Hawk-Eye is a
computer vision system used in numerous sports such as
cricket
Cricket is a bat-and-ball game played between two teams of eleven players on a field at the centre of which is a pitch with a wicket at each end, each comprising two bails balanced on three stumps. The batting side scores runs by striki ...
,
tennis
Tennis is a racket sport that is played either individually against a single opponent ( singles) or between two teams of two players each ( doubles). Each player uses a tennis racket that is strung with cord to strike a hollow rubber ball ...
,
Gaelic football
Gaelic football ( ga, Peil Ghaelach; short name '), commonly known as simply Gaelic, GAA or Football is an Irish team sport. It is played between two teams of 15 players on a rectangular grass pitch. The objective of the sport is to score by kic ...
,
badminton
Badminton is a racquet sport played using racquets to hit a shuttlecock across a net. Although it may be played with larger teams, the most common forms of the game are "singles" (with one player per side) and "doubles" (with two players pe ...
,
hurling
Hurling ( ga, iománaíocht, ') is an outdoor team game of ancient Gaelic Irish origin, played by men. One of Ireland's native Gaelic games, it shares a number of features with Gaelic football, such as the field and goals, the number of p ...
,
rugby union
Rugby union, commonly known simply as rugby, is a close-contact team sport that originated at Rugby School in the first half of the 19th century. One of the two codes of rugby football, it is based on running with the ball in hand. In its m ...
,
association football
Association football, more commonly known as football or soccer, is a team sport played between two teams of 11 players who primarily use their feet to propel the ball around a rectangular field called a pitch. The objective of the game is ...
and
volleyball
Volleyball is a team sport in which two teams of six players are separated by a net. Each team tries to score points by grounding a ball on the other team's court under organized rules. It has been a part of the official program of the Summ ...
, to visually track the trajectory of the ball and display a profile of its statistically most likely path as a moving image. The onscreen representation of the trajectory results is called Shot Spot.
The
Sony
, commonly stylized as SONY, is a Japanese multinational conglomerate corporation headquartered in Minato, Tokyo, Japan. As a major technology company, it operates as one of the world's largest manufacturers of consumer and professional ...
-owned Hawk-Eye system was developed in the United Kingdom by Paul Hawkins. The system was originally implemented in 2000 for television purposes in cricket. The system works via six (sometimes seven) high-performance cameras, normally positioned on the underside of the stadium roof, which track the ball from different angles. The video from the six cameras is then
triangulated and combined to create a three-dimensional representation of the ball's trajectory. Hawk-Eye is not infallible, but is advertised to be accurate to within 3.6 millimetres and generally trusted as an impartial second opinion in sports. It has been accepted by governing bodies in tennis, cricket and association football as a means of adjudication with different number of cameras depending on the sport. Hawk-Eye is used for the Challenge System since 2006 in tennis and
Decision Review System
The Decision Review System (DRS), formerly known as the Umpire Decision Review System (UDRS), is a technology-based system used in cricket to assist the match officials in their decision-making. On-field Umpire (cricket), umpires may choose to co ...
in cricket since 2009. The system was rolled out for the
2013–14 Premier League season as a means of
goal-line technology In many outdoor ball sports, a goal line is a line in front of goal post and which a team attempts to advance the ball or puck towards to score a goal or points. In particular, see:
* Football pitch
A football pitch (also known as soccer fiel ...
. In December 2014, it was also adopted for the
2015–16 Bundesliga season.
Method of operation
All Hawk-Eye systems are based on the principles of
triangulation using visual images and timing data provided by a number of high-speed video cameras located at different locations and angles around the area of play.
For tennis there are 10 cameras. The system rapidly processes the video feeds from the cameras and ball tracker. A data store contains a predefined model of the playing area and includes data on the rules of the game.
In each frame sent from each camera, the system identifies the group of pixels which corresponds to the image of the ball. It then calculates for each frame the position of the ball by comparing its position on at least two of the physically separate cameras at the same instant in time. A succession of frames builds up a record of the path along which the ball has travelled. It also "predicts" the future flight path of the ball and where it will interact with any of the playing area features already programmed into the database. The system can also interpret these interactions to decide infringements of the rules of the game.
