Officials were initially hopeful that the system could be used at this year's World Cup. But after tests late last year in a Peruvian tournament, FIFA announced that the system was not yet ready for top tournament use. Neither the companies nor FIFA provided details on exactly what the problems were.
"From the technological side, there are still some things that needed to be cleared up," Anne Putz, a spokeswoman for Adidas in Germany, said this week.
Cumming, however, said the system had several problems. Balls that were shot over the goal, but landed on the net, were counted as goals. Shot information could take several seconds to reach referees. And perhaps worst of all, the presence of several balls on the field simultaneously--as when a ball boy threw an extra ball on the field slightly early--could crash the system, the former top ref said.
A spokesman for Cairos Technologies said further tests would be scheduled after the close of the World Cup.
Can the camera be fooled?
A rival Italian technology that would use "high-performance digital cameras" is also in the early experimental stages. FIFA officials gave their go-ahead last March but have not yet provided any details on the technology, and have not yet scheduled any official tests.
Details are scarce on precisely what the Italian system would entail. But the Italian football association has been funding research into such a system for several years, and published papers outline some of the difficulties.
An automatic camera-based system that doesn't rely on a separate observer off-field has several difficulties, researchers have written. Genuine image recognition is perhaps the trickiest part--any system must be able to distinguish a ball crossing the goal line from a hand, foot or stray pigeon, for example.
These and other hurdles mean that, as the teams winnow down to just two next month, the referees and their assistants will still be relying only on the evidence of their own, fallible senses. But until a team loses a game because of a bad call, don't expect to hear many complaints from soccer die-hards.
"You have to look at soccer as being a human game," Cumming said. "It's the greatest game, the people's game. And people make mistakes. If you sanitize football too much, you lose the beauty of the game."
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