarriers 4.25000 and 4.40625&nbsp;MHz.

The name "Phase Alternating Line" describes the way that the phase of part of the colour information on the video signal is reversed with each line, which automatically corrects phase errors in the transmission of the signal by cancelling them out, at the expense of vertical frame colour resolution. Lines where the colour phase is reversed compared to NTSC are often called PAL or phase-alternation lines, which justifies one of the expansions of the acronym, while the other lines are called NTSC lines. Early PAL receivers relied on the human eye to do that cancelling; however, this resulted in a comb-like effect known as [[Hanover bars]] on larger phase errors. Thus, most receivers now use a chrominance [[Analog delay line|analogue delay line]], which stores the received colour information on each line of display; an average of the colour information from the previous line and the current line is then used to drive the [[cathode-ray tube|picture tube]]. The effect is that phase errors result in [[Colorfulness|saturation]] changes, which are less objectionable than the equivalent hue changes of NTSC. A minor drawback is that the vertical colour resolution is poorer than the NTSC system's, but since the human eye also has a colour resolution that is much lower than its brightness resolution, this effect is not visible. In any case, NTSC, PAL, and SECAM all have chrominance bandwidth (horizontal colour detail) reduced greatly compared to the luma signal.

[[File:Pal channel.svg|thumb|400px|right|Spectrum of a System I television channel with PAL]]
[[File:PAL-I.png|thumb|400px|right|RF spectrogram and [[Waterfall plot|waterfall]] of an actual PAL-I transmission with [[NICAM]]]]
[[File:PAL picture.png|thumb|400px|right|Oscillogram of composite PAL signal—one frame]]
[[File:PAL multi lines.png|thumb|400px|right|Oscillogram of composite PAL signal—several lines]]
[[File:PAL 2 lines.png|thumb|400px|right|Oscillogram of composite PAL signal—two lines]]
[[File:An interlaced PAL frame with 20ms duration.jpg|thumb|400px|right|A [[waterfall display]] showing a 20ms long interlaced PAL frame with high FFT resolution]]
[[File:PAL signal frame (20ms) and line (64µs) decoding.jpg|thumb|400px|right|Analyzing a PAL signal and decoding the 20ms frame and 64&nbsp;μs lines]]

The 4.43361875&nbsp;MHz frequency of the colour carrier is a result of 283.75 colour clock cycles per line plus a 25&nbsp;Hz offset to avoid interferences. Since the line frequency (number of lines per second) is 15625&nbsp;Hz (625&nbsp;lines ×&nbsp;50&nbsp;Hz ÷&nbsp;2), the colour [[Carrier wave|carrier frequency]] calculates as follows: 4.43361875&nbsp;MHz = 283.75 × 15625&nbsp;Hz + 25&nbsp;Hz.

The frequency 50&nbsp;Hz is the optional refresh frequency of the monitor to be able to create an illusion of motion, while 625 lines means the vertical lines or resolution that the PAL system supports.

The original colour [[Carrier wave|carrier]] is required by the colour decoder to recreate the [[Color difference|colour difference]] signals. Since the carrier is not transmitted with the video information it has to be generated locally in the receiver. In order that the [[Phase (waves)|phase]] of this locally generated signal can match the transmitted information, a 10 cycle burst of colour [[subcarrier]] is added to the video signal shortly after the line sync pulse, but before the picture information, during the so-called [[Analog television|back porch]]. This colour burst is not actually in phase with the original colour subcarrier, but leads it by 45&nbsp;degrees on the odd lines and lags it by 45&nbsp;degrees on the even lines. This [[Burst phase|swinging burst]] enables the colour decoder circuitry to distinguish the phase of the <math>R-Y'</math>vector which reverses every line.

=== PAL signal details ===
For PAL-B/G the signal has these characteristics.

{| class="wikitable"
! Parameter
! Value
|-
| Bandwidth
| {{val|5|u=MHz}}<ref name="dvd-replica_com-palnations">{{cite web |title=PGC categories – Countries using PAL standard |url=http://www.dvd-replica.com/DVD/palnations.php |url-status=dead |archive-url=https://web.archive.org/web/20090422030617/http://www.dvd-replica.com/DVD/palnations.php |archive-date=22 April 2009 |website=dvd-replica.com}}</ref>
|-
| Horizontal sync polarity
| Negative
|-
| Total time for each line
| {{val|64|ul=μs}}<ref name="pembers_freeserve_co_uk-HBI">{{cite web |title=Horizontal Blanking Interval of 405-, 525-, 625- and 819-Line Standards |url=http://www.pembers.freeserve.co.uk/World-TV-Standards/HBI.pdf |url-status=dead |archive-url=https://web.archive.org/web/20090529195823/http://www.pembers.freeserve.co.uk/World-TV-Standards/HBI.pdf |archive-date=29 May 2009}} 090426 pembers.freeserve.co.uk</ref><ref name="deetc_isel_ipl_pt-ch08">{{cite web |title=NTSC, PAL, and SECAM Overview |url=http://www.deetc.isel.ipl.pt/Analisedesinai/sm/downloads/doc/ch08.pdf |url-status=dead |archive-url=https://web.archive.org/web/20120707033657/http://www.deetc.isel.ipl.pt/Analisedesinai/sm/downloads/doc/ch08.pdf |archive-date=2012-07-07 |access-date=26 April 2009 |page=52}}</ref>
|-
| [[Analog television|Front porch]] (A)
| {{val|1.65|+0.4|-0.1|u=μs}}
|-
| Sync pulse length (B)
| {{val|4.7|0.20|u=μs}}
|-
| [[Analog television|Back porch]] (C)
| {{val|5.7|0.20|u=μs}}
|-
| Active video (D)
| {{val|51.95|+0.4|-0.1|u=μs}}
|}

(Total horizontal sync time 12.05 μs)

After 0.9 μs a {{val|2.25|0.23|u=μs}} [[Colorburst|colourburst]] of {{val|10|1}} cycles is sent. Most rise/fall times are in {{val|250|50|ul=ns}} range. Amplitude is 100% for white level, 30% for black, and 0% for sync.<ref name="pembers_freeserve_co_uk-HBI" />

The [[Composite video|CVBS]] electrical amplitude is Vpp {{val|1.0|ul=V}} and impedance of 75 [[ohm|Ω]].<ref name="thomsongrassvalley_com-3922-496-46791_s03_v01">{{cite book |url=https://wwwapps.grassvalley.com/docs/Manuals/cameras/ldk5400/3922-496-46791.s03.v01.pdf |title=LDK 5400 Triax Adapter Technical Manual |publisher=Thomson Multimedia Broadcast Solutions |year=2002 |pages= |access-date=27 February 2023 |archive-date=31 March 2023 |archive-url=https://web.archive.org/web/20230331025205/https://wwwapps.grassvalley.com/docs/Manuals/cameras/ldk5400/3922-496-46791.s03.v01.pdf |url-status=live}}</ref><!-- 2,0V Vpp at http://www.rfcandy.biz/shop/images/fq916.pdf ..? -->

[[File:Composite Video.svg|thumb|350px|right|The composite video ([[composite video|CVBS]]) signal used in systems M and N before combination with a sound carrier and [[modulation]] onto an [[Radio frequency|RF]] [[carrier signal|carrier]]]]

