There’s no question that movies wouldn’t be half as effective if it weren’t for their scores. After all, what’s a romance without a swelling orchestra to accompany it? No one knows this better than Lucio Gregoretti, the current composer-in-residence at the Jacob Burns Film Center. He’s written chamber pieces, operas, and other works for the stage, but he’s also written the scores for many Italian films. Gregoretti will give a multimedia performance, titled “From Stravinsky to Sophia Loren: The Musical World of Lucio Gregoretti,” for Copland House at Merestead on March 3. There, he’ll be premiering a new, original work, in addition to performing songs by a host of other composers who’ve influenced him, from Igor Stravinsky to Ennio Morricone.