How is the cricket ball traced during a match?so as to get the virtual view to see lbw decision and others ?

Question

as we have all seen the path of the cricket ball is drawn exactly in the way if was bowled. how this is done ? are there any special cameras for this? then where are these cameras placed ??

Answer 1

Hawkeye is a computer-generated system where data from six different cameras in completely different locations are superimposed to give a more-or-less exact description of the trajectory of the ball.

Answer 2

HAwk-Eye uses six video cameras (or at least 4 cams ) which uses  a special image-processing system from Roke Manor Research (a Siemens R&D company) and commercial off-the-shelf hardware along with six specially placed cameras. Hawk Eye incorporates both image analysis and radar technology. The six fixed JAI monochrome cameras, with a 120 MHz frame rate, are placed around the playing field ( http://www.pcquest.com/images/HAWKEYE1_m... ). They track the ball's entire trajectory, right from the point where it is released from the bowler's hand to the point the ball is considered dead. This is updated 100 times every second. The cameras are used in two sets, and a multi-channel frame grabber handles each set. The images captured are then processed by software to produce a 3-D image. The future path is predicted using a parametric model. The system is able to locate the ball in 3-D and can predict the motion with a claimed accuracy of 5 mm.

Answer 3

Hawk-Eye is a computer system used in cricket, tennis and other sports to visually track the path of the ball and display a record of its actual path as graphic image. In some sports, like tennis, it is now part of the adjudication process. It is also able to predict the future path of a ball. It was developed by engineers at Roke Manor Research Limited of Romsey, Hampshire in the UK, in 2001. The patent is held by Dr Paul Hawkins and David Sherry. Later, the technology was spun off into a separate company, Hawk-Eye Innovations Ltd., as a joint venture with television production company Sunset + Vine.

Cricket

The technology was first used by Channel 4 during a Test match between England and Pakistan on Lord's Cricket Ground, on 21 May 2001. However, the system is not used by the umpires to adjudicate on LBW decisions in Test cricket or One Day International cricket. It is used primarily by the majority of television networks to track the trajectory of balls in flight.

Its major use in cricket is in analysing leg before wicket decisions, where the likely path of the ball can be projected forward, through the batsman's legs, to see if it would have hit the wicket. Currently this information is only visible to television viewers, although it may be adopted in the future by the third umpire, who currently sees only conventional slow motion replays and can only adjudicate on line decisions (run outs or stumpings) or situations where the on-field umpire's view is impeded. Consultation of the third umpire, for conventional slow motion or hawkeye, on leg before wicket decisions is not currently sanctioned in international cricket and doubts remain about its accuracy in cricket.

Due to its realtime coverage of bowling speed, the systems are also used to show delivery patterns of bowler's behaviour such as line and length, or swing/turn information. At the end of an over, all six deliveries are often shown simultaneously to show 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 batsmen scored from. These are often shown as a 2-D silhouetted figure of a batter and colour-coded dots of the balls faced by the batsman or a "wagon wheel" (an aerial view of the batsman's shots all round the ground). 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.

International cricket Council(ICC) has now started using hawk-eye technology to assist the decisions made by the umpire.However this is still on a trial status.This was first introduced in the Test series between India and sri lanka (july/August 2008).ICC is trialing a new "reviewing system" where it makes possible for the players to challenge the decision of umpire.Television umpires can get the assistance of hawk-eye when it comes to LBW decisions.

Answer 4

There are cameras all around the stadium in Cricket and Tennis (about 20 all up) that film every ball and there are a mass of computers that judge height and direction to accurately display the balls estimated travel.