The vertical timings are:
{| class="wikitable"
! Parameter
! Value
|-
| Vertical lines
| 312.5 (625 total)
|-
| Vertical lines visible
| 288 (576 total)
|-
| Vertical sync polarity
| Negative (burst)
|-
| Vertical frequency
| {{val|50|u=Hz}}
|-
| Sync pulse length (F)
| {{val|0.576|ul=ms}} (burst)<ref name="pembers_freeserve_co_uk-VBI-625-PAL">{{cite web |title=Vertical Blanking Interval of 625-Line Standard (PAL Colour) |url=http://www.pembers.freeserve.co.uk/World-TV-Standards/VBI-625-PAL.pdf |url-status=dead |archive-url=https://web.archive.org/web/20160428234231/http://www.pembers.freeserve.co.uk/World-TV-Standards/VBI-625-PAL.pdf |archive-date=28 April 2016 |access-date=2015-09-03}}</ref>
|-
| Active video (H)
| 18.4<!--287.5 lines (576 PAL-B/G) --> ms
|}

(Total vertical sync time 1.6 ms)

As PAL is interlaced, every two fields are summed to make a complete picture frame.

==== Colorimetry ====
PAL colorimetry, as defined by the ITU on REC-BT.470, and based on [[CIE 1931 color space|CIE 1931]] x,y coordinates:<ref name="auto">{{cite web |title=Recommendation ITU-R BT.470-6 - Conventional Television Systems |url=https://www.itu.int/dms_pubrec/itu-r/rec/bt/R-REC-BT.470-6-199811-S!!PDF-E.pdf |access-date=19 January 2022 |archive-date=21 January 2022 |archive-url=https://web.archive.org/web/20220121001941/https://www.itu.int/dms_pubrec/itu-r/rec/bt/R-REC-BT.470-6-199811-S!!PDF-E.pdf |url-status=live}}</ref>

{| class="wikitable"
|+ PAL colorimetry
! rowspan="3" |
! rowspan="3" | Standard
! rowspan="3" | Year
! rowspan="3" | [[Standard illuminant#White points of standard illuminants|White point]]
! colspan="6" | [[Primary color|Primaries]]
! rowspan="3" | Display [[Gamma correction|gamma]] [[Transfer functions in imaging|EOTF]]
|-
! colspan="2" | Red
! colspan="2" | Green
! colspan="2" | Blue
|-
! xʀ
! yʀ
! xɢ
! yɢ
! xʙ
! yʙ
|-
! PAL
| <small>[[European Broadcasting Union|EBU]] 3213-E, [[Rec. 601|ITU-R BT.470/601 (B/G)]]</small>
| 1970
| [[Standard illuminant#Illuminant series D|D65]]
| 0.64
| 0.33
| 0.29
| 0.60
| 0.15
| 0.06
| 2.8
|-
! PAL-M
| <small>BT.470-6<ref name="auto2">{{cite web |title=Recommendation ITU-R BT.470-6 - Conventional Television Systems, p.16 |url=https://www.itu.int/dms_pubrec/itu-r/rec/bt/R-REC-BT.470-6-199811-S!!PDF-E.pdf#page=16 |access-date=14 March 2022 |archive-date=21 January 2022 |archive-url=https://web.archive.org/web/20220121001941/https://www.itu.int/dms_pubrec/itu-r/rec/bt/R-REC-BT.470-6-199811-S!!PDF-E.pdf#page=16 |url-status=live}}</ref></small>
| 1972
| [[Standard illuminant#Illuminants B and C|C]]
| 0.67
| 0.33
| 0.21
| 0.71
| 0.14
| 0.08
| 2.2
|}

The assumed [[Gamma correction|display gamma]] is defined as 2.8.<ref name="auto"/> The [[PAL-M]] system uses color primary and gamma values similar to NTSC.<ref name="auto2" /> Color is encoded using the [[Y′UV|YUV]] color space.

[[Luma (video)|Luma]] (<math>E'{\scriptstyle\text{Y}}</math>) is derived from red, green, and blue (<math>E'{\scriptstyle\text{R}}, E'{\scriptstyle\text{G}}, E'{\scriptstyle\text{B}}</math>) gamma pre-corrected (<math>E'</math>) primary signals:<!-- p20 --><ref name="deetc_isel_ipl_pt-ch08" />
* <math>E'{\scriptstyle\text{Y}}= 0.299E'{\scriptstyle\text{R}} + 0.587E'{\scriptstyle\text{G}} + 0.114E'{\scriptstyle\text{B}}</math>

<math>E'{\scriptstyle\text{U}}</math> and <math>E'{\scriptstyle\text{V}}</math> are used to transmit [[chrominance]]. Each has a typical bandwidth of 1.3&nbsp;MHz.
* <math>E'{\scriptstyle\text{U}} = 0.492(E'{\scriptstyle\text{B}}-E'{\scriptstyle\text{Y}})</math>
* <math>E'{\scriptstyle\text{V}} = 0.877(E'{\scriptstyle\text{R}}-E'{\scriptstyle\text{Y}})</math>

Composite PAL signal <math>= E'{\scriptstyle\text{Y}} + E'{\scriptstyle\text{U}} \sin (\omega t) + E'{\scriptstyle\text{V}} \cos (\omega t) +</math>timing<!-- p21 --><ref name="deetc_isel_ipl_pt-ch08" /> where <math>\omega = 2\pi F_{SC}</math>.

Subcarrier frequency <math>F_{SC}</math> is 4.43361875&nbsp;MHz (±5&nbsp;Hz) for PAL-B/D/G/H/I/N.

== PAL broadcast systems ==
The PAL colour system is usually used with a video format that has 625 lines per frame (576 visible lines, the rest being used for other information such as sync data and captioning) and a [[refresh rate]] of 50&nbsp;[[Interlaced video|interlaced]] fields per second (compatible with 25&nbsp;full frames per second), such systems being '''B''', '''G''', '''H''', '''I''', and '''N''' (see [[Broadcast television systems#ITU identification scheme|broadcast television system]]s for the technical details of each format).

This ensures video interoperability. However, as some of these standards ('''B/G/H''', '''I''' and '''D/K''') use different sound carriers (5.5&nbsp;MHz, 6.0&nbsp;MHz and 6.5&nbsp;MHz respectively), it may result in a video image without audio when viewing a signal broadcast over the air or cable. Some countries in [[Eastern Europe]] which formerly used [[SECAM]] with systems '''D''' and '''K''' have switched to PAL while leaving other aspects of their video system the same, resulting in the different sound carrier. Instead, other European countries have changed completely from SECAM-D/K to PAL-B/G.<ref name="ebu">{{cite web |title=Changes to the terrestrial television systems in Central and East European countries |url=http://tech.ebu.ch/docs/i/i033.pdf |access-date=11 September 2010 |publisher=[[European Broadcasting Union|EBU]] |archive-date=17 July 2011 |archive-url=https://web.archive.org/web/20110717135202/http://tech.ebu.ch/docs/i/i033.pdf |url-status=live}}</ref>

The PAL-N system has a different sound carrier, and also a different colour subcarrier, and decoding on incompatible PAL systems results in a black-and-white image without sound.

