HAWK EYE TECHNOLOGY IN SPORTS BROADCASTING

Hawk-Eye  is a complex computer system used in cricket, tennis and other sports to visually track the trajectory of the ball and display a record of its most statistically likely path as a moving image. It was developed by engineers at Roke Manor Research Limited of Romsey, Hampshire in the UK, in 2001.

Method of operation

All Hawk-Eye systems are based on the principles of triangulation using the visual images and timing data provided by at least four high-speed video cameras located at different locations and angles around the area of play.^[2] 

 The system rapidly processes the video feeds by a high-speed video camera 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 3D 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 singles, 2s, 3s, 4s and 6s that make up quick-fire 50s or vital centuries are represented by the different colours of the Wagon Wheel, which shows the areas of the field that the batsman has been targeting. Hawk-Eye now has the ability to display wagon wheels over photo realistic or virtual realistic backgrounds, giving broadcasters even more scope to taylor the Hawk-Eye 'look' towards the style of their production.

Hawk-Eye DeSpin Graphics demonstrate how far a delivery has deviated after pitching. Whilst the blue trajectory below represents a ball that does not spin or seam, the red ‘actual delivery’ shows just how much turn the spinner has achieved.

The pure tracking system is combined with a backend 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.

Cricket

It is in cricket TV broadcasts that Hawk-Eye first made its name. The technology is used by broadcasters to resolve LBW shouts and, as with its tennis counterpart, to generate easily-digestible statistics to enhance the viewing experience. Viewers now expect Hawk-Eye to show whether a batsman should have been given ‘in’ or ‘out’: the technology predicts the path of the ball as it comes out of the bounce, thus determining whether the ball would have hit the stumps.

Whilst it is not used officially by the ICC, Hawk-Eye’s six years of technical experience have made it a firm favorite with fans and players of the gam

LBWs

 
Viewers now expect Hawk-Eye’s verdict on lbw ‘shouts’; a testimony to Hawk-Eye’s reputation for accuracy and reliability. The company’s experienced operators will deliver the relevant trajectory, half-mixed with the equivalent video sequence, in time for the first replay. This gives commentators and viewers adequate time to discuss and digest the result before the next ball has been bowled.

Hawk-Eye helps to resolve the following three issues:

• Would the ball have hit the stumps?
• Did the ball pitch in-line?
• Did the ball hit the batsman in-line?

Beehives

Beehives show where the ball has passed the batsman.As with the Pitch Map, the coloured balls correspond to the number of runs that the batsman has achieved from that delivery. Hawk-Eye Beehives can now be shown against a photo realistic or virtual realistic world, as with the Wagon Wheel feature.

RailCam

 The ‘RailCam’ (side view) shot of the VR World can be used to represent differences in speed, bounce and delivery. The trajectories are animated, whilst the speeds provide further evidence of a bowler’s variation or a telling comparison between athletes.

Ball Speeds

Hawk-Eye now has the ability to supply ball speeds as reliably as a radar gun, as demonstrated during the ICC World Twenty20 in South Africa