“We knew quickly that we were going to have to look at crowd and audio in a different way. The only thing we didn’t know was the date when we were going to have to be ready to go,” Zager said.

It is definitely an improvement over the virtual crowds Spain’s top soccer league used. The fans on those broadcasts appeared as if they were imposed on a blank background. The Fox version features fans who appear lifelike and three-dimensional.

Fox worked on the project with Silver Spoon, a real-time animation and virtual production studio. Silver Spoon scanned in all the ballparks and fans so their motions sitting and standing could be properly rendered.

The fans can do up to 500 actions, ranging from high fives during a home run to doing the wave. The system can control the percentage of fans in the stadium during a game as well as who they are cheering for.

For example, Saturday’s Brewers-Cubs game could create a crowd that is 75% Cubs and 25% Brewers. It can also make it appear as if most of them have left if it is a 9-1 ballgame in the ninth inning.

The system will be able to adapt to the weather. When the temperature gets colder in the fall, winter jackets and hats can be added to the fans.

Major League Soccer is using virtual ads and scoreboards to show fans during its MLS is Back tournament in Florida, but only one camera is able to show that. Fox will have four of its 10 cameras that it will use for baseball games calibrated to show the virtual crowds. Zager said more may be calibrated as the season goes along.