The PAL-M system has a different sound carrier and a different colour subcarrier, and does not use 625 lines or 50&nbsp;frames/second. This would result in no video or audio at all when viewing a European signal.

{| class="wikitable"
|+ Differences between PAL variants<ref name="auto"/>
|- style="font-weight:bold;"
! style="font-weight:normal;" |
! | PAL B
! | PAL G, H
! | PAL I
! | PAL D/K, L
! | PAL N
! | PAL M
|-
| style="font-weight:bold;" | [[ITU radio bands|Transmission band]]
| [[Very high frequency|VHF]]
| [[Ultra high frequency|UHF]]
| colspan="4" | VHF/UHF
|-
| style="font-weight:bold;" | [[Field (video)|Fields]]
| colspan="5" | 50
| 60
|-
| style="font-weight:bold;" | [[Scan lines]]
| colspan="5" | [[625 lines|625]]
| [[525 lines|525]]
|-
| style="font-weight:bold;" | [[Raster scan|Active lines]]
| colspan="5" | 576
| 480
|-
| style="font-weight:bold;" | [[Bandwidth (signal processing)|Channel bandwidth]]
| 7&nbsp;MHz
| colspan="3" | 8&nbsp;MHz
| colspan="2" | 6&nbsp;MHz
|-
| style="font-weight:bold;" | [[Video bandwidth]]
| colspan="2" | 5.0&nbsp;MHz
| 5.5&nbsp;MHz
| 6.0&nbsp;MHz
| colspan="2" | 4.2&nbsp;MHz
|-
| style="font-weight:bold;" | Vision/Sound carrier spacing
| colspan="2" | 5.5&nbsp;MHz
| 6.0&nbsp;MHz
| 6.5&nbsp;MHz
| colspan="2" | 4.5&nbsp;MHz
|-
| style="font-weight:bold;" | Colour [[Subcarrier]]
| colspan="4" | 4.43361875&nbsp;MHz
| 3.58205625&nbsp;MHz
| 3.575611&nbsp;MHz
|-
| style="font-weight:bold;" | Assumed Receiver<br />[[Gamma correction]]
| colspan="5" | 2.8
| 2.2
|}

=== System A ===
The BBC tested their pre-war (but still broadcast until 1985) [[405-line television system|405-line]] monochrome system ([[CCIR System A]]) with all three colour standards including PAL, before the decision was made to abandon 405 and transmit colour on 625/[[CCIR System I|System I]] only.

=== PAL-B/G/D/K/I ===
Many countries have turned off analogue transmissions, so the following does not apply anymore, except for using devices which output RF signals, such as [[Digital video recorder|video recorder]]s.

The majority of countries using or having used PAL have television standards with 625 lines and 50&nbsp;fields per second. Differences concern the audio carrier frequency and channel bandwidths. The variants are:
* [[CCIR System B|Standards B]]/[[CCIR System G|G]] are used in most of Western Europe, former Yugoslavia, South Asia, Thailand, Australia, and New Zealand
* [[CCIR System I|Standard I]] in the UK, Ireland, Hong Kong, South Africa, and Macau
* [[CCIR System D|Standards D]]/[[CCIR System K|K]] (along with SECAM usually) in most of Central and Eastern Europe and mainland China.

Systems B and G are similar. System B specifies 7&nbsp;MHz channel bandwidth, while System G specifies 8&nbsp;MHz channel bandwidth. Australia and China used Systems B and D respectively for VHF and UHF channels. Similarly, Systems D and K are similar except for the bands they use: System D is only used on VHF, while System K is only used on UHF. Although System I is used on both bands, it has only been used on UHF in the United Kingdom.

=== PAL-L ===
The PAL-L (Phase Alternating Line with [[CCIR System L]] broadcast system) standard uses the same video system as PAL-B/G/H (625 lines, 50&nbsp;Hz field rate, 15.625&nbsp;kHz line rate), but with a larger 6&nbsp;MHz video bandwidth rather than 5.5&nbsp;MHz and moving the audio subcarrier to 6.5&nbsp;MHz. An 8&nbsp;MHz channel spacing is used for PAL-L, to maintain compatibility with System L channel spacings.

=== PAL-N (Argentina, Paraguay and Uruguay){{Anchor|PALN}} ===
The PAL-N standard was created in [[Argentina]], through Resolution No. 100 ME/76,<ref>{{cite web |url=http://www.palermo.edu/ingenieria/TVDIGITALPOSGRADO/3.pdf |title=La TV se muda |author= |access-date=3 April 2024 |language=Spanish |archive-date=6 October 2024 |archive-url=https://web.archive.org/web/20241006175840/http://www.palermo.edu/ingenieria/TVDIGITALPOSGRADO/3.pdf |url-status=live}}</ref> which determined the creation of a study commission for a national color standard. The commission recommended using PAL under [[CCIR System N]] that [[Paraguay]] and [[Uruguay]] also used. It employs the 625 line/50&nbsp;field per second waveform of PAL-B/G, D/K, H, and I, but on a 6&nbsp;MHz channel with a chrominance subcarrier frequency of 3.582056&nbsp;MHz (917/4*H) similar to NTSC (910/4*H).<ref name="auto"/> On the studio production level, standard PAL cameras and equipment were used, with video signals then transcoded to PAL-N for broadcast.<ref>{{cite book |last1=Iazbec |url=https://books.google.com/books?id=UGTKzPeALYYC&dq=PAL-N+%28Argentina%2C+Paraguay+and+Uruguay%29&pg=PA341 |title=Estudio de las tecnicas de transcodificacion de señales de television PAL-B / PAL-N |last2=Soria |last3=Tulli |last4=Gonzalez |date=1999 |publisher=Centro de Informacion Tecnologica |volume=10 |pages=341–349 |language=es |issue=4 |access-date=4 April 2024 |archive-date=6 October 2024 |archive-url=https://web.archive.org/web/20241006175837/https://books.google.com/books?id=UGTKzPeALYYC&dq=PAL-N+%28Argentina%2C+Paraguay+and+Uruguay%29&pg=PA341#v=onepage&q=PAL-N%20(Argentina%2C%20Paraguay%20and%20Uruguay)&f=false |url-status=live}}</ref> This allows 625 line, 50&nbsp;frames per second video to be broadcast in a 6&nbsp;MHz channel, at some cost in [[Television lines|horizontal resolution]].

=== PAL-M (Brazil) ===
{{Main|PAL-M}}

In Brazil, PAL is used in conjunction with the 525 line, 60&nbsp;field/s [[CCIR System M]], using (very nearly) the NTSC colour subcarrier frequency. Exact colour subcarrier frequency of PAL-M is 3.575611&nbsp;MHz, or 227.25 times System M's horizontal scan frequency. Almost all other countries using system M use NTSC.

The PAL colour system (either baseband or with any RF system, with the normal 4.43&nbsp;MHz subcarrier unlike PAL-M) can also be applied to an NTSC-like [[525 lines|525-line]] picture to form what is often known as "PAL 60" (sometimes "PAL 60/525", "Quasi-PAL" or "Pseudo PAL"). PAL-M (a broadcast standard) however should not be confused with "PAL 60" (a video playback system—see below).

