4553 covers of Time magazine, 1923-2008.
The x axis is time, the y axis is a composite dimension of brightness, hue, and saturation measures that were automatically extracted from the images.
The graph shows the complicated transition from black and white to color printing and indicates some basic design trends in various eras of the publication.
Image processing: NERSC. Visualization: Software Studies Initiative, Calit2 + UCSD.