The system generates a graphic image of the ball path and playing area, which means that information can be provided to judges, television viewers or coaching staff in
near real-time
Real-time computing (RTC) is the computer science term for hardware and software systems subject to a "real-time constraint", for example from event to system response. Real-time programs must guarantee response within specified time constrai ...
.
The tracking system is combined with a back-end database and archiving capabilities so that it is possible to extract and analyse trends and statistics about individual players, games, ball-to-ball comparisons, etc.
History
Hawk-Eye was developed in 2000 by engineers at
Roke Manor Research Limited
Roke Manor Research Limited is a British company based at Roke Manor near Romsey, Hampshire, which conducts research and development in the fields of communications, networks, electronic sensors, artificial intelligence, machine learning, data ...
, then a
Siemens
Siemens AG ( ) is a German multinational conglomerate corporation and the largest industrial manufacturing company in Europe headquartered in Munich with branch offices abroad.
The principal divisions of the corporation are ''Industry'', '' ...
subsidiary in
Romsey, England. Paul Hawkins and David Sherry submitted a United Kingdom patent application for the technology, but this was subsequently withdrawn.
[VIDEO PROCESSOR SYSTEMS FOR BALL TRACKING IN BALL GAMES](_blank)
esp@cenet Patent document, 14 June 2001 All of the technology and intellectual property was spun off into a separated company, Hawk-Eye Innovations Ltd, based in
Winchester, Hampshire
Winchester is a cathedral city in Hampshire, England. The city lies at the heart of the wider City of Winchester, a local government district, at the western end of the South Downs National Park, on the River Itchen. It is south-west of Londo ...
. This was initially established as a joint venture between Roke Manor Research and
Sunset + Vine.
At the time, Sunset + Vine produced the
Channel 4
Channel 4 is a British free-to-air public broadcast television network operated by the state-owned enterprise, state-owned Channel Four Television Corporation. It began its transmission on 2 November 1982 and was established to provide a four ...
television cricket coverage where Hawk-Eye was first used.
On 14 June 2006 a group of investors—led by the
Wisden Group The Wisden Group was a group of companies formed by John Wisden & Co Ltd, publishers of ''Wisden Cricketers' Almanack''. As well as John Wisden & Co, the group included the magazine ''The Wisden Cricketer'', Cricinfo – the world's highest traffic ...
and that included
Mark Getty
Sir Mark Harris Getty, (born 9 July 1960) is an Irish businessman who is the co-founder and chairman of Getty Images.
Life and career
A member of the prominent Getty family, he is the younger son of John Paul Getty Jr. and his first wife, ...
, a member of the wealthy American family and business dynasty—bought the company for £4.4m.
The acquisition was intended to strengthen Wisden's presence in cricket and allow it to enter tennis and other international sports, with Hawk-Eye working on implementing a system for basketball. According to Hawk-Eye's website, the system produces much more data than that shown on television.
Put up for sale in September 2010, it was sold as a complete entity to Japanese electronic giant
Sony
, commonly stylized as SONY, is a Japanese multinational conglomerate corporation headquartered in Minato, Tokyo, Japan. As a major technology company, it operates as one of the world's largest manufacturers of consumer and professional ...
in March 2011 in a deal that valued the company at £15m-£20m.
[Website company]
About Hawk Eye
, visited 25 May 2012
Deployment in sport
Cricket
The technology was first used by
Channel 4
Channel 4 is a British free-to-air public broadcast television network operated by the state-owned enterprise, state-owned Channel Four Television Corporation. It began its transmission on 2 November 1982 and was established to provide a four ...
during a
Test match Test match in some sports refers to a sporting contest between national representative teams and may refer to:
* Test cricket
* Test match (indoor cricket)
* Test match (rugby union)
* Test match (rugby league)
* Test match (association football)
...
between
England
England is a country that is part of the United Kingdom. It shares land borders with Wales to its west and Scotland to its north. The Irish Sea lies northwest and the Celtic Sea to the southwest. It is separated from continental Europe b ...
