Reverse Perspective

Abstract

Basic idea: We see the world in 3-dimensions even though the image projected onto the back of our eye is 2-dimensional. How do we do this? The short answer is that we do this by relying on a variety of different depth cues. What happens when these cues are put into conflict? Definitions: Monocular cues-depth cues needing only one eye-also called pictorial depth cues because they are often used in paintings to depict depth (e.g., perspective and shading) Linear perspective-parallel lines appear to converge in the distance (e.g., the sidewalks of the Champs Elysee in Paris appear to converge at a vanishing point at the horizon) Motion parallax-a monocular depth cue that relies on observer motion through a scene to obtain multiple views of the scene needed to perceive its three dimensionality Binocular cues-depth cues that can only be seen when viewed with both eyes