== Home devices ==

=== Multisystem TVs ===
PAL television receivers manufactured since the 1990s can typically decode all of the PAL variants except, in some cases PAL-M and PAL-N. Many such receivers can also receive Eastern European and Middle Eastern SECAM, though rarely French-broadcast SECAM (because France used a quasi-unique positive video modulation, system L) unless they are manufactured for the French market. They will correctly display plain (non-broadcast) [[Composite video|CVBS]] or [[S-Video|S-video]] SECAM signals. Many can also accept [[baseband]] NTSC-M, such as from a VCR or game console, and RF modulated NTSC with a PAL standard audio subcarrier (i.e., from a modulator), though not usually broadcast NTSC (as its 4.5&nbsp;MHz audio subcarrier is not supported). Many sets also support NTSC with a 4.43&nbsp;MHz color subcarrier (see PAL 60 on the next section).

=== VHS and DVD players ===
[[VHS]] tapes recorded from a PAL-N or a PAL-B/G, D/K, H, or I broadcast are indistinguishable because the downconverted subcarrier on the tape is the same. A VHS recorded off TV (or released) in Europe will play in colour on any PAL-N VCR and PAL-N TV in Argentina, Paraguay and Uruguay. Likewise, any tape recorded in Argentina, Paraguay or Uruguay off a PAL-N TV broadcast can be sent to anyone in European countries that use PAL (and Australia/New Zealand, etc.) and it will display in colour. This will also play back successfully in Russia and other SECAM countries, as the USSR mandated PAL compatibility in 1985—this has proved to be very convenient for video collectors.

People in Argentina, Paraguay and Uruguay usually own TV sets that also display NTSC-M, in addition to PAL-N. [[DirecTV]] also conveniently broadcasts in NTSC-M for North, Central, and South America. Most [[DVD]] players sold in Argentina, Paraguay and Uruguay also play PAL discs—however, this is usually output in the European variant (colour subcarrier frequency 4.433618&nbsp;MHz), so people who own a TV set which only works in PAL-N (plus NTSC-M in most cases) will have to watch those PAL DVD imports in black and white (unless the TV supports RGB [[SCART]]) as the colour subcarrier frequency in the TV set is the PAL-N variation, 3.582056&nbsp;MHz.

In the case that a VHS or DVD player works in PAL (and not in PAL-N) and the TV set works in PAL-N (and not in PAL), there are two options:
* images can be seen in black and white, or
* an inexpensive [[Transcoding|transcoder]] (PAL -> PAL-N) can be purchased in order to see the colours

Some DVD players (usually lesser known brands) include an internal transcoder and the signal can be output in NTSC-M, with some video quality loss due to the [[Television standards conversion|standard conversion]] from a 625/50 PAL DVD to the NTSC-M 525/60 output format. A few DVD players sold in Argentina, Paraguay and Uruguay also allow a signal output of NTSC-M, PAL, or PAL-N. In that case, a PAL disc (imported from Europe) can be played back on a PAL-N TV because there are no field/line conversions, quality is generally excellent.

Some special VHS video recorders are available which can allow viewers the flexibility of enjoying PAL-N recordings using a standard PAL (625/50&nbsp;Hz) colour TV, or even through multi-system TV sets. Video recorders like Panasonic NV-W1E (AG-W1 for the US), AG-W2, AG-W3, NV-J700AM, Aiwa HV-M110S, HV-M1U, Samsung SV-4000W and SV-7000W feature a digital TV system conversion circuitry.

=== PAL 60 === 
Many 1990s-onwards [[videocassette recorder]]s sold in Europe can play back NTSC tapes. When operating in this mode most of them do not output a true (625/50) PAL signal, but rather a hybrid consisting of the original NTSC line standard (525/60), with colour converted to PAL 4.43&nbsp;MHz (instead of 3.58 as with NTSC and South American PAL variants and with the PAL-specific phase alternation of colour difference signal between the lines) — this is known as '''"PAL 60"''' (also ''"quasi-PAL"'' or ''"pseudo-PAL"'') with "60" standing for 60&nbsp;Hz (for 525/30), instead of 50&nbsp;Hz (for 625/25).

Some video game consoles also output a signal in this mode. The [[Dreamcast]] pioneered PAL 60 with most of its games being able to play games at full speed like NTSC and without borders. [[Xbox]] and [[GameCube]] also support PAL 60 unlike PlayStation 2.<ref name="auto1">{{cite web |url=https://www.nintendolife.com/news/2010/04/talking_point_the_virtual_consoles_pal_problem |title=The Virtual Console's PAL Problem |date=15 April 2010 |access-date=27 July 2021 |archive-date=27 July 2021 |archive-url=https://web.archive.org/web/20210727164622/https://www.nintendolife.com/news/2010/04/talking_point_the_virtual_consoles_pal_problem |url-status=live}}</ref> The [[PlayStation 2]] did not actually offer a true PAL 60 mode; while many PlayStation 2 games did offer a "PAL 60" mode as an option, the console would in fact generate an NTSC signal during 60&nbsp;Hz operation.

Most newer television sets can display a "PAL 60" signal correctly, but some will only do so (if at all) in black and white and/or with flickering/foldover at the bottom of the picture, or picture rolling (however, many old TV sets can display the picture properly by means of adjusting the V-Hold and V-Height knobs—assuming they have them). Some TV tuner cards or video capture cards will support this mode (although software/driver modification can be required and the manufacturers' specs may be unclear).

Some DVD players offer a choice of PAL vs NTSC output for NTSC discs.<ref>{{cite web |url=https://www.amigaforever.com/kb/16-111 |title=Playback of NTSC Videos on PAL Equipment |access-date=29 June 2019 |archive-date=6 October 2024 |archive-url=https://web.archive.org/web/20241006175837/https://www.amigaforever.com/kb/16-111 |url-status=live}}</ref>

== PAL vs. NTSC ==
PAL usually has 576 visible lines compared with 480 lines with [[NTSC]], meaning that PAL has a 20% higher resolution, in fact it even has a higher resolution than [[Enhanced-definition television|Enhanced Definition]] standard (852x480). Most TV output for PAL and NTSC use interlaced frames meaning that even lines update on one field and odd lines update on the next field. Interlacing frames gives a smoother motion with half the frame rate. [[NTSC]] is used with a [[frame rate]] of [[Interlaced video|60i]] or [[Progressive scan|30p]] whereas PAL generally uses [[Interlaced video|50i]] or [[Progressive scan|25p]]; both use a high enough [[frame rate]] to give the illusion of fluid motion. This is due to the fact that NTSC is generally used in countries with a [[utility frequency]] of 60&nbsp;Hz and PAL in countries with 50&nbsp;Hz, although there are many exceptions.

Both PAL and NTSC have a higher frame rate than film which uses 24&nbsp;frames per second. PAL has a closer frame rate to that of film, so most films are sped up 4% to play on PAL systems, shortening the runtime of the film and, without adjustment, slightly raising the pitch of the audio track in order to, in the case of VHS tapes and DVDs, make room for more local content made in the country (UK, Australia etc). Film conversions for NTSC instead use [[Three-two pull down|3:2 pull down]] to spread the 24&nbsp;frames of film across 60&nbsp;interlaced fields. This maintains the runtime of the film and preserves the original audio, but may cause worse interlacing artefacts during fast motion.