and
Pakistan
Pakistan ( ur, ), officially the Islamic Republic of Pakistan ( ur, , label=none), is a country in South Asia. It is the world's List of countries and dependencies by population, fifth-most populous country, with a population of almost 24 ...
on
Lord's Cricket Ground, on 21 May 2001. It is used by the majority of television networks to track the trajectory of balls in flight. Its major use in cricket broadcasting is in analysing LBW decisions, where the likely path of the ball can be projected forward, through the
batsman
In cricket, batting is the act or skill of hitting the cricket ball, ball with a cricket bat, bat to score runs (cricket), runs and prevent the dismissal (cricket), loss of one's wicket. Any player who is currently batting is, since Septembe ...
's legs, to see if it would have hit the
stumps.
In the winter season of 2008/2009 the
ICC trialled a referral system where Hawk-Eye was used for referring decisions to the third umpire if a team disagreed with a
leg before wicket
Leg before wicket (lbw) is one of the ways in which a batsman can be dismissed in the sport of cricket. Following an appeal by the fielding side, the umpire may rule a batter out lbw if the ball would have struck the wicket but was instead in ...
(LBW) decision. Initially the third umpire was able to look at what the ball actually did up to the point when it hit the batsman, but could not look at the predicted flight of the ball after it hit the batsman. The third umpire is now able to see the projected path of the ball too, and Hawk-Eye is currently sanctioned in international cricket even though some doubts remain about its accuracy.
When an LBW decision is referred to Hawk-Eye, it assists in assessing against three criteria:
* Where the ball pitched (in particular with respect to the stumps)
* The location of impact on the leg of the batsman (in particular with respect to the stumps)
* The projected path of the ball past the batsman
In all three cases, marginal calls result in the on-field umpire's call being maintained.
Due to its real-time coverage of bowling speed, the system is also used to show delivery patterns of a bowler's behaviour such as
line and length
Line and length in cricket refers to the direction and point of bouncing on the pitch of a delivery. The two concepts are frequently discussed together.
Line
The line of a delivery is the direction of its trajectory measured in the horizontal pl ...
, or
swing/turn information. At the end of an
over
Over may refer to:
Places
*Over, Cambridgeshire, England
*Over, Cheshire, England
*Over, South Gloucestershire, England
* Over, Tewkesbury, near Gloucester, England
** Over Bridge
*Over, Seevetal, Germany
Music
Albums
* ''Over'' (album), by Pe ...
, all six deliveries are often shown simultaneously to illustrate a bowler's variations, such as slower deliveries, bouncers and leg-cutters. A complete record of a bowler can also be shown over the course of a match.
Batsmen also benefit from the analysis of Hawk-Eye, as a record can be brought up of the deliveries from which a batsman scored. These are often shown as a 2-D silhouetted figure of a batsman and colour-coded dots of the balls faced by the batsman. Information such as the exact spot where the ball pitches or speed of the ball from the bowler's hand (to gauge batsman reaction time) can also help in post-match analysis.
Tennis
In
Serena Williams
Serena Jameka Williams (born September 26, 1981) is an American inactive professional tennis player. Considered among the greatest tennis players of all time, she was ranked world No. 1 in singles by the Women's Tennis Association (WTA) for ...
's quarter final loss to
Jennifer Capriati
Jennifer Maria Capriati (born March 29, 1976) is an American former world No. 1 tennis player. A member of the International Tennis Hall of Fame, she won three singles Grand Slam titles and was the gold medalist at the 1992 Summer Olympics ...
at the
2004 US Open, three line calls went against Williams in the final set, and Auto-Ref system was being tested during the match. Though the calls were not reversed, there was one overrule of a clearly correct call by the chair umpire
Mariana Alves that the TV replay showed to be good. These errors prompted talks about line calling assistance especially as the Auto-Ref system was being tested by the U.S. Open at that time and was shown to be very accurate.
In late 2006 Hawk-Eye was tested by the
International Tennis Federation
The International Tennis Federation (ITF) is the governing body of world tennis, wheelchair tennis, and beach tennis. It was founded in 1913 as the International Lawn Tennis Federation by twelve national tennis associations. As of 2016, there a ...
