This version uses four photos and a simple mouse click interaction; depending on where you click, one of the two photos will change randomly. View in full screen:
This version might be better because it's not redrawing the photos 60 times per second.
This version just samples the photo randomly and places a sample in each cell of the grid; the photos change based on the mouse position.
This version features stochastic sampling of the photo so that the eye is more frequently displayed; the mouse interaction is the same.
This version uses multiple photographs, choosing a random photograph and then stochastic sampling of that photo; it also changes which photo is being sampled when the mouse is clicked.