NTSC receivers have a [[tint control]] to perform colour correction manually. If this is not adjusted correctly, the colours may be faulty. The PAL standard automatically cancels [[hue]] errors by phase reversal, so a tint control is unnecessary yet Saturation control can be more useful. Chrominance phase errors in the PAL system are cancelled out using a 1H delay line resulting in lower saturation, which is much less noticeable to the eye than NTSC hue errors.

However, the alternation of colour information—[[Hanover bars]]—can lead to picture grain on pictures with extreme phase errors even in PAL systems, if decoder circuits are misaligned or use the simplified decoders of early designs (typically to overcome royalty restrictions). This effect will usually be observed when the transmission path is poor, typically in built up areas or where the terrain is unfavourable. The effect is more noticeable on UHF than VHF signals as VHF signals tend to be more robust. In most cases such extreme phase shifts do not occur.

PAL and NTSC have slightly divergent [[RGB color spaces#RGB color space specifications|colour space]]s, but the colour decoder differences here are ignored.

Outside of film and TV broadcasts, the differences between PAL and NTSC when used in the context of [[Video game|video games]] were quite dramatic. For comparison, the NTSC standard is 60&nbsp;fields/30&nbsp;frames per second while PAL is 50&nbsp;fields/25&nbsp;frames per second. To avoid timing problems or unfeasible code changes, games were slowed down by approximately 16.7%. This has led to games ported over to PAL regions being historically known for their inferior speed and frame rates compared to their NTSC counterparts, especially when they are not properly optimized for PAL standards.

[[Full-motion video|Full motion video]] rendered and encoded at 30&nbsp;frames per second by the Japanese/US (NTSC) developers were often down-sampled to 25&nbsp;frames per second or considered to be 50&nbsp;frames per second video for PAL release—usually by means of [[Three-two pull down|3:2 pull-down]], resulting in motion [[Telecine#Telecine judder|judder]]. In addition, the increased resolution of PAL was often not utilised at all during conversion, creating a pseudo-letterbox effect with borders on the top and bottom of the screen, looking similar to 14:9 letterbox. This leaves the graphics with a slightly squashed look due to an incorrect aspect ratio caused by the borders.

These practices were prevalent in previous generations, especially during the [[Third generation of video game consoles|8-bit]] and [[Fourth generation of video game consoles|16-bit]] era of video games where 2D graphics were the norm at that time. The gameplay of many games with an emphasis on speed, such as the original ''[[Sonic the Hedgehog (1991 video game)|Sonic the Hedgehog]]'' for the [[Sega Genesis|Sega Genesis (Mega Drive)]], suffered in their PAL incarnations.

Starting with the [[Sixth generation of video game consoles|sixth generation]] of video games, game consoles started to offer true 60&nbsp;Hz modes in games ported to PAL regions. The [[Dreamcast]] was the first to offer a true "PAL 60" mode, with many games made for the system in PAL regions being closely on-par with their NTSC counterparts in terms of speed and frame rates using "PAL 60" modes. The [[Xbox (console)|Xbox]] and [[GameCube]] also featured "PAL 60" modes in games made for the region as well. The only lone exception was the [[PlayStation 2]], where games ported over to PAL regions are oftentimes (but not always) running in 50&nbsp;Hz modes. PAL region games supporting 60&nbsp;Hz modes for the PlayStation 2 also requires a display with NTSC output unless [[Component video#RGB analog component video|RGB]] or [[Component video#Luma-based analog component video|component]] connections were used, since these allowed for colour outputs without the need for NTSC or PAL colour encoding. Otherwise, the games would display in monochrome on PAL-only displays.

The problems usually associated with PAL region video games are not necessarily encountered in Brazil with the PAL-M standard used in that region, since its video system uses an identical number of visible lines and refresh rate as NTSC but with a slightly different colour encoding frequency based on PAL, modified for use with the [[CCIR System M]] broadcast television system.

== PAL vs. SECAM ==
The [[SECAM]] patents predate those of PAL by several years (1956 vs. 1962). Its creator, Henri de France, in search of a response to known NTSC [[hue]] problems, came up with ideas that were to become fundamental to both European systems, namely:
# colour information on two successive TV lines is very similar and vertical resolution can be halved without serious impact on perceived visual quality
# more robust colour transmission can be achieved by spreading information on two TV lines instead of just one
# information from the two TV lines can be recombined using a delay line.

SECAM applies those principles by transmitting alternately only one of the U and V components on each TV line, and getting the other from the delay line. QAM is not required, and [[frequency modulation]] of the subcarrier is used instead for additional robustness (sequential transmission of U and V was to be reused much later in Europe's last "analog" video systems: the MAC standards).

SECAM is free of both hue and saturation errors. It is not sensitive to phase shifts between the colour burst and the chrominance signal, and for this reason was sometimes used in early attempts at colour video recording, where tape speed fluctuations could get the other systems into trouble. In the receiver, it did not require a quartz crystal (which was an expensive component at the time) and generally could do with lower accuracy delay lines and components.

SECAM transmissions are more robust over longer distances than NTSC or PAL. However, owing to their FM nature, the colour signal remains present, although at reduced amplitude, even in monochrome portions of the image, thus being subject to stronger cross colour.

One serious drawback for studio work is that the addition of two SECAM signals does not yield valid colour information, due to its use of frequency modulation. It was necessary to demodulate the FM and handle it as AM for proper mixing, before finally remodulating as FM, at the cost of some added complexity and signal degradation. In its later years, this was no longer a problem, due to the wider use of component and digital equipment.

PAL can work without a delay line ([[PAL-S]]), but this configuration, sometimes referred to as "poor man's PAL", could not match SECAM in terms of picture quality. To compete with it at the same level, it had to make use of the main ideas outlined above, and as a consequence PAL had to pay licence fees to SECAM. Over the years, this contributed significantly to the estimated 500 million francs gathered by the SECAM patents (for an initial 100 million francs invested in research).<ref>{{cite web |url=http://www.ebha.org/ebha2007/pdf/Gaillard.pdf |title="The CCIR, the standards and the TV sets' market in France" (section III.1) |access-date=28 February 2017 |archive-date=20 October 2016 |archive-url=https://web.archive.org/web/20161020094732/http://www.ebha.org/ebha2007/pdf/Gaillard.pdf |url-status=live}}</ref>

Hence, PAL could be considered as a hybrid system, with its signal structure closer to NTSC, but its decoding borrowing much from SECAM.

There were initial specifications to use colour with the French 819 line format (system E). However, "SECAM E" only ever existed in development phases. Actual deployment used the 625 line format. This made for easy interchange and conversion between PAL and SECAM in Europe. Conversion was often not even needed, as more and more receivers and VCRs became compliant with both standards, helped in this by the common decoding steps and components. When the [[SCART]] plug became standard, it could take RGB as an input, effectively bypassing all the colour coding formats' peculiarities.

When it comes to home VCRs, all video standards use what is called "colour under" format. Colour is extracted from the high frequencies of the video spectrum, and moved to the lower part of the spectrum available from tape. Luma then uses what remains of it, above the colour frequency range. This is usually done by heterodyning for PAL (as well as NTSC). But the FM nature of colour in SECAM allows for a cheaper trick: division by 4 of the subcarrier frequency (and multiplication on replay). This became the standard for SECAM VHS recording in France. Most other countries kept using the same heterodyning process as for PAL or NTSC and this is known as MESECAM recording (as it was more convenient for some Middle East countries that used both PAL and SECAM broadcasts).