(ITF) in New York City and was passed for professional use. Hawk-Eye reported that the New York tests involved 80 shots being measured by the ITF's high speed camera, a device similar to
MacCAM
MacCAM (often written as MacCam, Mac-Cam or Mac Cam) is a system of slow-motion cameras developed by FastCAM Replay LLC and DEL Imaging Systems LLC used during tennis matches to replay close or controversial line calls. The system is named after ...
. During an early test of the system at an exhibition tennis tournament in Australia (seen on local TV), there was an instance when the tennis ball was shown as "Out", but the accompanying word was "In". This was explained to be an error in the way the tennis ball was shown on the graphical display as a circle, rather than as an ellipse. This was immediately corrected.
Hawk-Eye has been used in television coverage of several major tennis tournaments, including
Wimbledon
Wimbledon most often refers to:
* Wimbledon, London, a district of southwest London
* Wimbledon Championships, the oldest tennis tournament in the world and one of the four Grand Slam championships
Wimbledon may also refer to:
Places London
* ...
, the
Queen's Club Championships
The Queen's Club Championships is an annual tournament for male tennis players, held on grass courts at the Queen's Club in West Kensington, London. The event is part of the ATP Tour 500 series on the Association of Tennis Professionals (ATP) ...
, the Australian Open, the
Davis Cup
The Davis Cup is the premier international team event in men's tennis. It is run by the International Tennis Federation (ITF) and is contested annually between teams from competing countries in a knock-out format. It is described by the organis ...
and the
Tennis Masters Cup
The ATP Finals is the season-ending championship of the ATP Tour. It is the most significant event in the annual ATP calendar after the four majors as it features the top-eight singles players and top-eight doubles teams based on their results th ...
. The
US Open Tennis Championship
The US Open Tennis Championships is a hardcourt tennis tournament held annually in Queens, New York. Since 1987, the US Open has been chronologically the fourth and final Grand Slam tournament of the year. The other three, in chronological ord ...
announced they would make official use of the technology for the
2006 US Open where each player receives two challenges per set. It is also used as part of a larger tennis simulation implemented by
IBM called
PointTracker.
The
2006 Hopman Cup in
Perth, Western Australia
Perth is the capital and largest city of the Australian state of Western Australia. It is the fourth most populous city in Australia and Oceania, with a population of 2.1 million (80% of the state) living in Greater Perth in 2020. Perth is ...
, was the first elite-level tennis tournament where players were allowed to challenge point-ending line calls, which were then reviewed by the referees using Hawk-Eye technology. It used 10 cameras feeding information about ball position to the computers.
Jamea Jackson
Jamea Jackson ( ; born September 7, 1986) is an American former Women's Tennis Association (WTA) player and current United States Tennis Association (USTA) coach. She reached a singles ranking of 45 in the world at the end of 2006.
Jackson was b ...
was the first player to challenge a call using the system.
In March 2006, at the
Nasdaq-100 Open
The Miami Open (also known as the Miami Masters, and currently branded as the Miami Open presented by Itaú for sponsorship reasons) is a tennis tournament held at Hard Rock Stadium in Miami Gardens, Florida. It is part of the men's ATP Tour Mas ...
in
Key Biscayne, Florida
Key Biscayne is an island town in Miami-Dade County, Florida. The population was 12,344 at the 2010 census.
Key Biscayne lies south of Miami Beach and east of Miami. The village is connected to Miami via the Rickenbacker Causeway, originall ...
, Hawk-Eye was used officially for the first time at a tennis tour event. Later that year, the
US Open became the first grand-slam tournament to use the system during play, allowing players to challenge line calls.
