How do we perceive?

How do I know I’m looking at a 3D scene?

Height in Plane: This car appears to be floating Linear Perspective: Straight lines of the road come together at the horizon Relative Size: Ringo is about 4 times as big as the man on the pavement Occlusion: George’s body is covering up the white car

The image our eyes receive is 2D but we need to change it onto a 3D picture. We use depth cues to do this. A depth cue is a feature of an image which indicates distance. Monocular Depth Cue: A way of detecting depth or distance which will work with just one eye Binocular Depth Cue: A way of detecting depth or distance which requires two eyes in order to work Depth Cues

Monocular Depth Cues:

Visual Constancy Visual constancy is our ability to perceive that an object remains the same, even when the object projects different images onto our retinas in our eyes. There are different types of visual constancy, for example shape, colour, size, brightness and location.

Binocular Depth Cues

Your brain receives two slightly different images from your eyes Your brain receives two slightly different images from your eyes. It can compare these images to perceive depth There are two main ways in which binocular cues work Convergence Retinal Disparity Binocular Vision

Convergence We move our eye muscles in different ways if we look at something close up or further away. The close the object the more the eye muscles have to move the eye balls in their sockets. This muscle movement provides the brain with depth information

Retinal Disparity The two eyes send different impulses to the brain – your brain receives two different images. The further away something is, the more similar these two images are. The closer the image is, the more different the two images are

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