Another difference in colour management is related to the proximity of successive tracks on the tape, which is a cause for chroma crosstalk in PAL. A cyclic sequence of 90° chroma phase shifts from one line to the next is used to overcome this problem. This is not needed in SECAM, as FM provides sufficient protection.

Regarding early (analogue) videodiscs, the established Laserdisc standard supported only NTSC and PAL. However, a different optical disc format, the Thomson transmissive optical disc made a brief appearance on the market. At some point, it used a modified SECAM signal (single FM subcarrier at 3.6&nbsp;MHz<ref>"Les Videodisques", Georges Broussaud (head/member of development team), editions Masson</ref>). The media's flexible and transmissive material allowed for direct access to both sides without flipping the disc, a concept that reappeared in multi-layered DVDs about fifteen years later.

== Countries and territories that are using or once used PAL ==
{{See also|DVB-T#Countries and territories using DVB-T}}

Below are lists of countries and territories that used or once used the PAL system. Many of these have converted or are converting PAL to [[DVB-T]] (most countries), [[DVB-T2]] (most countries), [[Digital Terrestrial Multimedia Broadcast|DTMB]] (China, Hong Kong and Macau) or [[ISDB-T International|ISDB-Tb]] (Sri Lanka, Maldives, Botswana, Brazil, Argentina, Paraguay and Uruguay).

A legacy list of PAL users in 1998 is available on ''Recommendation ITU-R BT.470-6 - Conventional Television Systems, Appendix 1 to Annex 1''.<ref>{{cite book |url=https://www.itu.int/dms_pubrec/itu-r/rec/bt/R-REC-BT.470-6-199811-S!!PDF-E.pdf |title=Recommendation ITU-R BT.470-6 - Conventional Television Systems |publisher=ITU Radiocommunication Assembly |year=1998 |pages=29–34 |access-date=19 January 2022 |archive-date=21 January 2022 |archive-url=https://web.archive.org/web/20220121001941/https://www.itu.int/dms_pubrec/itu-r/rec/bt/R-REC-BT.470-6-199811-S!!PDF-E.pdf |url-status=live}}</ref>

=== Using PAL B, D, G, H, K or I ===
<!--This is information that is for sure a list in nature. Converting it to prose would obfuscate it and make it harder to read, use, edit and update. Please do not tag this genuine list for conversion to "prose"-->

* {{flag|Afghanistan}} (used SECAM)<ref name="HegartyPhelan1998">{{cite book |author1=Michael Hegarty |url=https://books.google.com/books?id=5YjHecPlPS8C&pg=PA260 |title=Classrooms for Distance Teaching and Learning: A Blueprint |author2=Anne Phelan |author3=Lisa Kilbride |date=1 January 1998 |publisher=[[Leuven University Press]] |isbn=978-90-6186-867-5 |pages=260– |access-date=16 December 2015 |archive-date=6 October 2024 |archive-url=https://web.archive.org/web/20241006175837/https://books.google.com/books?id=5YjHecPlPS8C&pg=PA260#v=onepage&q&f=false |url-status=live}}</ref>
* {{flag|Algeria}}
* {{flag|Angola}}<ref name="HegartyPhelan1998"/>
* {{flag|Armenia}}
* {{flag|Bahrain}} (DVB-T introduction in assessment)<ref name="HegartyPhelan1998"/>
* {{flag|Bhutan}}<ref name="HegartyPhelan1998"/>
* {{flag|Botswana}}<ref name="HegartyPhelan1998"/>
* {{flag|British Indian Ocean Territory}}<ref name="HegartyPhelan1998"/>
* {{flag|Cameroon}}<ref name="HegartyPhelan1998"/>
* {{flag|Cape Verde}}<ref name="HegartyPhelan1998"/>
* {{flag|Christmas Island}}
* {{flag|Comoros}}
* {{flag|Cook Islands}} (see New Zealand)
* {{flag|Djibouti}}<ref name="HegartyPhelan1998"/>
* {{flag|Equatorial Guinea}}<ref name="HegartyPhelan1998"/>
* {{flag|Eritrea}}<ref name="HegartyPhelan1998"/>
* {{flag|Eswatini}}<ref name="HegartyPhelan1998"/>
* {{flag|Ethiopia}}<ref name="HegartyPhelan1998"/>
* {{flag|Falkland Islands}} (UHF only)<ref name="HegartyPhelan1998"/>
* {{flag|Fiji}}
* {{flag|Gambia}}<ref name="HegartyPhelan1998"/>
* {{flag|Guinea-Bissau}}<ref name="HegartyPhelan1998"/>
* {{flag|Iraq}}<ref name="HegartyPhelan1998"/> (DVB-T introduction in assessment)
* {{flag|Jordan}}<ref name="shop.sandbag.uk.com">{{cite web |title=PAL / NTSC / SECAM countries list |url=http://shop.sandbag.uk.com/OneGiantLeap/PALNTSCInfo.html |url-status=dead |archive-url=https://web.archive.org/web/20160221173323/http://shop.sandbag.uk.com/OneGiantLeap/PALNTSCInfo.html |archive-date=21 February 2016 |access-date=2017-12-09}}</ref> (DVB-T introduction in assessment)
* {{flag|Kiribati}}<ref name="HegartyPhelan1998"/>
* {{flag|Kuwait}}<ref name="HegartyPhelan1998"/>
* {{flag|Laos}} (Once experimented in PAL-M)<ref name="HegartyPhelan1998"/>
* {{flag|Lebanon}} (uses PAL for Lebanese channels)
* {{flag|Lesotho}}<ref name="HegartyPhelan1998"/>
* {{flag|Liberia}}<ref name="HegartyPhelan1998"/>
* {{flag|Libya}}
* {{flag|Malawi}}<ref name="HegartyPhelan1998"/>
* {{flag|Maldives}}<ref name="HegartyPhelan1998"/>
* {{flag|Mauritius}}
* {{flag|Mozambique}}<ref name="HegartyPhelan1998"/>
* {{flag|Myanmar}}<ref name="HegartyPhelan1998"/> (Unofficially, only for non-terrestrial)
* {{flag|Nauru}}<ref name="HegartyPhelan1998"/>
* {{flag|Nepal}}<ref name="HegartyPhelan1998"/>
* {{flag|Niue}}<ref name="HegartyPhelan1998"/>
* {{flag|Norfolk Island}} (see Australia)
* {{flag|North Korea}} (used SECAM until 1990s)<ref name="HegartyPhelan1998"/>
* {{flag|Oman}} (DVB-T introduction in assessment)<ref name="HegartyPhelan1998"/>
* {{flag|Palestine}} (DVB-T introduction in assessment)
* {{flag|Papua New Guinea}}<ref name="HegartyPhelan1998"/>
* {{flag|Saint Helena, Ascension and Tristan da Cunha}} (Two PAL-I analogue TV services operated by BFBS)
* {{flag|Samoa}}<ref name="HegartyPhelan1998"/>
* {{flag|São Tomé and Príncipe}}
* {{flag|Seychelles}}<ref name="HegartyPhelan1998"/>
* {{flag|Sierra Leone}}<ref name="HegartyPhelan1998"/>
* {{flag|Solomon Islands}}
* {{flag|Somalia}}<ref name="HegartyPhelan1998"/>
* {{flag|South Africa}} (Simulcast in DVB-T)
* {{flag|South Sudan}}
* {{flag|Sri Lanka}}<ref name="HegartyPhelan1998"/>
* {{flag|Sudan}}<ref name="HegartyPhelan1998"/>
* {{flag|Syria|1932}} (along with SECAM)<ref name="HegartyPhelan1998"/>
* {{flag|Timor-Leste}}
* {{flag|Tonga}}<ref name="HegartyPhelan1998"/> (Simulcast in DVB-T)
* {{flag|Turkey}}
* {{flag|Tuvalu}}<ref name="HegartyPhelan1998"/>
* {{flag|Uganda}}<ref name="HegartyPhelan1998"/>
* {{flag|Vanuatu}}<ref name="HegartyPhelan1998"/>
* {{flag|Yemen}}<ref name="HegartyPhelan1998"/> (DVB-T introduction in assessment)
* {{flag|Zimbabwe}}<ref name="HegartyPhelan1998"/>