The
2007 Australian Open was the next grand-slam event to implement Hawk-Eye in challenges to line calls, where each tennis player in Rod Laver Arena was allowed two incorrect challenges per set and one additional challenge should a tiebreak be played. In the event of an advantage final set, challenges were reset to two for each player every 12 games, i.e. 6 all, 12 all. Controversies followed the event as at times Hawk-Eye produced erroneous output. In 2008, tennis players were allowed three incorrect challenges per set instead. Any leftover challenges did not carry over to the next set. Once,
Amélie Mauresmo
Amélie Simone Mauresmo (; born 5 July 1979) is a French former world No. 1 tennis player and tournament director. Mauresmo won two major singles titles at the 2006 Australian Open and Wimbledon Championships, and also won the silver medal in s ...
challenged a ball that was called in, and Hawk-Eye showed the ball was out by less than a millimetre, but the call was allowed to stand. As a result, the point was replayed and Mauresmo did not lose an incorrect challenge.
The Hawk-Eye technology used in the
2007 Dubai Tennis Championships had some minor controversies. Defending champion Rafael Nadal accused the system of incorrectly declaring an out ball to be in following his exit. The umpire had called a ball out; when
Mikhail Youzhny
Mikhail Mikhailovich Youzhny (born 25 June 1982), nicknamed "Misha" and "Colonel" by his fans, is a Russian retired professional tennis player who was ranked inside the top 10 and was the Russian No. 1. He achieved a top-10 ranking by the Assoc ...
challenged the decision, Hawk-Eye said it was in by . Youzhny said after that he himself thought the mark may have been wide but then offered that this kind of technology error could easily have been made by linesmen and umpires. Nadal could only shrug, saying that had this system been on clay, the mark would have clearly shown Hawk-Eye to be wrong.
The area of the mark left by the ball on hard court is a portion of the total area that the ball was in contact with the court (a certain amount of pressure is required to create the mark).
The
2007 Wimbledon Championships also implemented the Hawk-Eye system as an officiating aid on
Centre Court
Centre Court is a tennis court at the All England Lawn Tennis and Croquet Club (also known as the All England Club) and is the main court used in The Championships at Wimbledon, the third annual Grand Slam event of the tennis calendar. It is co ...
and Court 1, and each tennis player was allowed three incorrect challenges per set. If the set produced a tiebreak, each player was given an additional challenge. Additionally, in the event of a final set (third set in women's or mixed matches, fifth set in men's matches), where there is no tiebreak, each player's number of challenges was reset to three if the game score reached 6–6, and again at 12–12.
Teymuraz Gabashvili
Teymuraz Besikovich Gabashvili ( rus, Теймураз Бесикович Габашвили, , tɛɪ̯mʊˈraz ɡəbɐˈʂvʲilʲɪ; born 23 May 1985) is a Russian professional tennis player. He has a career-high singles ranking of World No. 4 ...
, in his first round match against
Roger Federer
Roger Federer (; born 8 August 1981) is a Swiss former professional tennis player. He was ranked List of ATP number 1 ranked singles tennis players#Weeks at No. 1, world No. 1 by the Association of Tennis Professionals (ATP) for 310 weeks, in ...
, made the first-ever Hawk-Eye challenge on Centre Court. Additionally, during the finals of Federer against
Rafael Nadal
Rafael Nadal Parera (, ; born 3 June 1986) is a Spanish professional tennis player. He is currently ranked world No. 2 in singles by the Association of Tennis Professionals (ATP). He has been ranked List of ATP number 1 ranked singles tennis ...
, Nadal challenged a shot which was called out. Hawk-Eye showed the ball as in, just clipping the line. The reversal agitated Federer enough for him to request (unsuccessfully) that the umpire turn off the Hawk-Eye technology for the remainder of the match.
In the
2009 Australian Open fourth round match between Roger Federer and
Tomáš Berdych
Tomáš Berdych (; born 17 September 1985) is a Czech former professional tennis player. His most notable achievement was reaching the final of the 2010 Wimbledon Championships, causing consecutive upsets by defeating top seed and six-time champi ...
, Berdych challenged an out call. The Hawk-Eye system was not available when he challenged, likely due to a particularly pronounced shadow on the court. As a result, the original call stood.
