This one is new to me. The Picasso Summer is a 1969 feature based on a Ray Bradbury short story. It includes an impressively lengthy animated sequence based on Picasso’s artwork that holds up on its own.
The animation is credited to Wes Herschensohn, who was a producer on the film and also an animation veteran. But this in-depth article about the film claims the animation was produced by John and Faith Hubley. Based on the style, it’s entirely plausible that the Hubleys provided the animation, though I’ve never heard of them being associated with the project. Whoever made this, it’s a unique interpretation of Picasso’s artwork into animation, and deserves more attention than it has received.