=== PAL-M ===
* {{flag|Brazil}}{{efn|Simulcast in ISDB-Tb started on 2 December 2007. PAL broadcasting in its final stages of abandonment, the complete shutdown is scheduled to 2025.}}

=== PAL-N ===
* {{flag|Argentina}}{{efn|Simulcast in ISDB-Tb started on 28 August 2008. PAL broadcasting in its final stages of abandonment, the complete shutdown is scheduled to 2025.}}
* {{flag|Paraguay}} (Simulcast in ISDB-Tb)
* {{flag|Uruguay}} (Simulcast in ISDB-Tb)

=== Countries and territories that have ceased using PAL ===
The following countries and territories no longer use PAL for terrestrial broadcasts, and are in process of converting from PAL to [[DVB-T]]/[[DVB-T2|T2]], [[DTMB]] or [[ISDB#ISDB-T|ISDB-T]].

{| class="wikitable sortable"
! Country
! Switched to
! Switchover completed
|-
| {{ALB}}
| DVB-T2
| <span style="display:none">2019-10-01</span>1 October 2019
|-
| {{AND}}
| DVB-T
| <span style="display:none">2007-09-25</span>25 September 2007
|-
| {{AUS}}
| DVB-T
| <span style="display:none">2013-12-10</span>10 December 2013
|-
| {{AUT}}
| DVB-T and DVB-T2
| <span style="display:none">2010-06-07</span>7 June 2011
|-
| {{AZE}}
| DVB-T
| <span style="display:none">2015-06-17</span>17 June 2015
|-
| {{flag|Bangladesh}}
| DVB-T
| <span style="display:none">2024-11-30</span>30 November 2024
|-
| {{BEL}}
| DVB-T
| <span style="display:none">2010-03-01</span>1 March 2010
|-
| {{flag|Bosnia and Herzegovina}}
| DVB-T
| <span style="display:none">2024-12-31</span>31 December 2024
|-
| {{BRN}}
| DVB-T
| <span style="display:none">2015-01-01</span>1 January 2015
|-
| {{BUL}}
| DVB-T
| <span style="display:none">2013-09-30</span>30 September 2013
|-
| {{CAM}}
| DVB-T2
| <span style="display:none">2015-01-01</span>1 January 2015
|-
| {{CHN}}
| [[Digital Terrestrial Multimedia Broadcast|DTMB]]
| <span style="display:none">2021-03-31</span>31 March 2021
|-
| {{HRV}}
| DVB-T2
| <span style="display:none">2020-11-12</span>12 November 2020<ref>{{cite web |title=Prijelaz na DVB-T2 TV signal s HEVC (H.265) sažimanjem {{!}} OIV digitalni signali i mreže |url=https://gledajbezbrige.oiv.hr/dvb-t2-prijelaz/ |access-date=2024-01-02 |website=gledajbezbrige.oiv.hr |language=hr |archive-date=2 January 2024 |archive-url=https://web.archive.org/web/20240102104019/https://gledajbezbrige.oiv.hr/dvb-t2-prijelaz/ |url-status=live}}</ref>
|-
| {{CYP}}
| DVB-T
| <span style="display:none">2011-07-01</span>1 July 2011
|-
| {{CZE}}
| DVB-T and DVB-T2
| <span style="display:none">2012-06-30</span>30 June 2012
|-
| {{DEN}}
| DVB-T and DVB-T2
| <span style="display:none">2009-11-01</span>1 November 2009
|-
| {{flag|Egypt}}
| DVB-T
| <span style="display:none">2024-09-30</span>30 September 2024
|-
| {{EST}}
| DVB-T
| <span style="display:none">2010-07-01</span>1 July 2010
|-
| {{FRO}}
| DVB-T
| <span style="display:none">2002–12</span>December 2002
|-
| {{FIN}}
| DVB-T and DVB-T2
| <span style="display:none">2007-09-01</span>1 September 2007
|-
| {{GEO}}
| DVB-T
| <span style="display:none">2015-07-01</span>1 July 2015
|-
| {{GER}}
| DVB-T and DVB-T2
| <span style="display:none">2009-06-04</span>4 June 2009
|-
| {{GHA}}
| DVB-T2
| <span style="display:none">2015-06</span>June 2015
|-
| {{GRE}}
| DVB-T
| <span style="display:none">2015-02-05</span>6 February 2015
|-
| {{GIB}}
| DVB-T
| <span style="display:none">2012-12-31</span>31 December 2012
|-
| {{GGY}}
| DVB-T
| <span style="display:none">2010-11-17</span>17 November 2010
|-
| {{HKG}}
| DTMB
| <span style="display:none">2020-12-01</span>1 December 2020
|-
| {{HUN}}
| DVB-T and DVB-T2
| <span style="display:none">2013-10-31</span>31 October 2013
|-
| {{ISL}}
| DVB-T and DVB-T2
| <span style="display:none">2015-02-02</span>2 February 2015
|-
| {{IND}}
| DVB-T
| <span style="display:none">2015-03-31</span>31 March 2015
|-
| {{INA}}
| DVB-T2
| <span style="display:none">2023-08-12</span>12 August 2023<ref>{{cite web |title=Siaran TV Analog Disetop di Seluruh RI 12 Agustus 2023 |url=https://www.detik.com/jabar/berita/d-6870993/siaran-tv-analog-disetop-di-seluruh-ri-12-agustus-2023 |access-date=22 September 2023 |website=detik.com |archive-date=15 October 2023 |archive-url=https://web.archive.org/web/20231015124141/https://www.detik.com/jabar/berita/d-6870993/siaran-tv-analog-disetop-di-seluruh-ri-12-agustus-2023 |url-status=live}}</ref>
|-
| {{IRN}}
| DVB-T
| <span style="display:none">2014-12-19</span>19 December 2014
|-
| {{IRL}}
| DVB-T
| <span style="display:none">2012-10-24</span>24 October 2012
|-
| {{IMN}}
| DVB-T
| <span style="display:none">2012-10-24</span>24 October 2012
|-
| {{ISR}}
| DVB-T and DVB-T2
| <span style="display:none">2011-06-13</span>13 June 2011
|-
| {{ITA}}
| DVB-T
| <span style="display:none">2012-07-04</span>4 July 2012
|-
| {{JEY}}
| DVB-T
| <span style="display:none">2010-11-17</span>17 November 2010
|-
| {{KEN}}
| DVB-T
| <span style="display:none">2015-03</span>March 2015
|-
| {{LAT}}
| DVB-T
| <span style="display:none">2010-06-01</span>1 June 2010
|-
| {{LTU}}
| DVB-T
| <span style="display:none">2012-10-29</span>29 October 2012
