Vince Guaraldi, the Grammy-winning jazz pianist who accidentally found fame via his music for the animated “Peanuts” TV specials, is the subject of a new documentary making the rounds on the festival circuit.

“The Anatomy of Vince Guaraldi” has won best-doc honors at fests in Colorado and Utah and will be screened at the Temecula Film Festival in September. Its Aug. 1 premiere in Los Angeles doubled as a benefit for the Jazz Bakery, a longtime L.A. jazz haunt that’s searching for a new location.

Writer-director Andrew Thomas, who’s worked on A&E’s “Biography” and History Channel’s “Modern Marvels” documentary series, is a self-described “cultural anthropologist” who’s created a somewhat unconventional take on Guaraldi, who died at age 47 in 1976.

“To really understand who he is,” Thomas says, “you’ve got to take a more existential approach, looking at the environment in which he lived and worked, and the people with whom he associated.” So musicians like Jon Hendricks, Dave Brubeck and George Winston, and comedians including Dick Gregory and Paul Mazursky (who recall working with Guaraldi at San Francisco’s legendary hungry i nightclub) talk not just about the composer but about the atmosphere and social issues of the 1950s and ’60s.

Thomas was friends with Toby Gleason, son of Rolling Stone founding editor Ralph Gleason, having worked on the DVD releases of the elder Gleason’s 1960s series “Jazz Casual.” The discovery of a 16mm print of the original Guaraldi film launched Thomas and Toby on a crusade to interview as many of the musician’s surviving friends and supporters as possible. About 25 minutes of the original are featured in the new film, Thomas says.

Producer Lee Mendelson’s then-radical decision to use a jazz-piano score for his “Peanuts” specials, including the ever-popular “A Charlie Brown Christmas,” were “pure serendipity,” Thomas notes. “That’s worthy of celebration, because it says that the cosmos works. It’s a Zen message, which is so true to the Beat sensibility of Vince’s time.”