In the
2009 Indian Wells Masters quarterfinals match between
Ivan Ljubičić
Ivan Ljubičić (; born 19 March 1979) is a Croatian former professional tennis player. He reached a career-high Association of Tennis Professionals (ATP) world No. 3 singles ranking on 1 May 2006. His career highlights include reaching a Grand S ...
and
Andy Murray, Murray challenged an out call. The Hawk-Eye system indicated that the ball landed on the centre of the line despite instant replay images showing that the ball was clearly out. It was later revealed that the Hawk-Eye system had mistakenly picked up the second bounce, which was on the line, instead of the first bounce of the ball. Immediately after the match, Murray apologised to Ljubicic for the call, and acknowledged that the point was out.
The Hawk-Eye system was developed as a replay system, originally for TV broadcast coverage. As such, it initially could not call ins and outs live.
The Hawk-Eye Innovations website states that the system performs with an average error of . The standard diameter of a tennis ball is , equating to a 5% error relative to ball diameter. This is roughly equivalent to the fluff on the ball.
Hawk-Eye has developed a technology called 'Hawk-Eye Live', which uses the 10 cameras to call shots in or out in real time, with an 'out' call being signified by a speaker emitting an 'out' sound that emulates a human line judge. The technology was initially expected to be in place for the 2019 US Open. The
2021 Australian Open was the first Grand Slam tournament to use Hawk-Eye Live for all matches in place of line judges, in part to reduce personnel during the
COVID-19 pandemic
The COVID-19 pandemic, also known as the coronavirus pandemic, is an ongoing global pandemic of coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The novel virus was first identif ...
, followed by the US Open later that year. Previously, the 2020 US Open used Hawk-Eye in place of line judges for all matches except those in the two main stadiums.
Clay court tournaments, notably the
French Open
The French Open (french: Internationaux de France de tennis), also known as Roland-Garros (), is a major tennis tournament held over two weeks at the Stade Roland Garros in Paris, France, beginning in late May each year. The tournament and ven ...
, are generally free of Hawk-Eye technology due to marks left on the clay where the ball bounced to evidence a disputed line call. Chair umpires are then required to get out of their seat and examine the mark on court with the player by their side to discuss the chair umpire's decision. The
2021 Mutua Madrid Open
The 2021 Madrid Open (sponsored by Mutua) was a professional tennis tournament played on outdoor clay courts at the Park Manzanares in Madrid, Spain from 29 April – 9 May 2021. It was the 19th edition of the event on the ATP Tour and 12th o ...
became the first major tournament on clay to use an electronic system to check the bounce of the ball on the court when in doubt. The system was developed by
FoxTenn, a Spanish company located in
Barcelona
Barcelona ( , , ) is a city on the coast of northeastern Spain. It is the capital and largest city of the autonomous community of Catalonia, as well as the second most populous municipality of Spain. With a population of 1.6 million within ci ...
. It uses real images of the ball captured by 40 cameras located at ground level, synchronized with lasers and working at up to 3,000 images per second to determine whether it has bounced in or out of regulatory limits. This system was previously used at the
2020 Rio Open
The 2020 Rio Open presented by Claro was a professional men's tennis tournament played on outdoor clay courts. It was the seventh edition of the Rio Open, and part of the ATP Tour 500 series on the 2020 ATP Tour. It took place in Rio de Janeiro ...
in
Rio de Janeiro
Rio de Janeiro ( , , ; literally 'River of January'), or simply Rio, is the capital of the state of the same name, Brazil's third-most populous state, and the second-most populous city in Brazil, after São Paulo. Listed by the GaWC as a b ...
and at the
2021 MUSC Health Women's Open in
Charleston, South Carolina
Charleston is the largest city in the U.S. state of South Carolina, the county seat of Charleston County, and the principal city in the Charleston–North Charleston metropolitan area. The city lies just south of the geographical midpoint o ...
.
Unification of rules
Until March 2008, the International Tennis Federation (ITF),
Association of Tennis Professionals
The Association of Tennis Professionals (ATP) is the governing body of the men's professional tennis circuits – the ATP Tour, the ATP Challenger Tour and the ATP Champions Tour. It was formed in September 1972 by Donald Dell, Jack Kramer, an ...