|-
| {{LUX}}
| DVB-T
| <span style="display:none">2006-09-01</span>1 September 2006
|-
| {{MAC}}
| DTMB
| <span style="display:none">2023-06-30</span>30 June 2023<ref>{{cite web |title=TDM to switch off analogue television transmission system |url=https://www.tdm.com.mo/en/news-detail/850844 |access-date=13 July 2023 |website=TDM |archive-date=13 July 2023 |archive-url=https://web.archive.org/web/20230713035410/https://www.tdm.com.mo/en/news-detail/850844 |url-status=live}}</ref>
|-
| {{MKD}}
| DVB-T
| <span style="display:none">2013-05-31</span>31 May 2013
|-
| {{MAS}}
| DVB-T2
| <span style="display:none">2019-10-31</span>31 October 2019
|-
| {{MLT}}
| DVB-T
| <span style="display:none">2011-10-31</span>31 October 2011
|-
| {{MON}}
| DVB-T
| <span style="display:none">2011-05-24</span>24 May 2011
|-
| {{flag|Moldova}}
| DVB-T
| <span style="display:none">2024-12-31</span>31 December 2024
|-
| {{flag|Mongolia}}
| DVB-T
| <span style="display:none">2024-12-20</span>20 December 2024
|-
| {{MNE}}
| DVB-T
| <span style="display:none">2015-06-17</span>17 June 2015
|-
| {{NAM}}
| DVB-T
| <span style="display:none">2014-09-13</span>13 September 2014
|-
| {{NED}}
| DVB-T
| <span style="display:none">2006-12-14</span>14 December 2006
|-
| {{NZL}}
| DVB-T
| <span style="display:none">2013-12-01</span>1 December 2013
|-
| {{flag|Nigeria}}
| DVB-T
| <span style="display:none">2024-12-15</span>15 December 2024
|-
| {{NOR}}
| DVB-T
| <span style="display:none">2009-12</span>December 2009<ref>{{cite web |date=17 March 2020 |title=TV og radio |url=https://www.nkom.no/fritid/digital-radio/digitalt-bakkenett/digitalt-bakkenett-i-norge |access-date=28 April 2023 |archive-date=8 December 2016 |archive-url=https://web.archive.org/web/20161208003447/http://www.nkom.no/fritid/digital-radio/digitalt-bakkenett/digitalt-bakkenett-i-norge |url-status=live}}</ref>
|-
| {{POL}}
| DVB-T2<ref>{{cite web |title=Zmiana standardu nadawania kanałów TVP na DVB-T2/HEVC - Nowa telewizja cyfrowa (DVB-T2) - Portal Gov.pl |url=https://www.gov.pl/web/dvbt2/zmiana-standardu-nadawania-kanalow-tvp-na-dvb-t2hevc2 |access-date=2024-08-08 |website=Nowa telewizja cyfrowa (DVB-T2) |language=pl-PL |archive-date=6 October 2024 |archive-url=https://web.archive.org/web/20241006175838/https://www.gov.pl/web/dvbt2/zmiana-standardu-nadawania-kanalow-tvp-na-dvb-t2hevc2 |url-status=live}}</ref>
| <span style="display:none">2013-07-23</span>23 July 2013
|-
| {{POR}}
| DVB-T
| <span style="display:none">2012-04-26</span>26 April 2012
|-
| {{QAT}}
| DVB-T and DVB-T2
| <span style="display:none">2012-02-13</span>13 February 2012
|-
| {{ROM}}
| DVB-T2
| <span style="display:none">2016-12-31</span>31 December 2016
|-
| {{RWA}}
| DVB-T
| <span style="display:none">2014-03</span>March 2014
|-
| {{SMR}}
| DVB-T
| <span style="display:none">2010-12-02</span>2 December 2010
|-
| {{KSA}}
| DVB-T and DVB-T2
| <span style="display:none">2012-02-13</span>13 February 2012
|-
| {{SRB}}
| DVB-T2
| <span style="display:none">2015-06-07</span>7 June 2015
|-
| {{SIN}}
| DVB-T2
| <span style="display:none">2019-01-02</span>2 January 2019
|-
| {{SVK}}
| DVB-T
| <span style="display:none">2012-12-31</span>31 December 2012
|-
| {{SLO}}
| DVB-T
| <span style="display:none">2010-12-01</span>1 December 2010
|-
| {{ESP}}
| DVB-T and DVB-T2
| <span style="display:none">2010-04-03</span>3 April 2010
|-
| {{SWE}}
| DVB-T and DVB-T2
| <span style="display:none">2007-10-29</span>29 October 2007
|-
| {{SUI}}
| DVB-T
| <span style="display:none">2007-11-26</span>26 November 2007
|-
| {{TAN}}
| DVB-T
| <span style="display:none">2014-07</span>July 2014
|-
| {{THA}}
| DVB-T2
| <span style="display:none">2020-03-26</span>26 March 2020
|-
| {{UKR}}
| DVB-T and DVB-T2
| <span style="display:none">2016-12-31</span>31 December 2016
|-
| {{UAE}}
| DVB-T and DVB-T2
| <span style="display:none">2012-02-13</span>13 February 2012
|-
| {{UK}}
| [[DVB-T]] (SD) and [[DVB-T2]] (HD)
| <span style="display:none">2012-10-24</span>24 October 2012
|-
| {{VIE}}
| DVB-T2
| <span style="display:none">2020-12-28</span>28 December 2020
|-
| {{ZAM}}
| DVB-T2
| <span style="display:none">2014-12-31</span>31 December 2014
|}

== See also ==
* [[Prewar television stations]]
* [[Broadcast-safe]]
* [[D-1 (Sony)|D1 SMPTE]]
* [[D-2 (video)]]
== Notes ==
{{notelist}}

== References ==
{{reflist|30em}}

== External links ==
{{Commons category|PAL}}

* [https://archive.today/20121205005309/http://www.paradiso-design.net/videostandards_en.html Review of the different refresh rates of PAL, NTSC and motion picture films]
* [https://web.archive.org/web/20190709033551/http://www.radios-tv.co.uk/Pembers/World-TV-Standards/Colour-Standards.html#Top World TV standards]

{{Video formats}}
{{colour space}}
{{Analogue TV transmitter topics}}
{{Telecommunications}}

[[Category:ITU-R recommendations]]
[[Category:Television technology]]
[[Category:Television terminology]]
[[Category:Television transmission standards]]
[[Category:Video formats]]
[[Category:German inventions]]
[[Category:1963 introductions]]