Once upon a time, animated characters were performed by pros whose faces auds didn’t know or see. Today, movie stars and celebrities increasingly fill the roles, both in America and when dubbed abroad. Such casting choices may help with marketing (it helps to have Mike Myers or his French-language counterpart at the press junket), but that doesn’t make the job any easier.To help draw attention to the art of animation acting, Annecy will host a v.o. demo, in which amateurs can try dubbing a French episode of “The Simpsons,” as well as a full-blown contest, with the winners earning special training and a chance to lend their voices to a real cartoon. In the U.S., actors often spread recording sessions over several years. But foreign v.o. artists don’t enjoy that luxury, says Boualem Lamhene, character voice creative director for Disney France. Online piracy has forced U.S. distribs to rush overseas release dates, forcing Boualem’s team to work much faster. Unlike the original cast, whose performances guide the animation, foreign dubbers must match the image while also trying to reflect the American actor’s interpretation of that character.