(ATP),
Women's Tennis Association
The Women's Tennis Association (WTA) is the principal organizing body of women's professional tennis. It governs the WTA Tour which is the worldwide professional tennis tour for women and was founded to create a better future for women's tenni ...
(WTA),
Grand Slam
Grand Slam most often refers to:
* Grand Slam (tennis), one player or pair winning all four major annual tournaments, or the tournaments themselves
Grand Slam or Grand slam may also refer to:
Games and sports
* Grand slam, winning category te ...
Committee, and several individual tournaments had conflicting rules on how Hawk-Eye was to be utilised. A key example of this was the number of challenges a player was permitted per set, which varied among events.
Some tournaments allowed players a greater margin for error, with players allowed an unlimited numbers of challenges over the course of a match.
In other tournaments players received two or three per set.
On 19 March 2008, the aforementioned organizing bodies announced a uniform system of rules: three unsuccessful challenges per set, with an additional challenge if the set reaches a tiebreak. In an advantage set (a set with no tiebreak) players are allowed three unsuccessful challenges every 12 games. The next scheduled event on the men and women's tour, the
2008 Sony Ericsson Open, was the first event to implement these new, standardized rules.
Association football
Hawk-Eye is one of the
goal-line technology In many outdoor ball sports, a goal line is a line in front of goal post and which a team attempts to advance the ball or puck towards to score a goal or points. In particular, see:
* Football pitch
A football pitch (also known as soccer fiel ...
(GLT) systems authorised by
FIFA
FIFA (; stands for ''Fédération Internationale de Football Association'' ( French), meaning International Association Football Federation ) is the international governing body of association football, beach football and futsal. It was found ...
. Hawk-Eye tracks the ball, and informs the
referee if a ball fully crosses the goal line into the
goal
A goal is an idea of the future or desired result that a person or a group of people envision, plan and commit to achieve. People endeavour to reach goals within a finite time by setting deadlines.
A goal is roughly similar to a purpose or ai ...
. The purpose of the system is to eliminate errors in assessing if a
goal
A goal is an idea of the future or desired result that a person or a group of people envision, plan and commit to achieve. People endeavour to reach goals within a finite time by setting deadlines.
A goal is roughly similar to a purpose or ai ...
was scored. The Hawk-Eye system was one of the systems trialled by the sport's governors prior to the 2012 change to the
Laws of the Game that made GLT a permanent part of the game,
and it has been used in various competitions since then. GLT is not compulsory and, owing to the cost of Hawk-Eye and its competitors, systems are only deployed in a few high-level competitions.
, licensed Hawk-Eye systems were installed at 96 stadiums. By number of installations, Hawk-Eye is the most popular GLT system. Hawk-Eye is the system used in the
Premier League
The Premier League (legal name: The Football Association Premier League Limited) is the highest level of the men's English football league system. Contested by 20 clubs, it operates on a system of promotion and relegation with the English Foo ...
,
Serie A
The Serie A (), also called Serie A TIM for national sponsorship with TIM, is a professional league competition for football clubs located at the top of the Italian football league system and the winner is awarded the Scudetto and the Coppa ...
and
Bundesliga
The Bundesliga (; ), sometimes referred to as the Fußball-Bundesliga () or 1. Bundesliga (), is a professional association football league in Germany. At the top of the German football league system, the Bundesliga is Germany's primary footba ...
among other leagues.
Snooker
At the
2007 World Snooker Championship, the
BBC #REDIRECT BBC #REDIRECT BBC
Here i going to introduce about the best teacher of my life b BALAJI sir. He is the precious gift that I got befor 2yrs . How has helped and thought all the concept and made my success in the 10th board exam. ...
