Universal Pictures is giving “Jem and the Holograms” fans a chance to appear — briefly — in the upcoming teen-musical fantasy, with winners selected based on “Jem”-inspired videos posted on social channels.

But the on-screen fan appearances will be limited to short excerpts from their video creations, according to the studio; producers have yet to determine how many user-submitted clips they may include in the final cut. That’s a far cry from what the project’s filmmakers said in March 2014, when they told fans they were actually seeking to discover unknown talent online to cast as stars in the movie.

“This is the real way we’re making this movie — this is not a contest,” director Jon M. Chu said in a YouTube video announcing the movie. Added producer Scooter Braun, “We want you to be our movie star.” That idea, however, fell by the wayside.

Universal launched the digital casting call, such as is it, at VidCon, the annual digital-video confab taking place this week in Anaheim, Calif., angling to attract YouTube stars to the contest. “Jem and the Holograms,” based on the ’80s animated TV series and Hasbro toy line, is about a small-town girl who becomes a singing superstar.

The hope at this point: to produce a groundswell of user-generated content about “Jem” ahead of the movie’s Oct. 23 premiere, as effectively free publicity.

Universal’s “Star in Jem” contest is inviting anyone to post multiple videos of themselves singing or dancing to one of the songs from the movie (after downloading music from the site). For actors, the studio is looking for testimonials addressed to the fictional Jem about “how she has given you courage to be yourself.” Deadline for submissions is Aug. 10.

Universal also is partnering with Defy Media’s Clevver entertainment digital network on a video campaign promoting the film. That will comprise interviews with top YouTube talent at VidCon about how they rose from obscurity to Internet stardom (i.e., just like Jem).

In addition, Universal is sponsoring “The Prom” at VidCon on Saturday night. The event will include “Jem and the Holograms” giveaways, a makeup artist, photo booth and branded beach balls and will feature a music video from the pic.

“Jem and the Holograms” stars Aubrey Peeples (ABC’s “Nashville”) in the title role. Cast also includes Stefanie Scott, Aurora Perrineau, Hayley Kiyoko, Ryan Guzman, Molly Ringwald and Juliette Lewis.

The movie is directed by Chu (“Justin Bieber: Never Say Never,” “G.I. Joe: Retaliation”) and scripted by Ryan Landels. Producers are Chu, Jason Blum for Blumhouse Prods., Braun for SB Projects, Bennett Schneir, and Brian Goldner and Stephen Davis of Hasbro Studios.