A good deal livelier than the usual music-doc embalming, this worshipful tribute to jazz singer Anita O’Day—completed shortly before her death in 2006 by her then manager, Robbie Cavolina, and co-director Ian McCrudden—is rescued from its own adoration (and too-busy faux-’50s graphics) by its subject: a tough cookie, racetrack devotee, and brassy raconteur who may be the least self-pitying reformed addict in the history of pop biographies. Whether in film clips dating back to her 1940s emergence in Gene Krupa’s big band, or in interviews taken near the end of her life, the mercurial O’Day remains a voracious, vivacious presence who resists being filed away, even as the directors marshal hall-of-fame testimony from her many admirers—from Margaret Whiting and Dr. Billy Taylor to actor-director John Cameron Mitchell, who compares her spontaneity to Cassavetes. As opposed to her scandalous autobiography High Times Hard Times, the movie is downright reticent on subjects such as a backstage rape and subsequent abortion. The directors prefer to secure O’Day’s due as, in the words of critic Will Friedwald, the only white jazz singer who belongs in the company of Ella Fitzgerald and Billie Holiday. To watch her landmark tea-dress slink through “Sweet Georgia Brown” at the 1958 Newport Jazz Festival is to hear every syllable expressed as if at the spark of conception, fully formed and felt.