1st & Ten (graphics system)

1st & Ten is a computer system that generates and displays one version of the yellow first down line that a TV viewer sees during a live broadcast of a college or professional American football or Canadian football game A competing system that performs the same task using different technology is called L-VIS for Live Video Insertion System. The line, which is not physically present on the field and is seen only by the television audience, spans the width of the football field and indicates the location of the first down marker. The purpose of the line is to make it easier for television viewers to follow play on the field. Some television football broadcasts change the color of the line from yellow to red on 4th down, or show a second computer-generated line (usually blue in color) that marks the line of scrimmage. Other lines are also projected to show other types of field position, including markings for the red zone and the optimum maximum distance for a placekicker's statistical field goal range.

In extreme situations, such as snowstorm or blizzard conditions, an entire virtual field with yard and boundary markers can be projected onto the field in order to allow league officials, broadcasters and viewers some way to follow action when all field markings are obscured by snow, fog or mud.

The system makes use of a combination of motion sensors mounted on the broadcast cameras to record what they are viewing, and/or the use of match moving computer graphics technology and an enhanced version of chroma key or "green screen" technology.

The idea of creating an on-field marker to help TV viewers identify 1st down distances was conceived and patented in 1978 by David W. Crain, who presented the concept to Roone Arledge and Roger Goodman of ABC News and Sports and to the CBS Technology Center. At the time, both decided the broadcast industry was not ready to use Crain's invention.

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