And you thought you knew the game…

Posted on May 24, 2010 in Sports

Tanaya Singh:

This page is dedicated to all die-hard cricket fans. By “die-hard” I mean the ones who worship Sachin and were found throwing parties when he made the recent historical record, and the ones who stand in front of showroom windows when they don’t want to miss a single ball of the match, and also the ones who sit down full spirited after every game to watch the replays as if they are seeing it for the first time. Yeah, I know that just now, I was successful in talking about half the population of our country. So now that you are a fan, or you think you are one, don’t you think you should have sufficient knowledge not only about the scores and records, but also about the technology used in cricket that helps you see a perfectly ordered match on T.V? Here are a few things you might find new and interesting…

Every time the opposing team claims a LBW against India, you sit in front of the screen with your jaw dropped wide, hoping against hope. Right?! You can shut your jaw now, because there is a technology that helps the umpire in deciding his verdict in case of a doubt. It is called “Hot Spot”. Hot Spot is a system that determines whether the ball has hit the batsman’s bat or the pad. This technique employs two infrared cameras placed on either side of the ground. The work of the cameras is to sense and measure the friction generated due to heat when the ball hits the pad, the bat, the ground or the glove. Using a subtraction method, the camera generates a series of black and white negative images on a computer screen. This leads to the localising of the point of contact of the ball which is shown with discerning clarity on the screen. It also helps the audience in seeing the part of the bat that was hit by the ball. While a ball not hitting the middle portion of the bat tends to get deviated from the required path, a ball hitting the top edge goes flying in the air and if the lower edge comes into contact, the ball hits hard into the ground. So we get valuable information while analyzing the strokes. This mechanism was introduced in 2006 by channel 9 (the famous worldwide T.V. network of Australia) after the use of stump cameras and snickometer. Hot spot had a lot of advantages over the competing technology “snickometer”.

Commonly known as the snick, this device is a T.V. tool used to track the path of the ball by picking up and analysing the sounds from the pitch and stump microphones. This is used in slow motion television replays by commentators to determine the path of the ball. They listen and view the recorded waveform. From that, viewers can tell whether the ball hit a pad (a flat, dull display) or hit the bat (a lot sharper graphic) or just went pass (a flat line). However, it sometimes produces inconclusive and equivocal results and hence the hot spot dominates the snick for most of the T.V. channels today.

Next in row we have the “Hawk Eye”. Fans all over the world these days want to be involved in each and every aspect of the game. Hawk eye is one of the most energising things that happened to the players, fans and television viewers recently. It is a computer system used to track the path of the ball and display and record the most statistically accurate and perspicacious path as a moving image. This was first used in 2001 by channel 4 during a test match between England and Pakistan. Since then it has been used by a majority of television channels to determine the trajectory of the ball during its flight. The basic use of this method is in taking leg before wicket decisions wherein the path of the ball can be extended forward in between the batsman’s leg to see whether it would have hit the wicket or not. All hawk eye systems use the triangulation principle which utilises at least four cameras installed at varied positions on the field. It processes the video feeds with the help of high speed video processor and ball tracker. The data base of the system contains predefined models of the playing area and the game rules. In each frame sent from each camera, the system identifies the group of pixels corresponding 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. Then a graphic image of the ball path is generated. With this we get the real-time coverage of the bowling speed. We also see the complete analysis of the bowling style of a particular bowler at the end of six balls, such as delivery variations, bouncers and slow deliveries. The invention of this system has helped a lot in post match analysis by teams and coaches. Other than cricket, hawk eye is being used in tennis, snooker, and a lot of computer games as well.

So the next time you are watching your favourite sport, you would not just be looking at those coloured dots, you’ll know where they come from. Enjoy the game.

The writer is a correspondent of Youth Ki Awaaz.