Back when rock 'n' roll was still a new adventure, Janis Joplin proved it wasn't just for the boys.
The big-voiced, bluesy singer dominated the stage, forged her own path and paved the way for female singers to come.
But 45 years after her death from a drug overdose in 1970, music is still "a very male-dominated industry", said Amy Berg, director of the new documentary Janis: Little Girl Blue.
Berg's film includes on-screen interviews with Joplin's ex-bandmates and other 1960s musicians - almost all of them male. She says several female performers of the era turned her down, including former Jefferson Airplane singer Grace Slick.
"Grace Slick did not think that people wanted to see her how she looks today, because she was such a beautiful pop star in her 20s," Berg said at the Venice Film Festival, where Janis had its world premiere this week. "That's kind of tragic, I think. I really wanted to get that female perspective."