...
used Hawk-Eye for the first time in its television coverage to show player views, particularly of potential snookers. It has also been used to demonstrate intended shots by players when the actual shot has gone awry. It is now used by the BBC at every World Championship, as well as some other major tournaments. The BBC used to use the system sporadically, for instance in the 2009 Masters at Wembley the Hawk-Eye was at most used once or twice per frame. Its usage has decreased significantly and is now only used within the World Championships and very rarely in any other tournament on the snooker tour. In contrast to tennis, Hawk-Eye is never used in snooker to assist referees' decisions and primarily used to assist viewers in showing what the player is facing.
in 2013. This followed consideration by the
. A trial took place at Croke Park on 2 April 2011. The double-header featured football between
. Over the previous two seasons there had been many calls for the technology to be adopted, especially from Kildare fans, who saw two high-profile decisions go against their team in important games. The GAA said it would review the issue after the 2013
was presented.
Hawk-Eye's use was intended to eliminate contentious scores. Its first use in the championship came on Saturday 1 June 2013 for the
. Hawk-Eye determined that Offaly substitute
's attempted point had gone wide 10 minutes into the second half.
Use of Hawk-Eye was suspended during the
semi-finals on 18 August due to a human error during a minor (under-18) hurling game between Limerick and Galway.
During the minor game, Hawk-Eye ruled a point for Limerick as a miss although the graphic showed the ball passing inside the posts, causing confusion around the stadium – the referee ultimately waved the valid point wide provoking anger from fans, viewers and TV analysts covering the game live. The system was subsequently stood down for the senior game which followed, owing to "an inconsistency in the generation of a graphic". Limerick, who were narrowly defeated after extra-time, announced they would be appealing over Hawk-Eye's costly failure.
Hawk-Eye apologised for this incident and admitted that it was a result of human error. The incident drew attention from the UK, where Hawk-Eye had made its debut in English football's
the day before.
, Thurles, in 2016. There is no TV screen at Semple: instead, an electronic screen displays a green ''Tá'' if a score has been made, and a red ''Níl'' if the shot is wide. It was used at a third venue,
.
Hawk-Eye was at the centre of several contentious decisions during the first half of the first
.
, the referee being forced to alter the score and, later, Hawk-Eye's suspension for the second All-Ireland SFC semi-final between Dublin and
. The GAA confirmed on 15 July that Hawk-Eye would return for the
, following comprehensive testing and a full review of the score detection technology.
No official
term exists, although some publications have used the direct translation ''Súil an tSeabhaic''.
On 4 July 2013, the Australian Football League announced that they would be testing Hawk Eye technology to be used in the Score Review process. Hawk Eye was used for all matches played at the MCG during Round 15 of the 2013 AFL Season. The AFL also announced that Hawk Eye was only being tested, and would not be used in any Score Reviews during the round.
BWF introduced Hawk-Eye technology in 2014 after testing other instant review technologies for line call decision in BWF major events. Hawk-Eye's tracking cameras are also used to provide shuttlecock speed and other insight in badminton matches. Hawk-Eye was formally introduced in
tournament.
Hawk-Eye is now familiar to sport fans around the world for the views it brings into sports like cricket and tennis. Although this new technology has for the most part been embraced, it has received criticism from some quarters. In the
a shot that appeared to be out, was called by Hawk-Eye as in by 1mm, a distance smaller than the advertised mean error of . Some commentators have criticised the system's statistical margin of error as too large. Others have noted that while is extraordinarily accurate, this margin of error is only for the witnessed trajectory of the ball. In 2008, an article in a peer-reviewed journal consolidated many of these doubts. The authors acknowledged the value of the system, but noted that it was probably fallible to some extent, and that its failure to depict a margin of error gave a spurious depiction of events. The authors also argued that the probable limits to its accuracy were not acknowledged by players, officials, commentators or spectators. They hypothesised that Hawk-Eye may struggle with predicting the trajectory of a cricket ball after bouncing: the time between a ball bouncing and striking the batsman may be too short to generate the three frames (at least) needed to plot a curve accurately.
. A similar version of the system has since been incorporated into the
version of the game, although it does feature a normal challenge of the ball which does not use the Hawk-Eye feature. It is also featured (Called Big Eye) in
.
is a computer system which has been used on the ATP and WTA professional tennis tours as an electronic line judge since 1980, now superseded by Hawk-Eye at Grand Slam tournaments.
which uses real data to trace back ball path and marking, including on clay surfaces.