Football Tech Magic

With the beginning of the football season, millions of fans will tune in to watch their favorite teams. Computer-generated graphics and multiple camera angles have improved the experience for television audiences. Two of the most popular: the yellow first-down line and three-dimensional replays.

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1st & 10

The yellow first-down line that appears on the television screen is computer-generated. A special mount on a television camera encodes its movements, including tilt, pan, zoom and focus.

This information is sent to a central computer, which determines the camera’s relation to the field using a 3-D model.

The system then notes which pixels in the frame make up the location of the real first-down line. After determining which camera is on, a computer draws the yellow first-down line in video 60 times per second. It takes eight computers working together to produce the yellow line.

Color palettes prevent the first-down line from obstructing moving objects on the field, such as players. One palette contains colors for the playing field; the other contains colors for the players, referees and ball. Before drawing the first-down line, the computer notes which pixels it should cover and which it shouldn’t.

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EyeVision

Multiple camera shots provide a 270-degree view of the field.

About 30 live cameras are installed along the periphery of the stadium. One “master” camera, controlled by a human operator, follows the game action. The other cameras are synchronized to follow the “master” as it moves so they all face the same location. The image captured by each camera is played in sequence to achieve a rotational effect.

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Sources: How Stuff Works, Sportvision, Core Digital Technologies

Researched by CHRISTINE FREY/Los Angeles Times