This year has been a boon for multimedia entertainment, especially in the development of new interactive compact discs featuring live-action talent.In the last quarter alone, three titles have wrapped using actors, and that number is expected to increase dramatically in the coming year. Outer limits Currently, interactive compact discs are limited to images taking up at most half of the television screen. The reason for this is that the video images stored on the compact disc aren’t yet being played back with enough speed or power to appear as 30 frames-per-second. Hardware manufacturers, from Philips Electronics to Sega of America, are all working to upgrade that in 1993. And according to software developers like San Mateo’s Electronic Arts Inc. and L.A.’s Activision Inc., breakthroughs in technology will permit sharper images to be displayed on a full-television screen. Right now, though, there are some limitations. In the case of Electronic Arts’ “Noctropolis,” director Christopher Erhardt shot actors against a totally blue-screened set with a camera in a fixed position. The rest of the scene is taken up by one of 94 hand-painted backgrounds that are scanned into a computer. The two images are later composited. For a joint Propaganda Films/Philips Interactive Media of America title, producer David Reardon also stuck to a blue-screen set. “Voyeur” takes place in a mansion where a politician, played by Robert Culp, is wrestling with the decision to run for president. Budgetary burden Also at odds with filmmaking is the fact that 70% of the $ 670,000 budget is going to be spent in post-production. While Propaganda’s Jonathan Wiedemann arranged for the shoot to be done through the Screen Actors Guild, Electronic Arts decided to forgo Hollywood for the moment. “We don’t fit in yet,” said director Erhardt. “We expect to hear from the unions next year.” That’s likely, according to the head of SAG’s industrial department, Michael Prohaska, since an estimated 200 performers worked on CDs this year.