Static Stereo

Abstract

Recovering depth is a central problem in three-dimensional perception. Static stereo is a primary means for recovering depth from two images taken from different viewpoints. As early as 1838, Sir Charles Wheatstone [Whe38] invented a stereoscope which uses the slight differences of two static pictures to generate a vivid sense of depth. This invention is based on the phenomenon of stereopsis, which arises from the fact that human eyes view the visual world from slightly different angles. As shown in Figure 3.1, when an observer looks at a point A in space, the images of A projected on the centers of the left and right foveas are L _A and R _A , respectively. L _A and R _A are called corresponding points. Now suppose there is another point B in space which is farther from the observer than point A. Point B produces two images L _B and R _B on the retinas some distance from the centers of the foveas. The distances from L _B to the center of the left fovea and from R _B to the center of the right fovea are different. The disparity in the distance varies with the depth of the point in space. The three-dimensional information can be decoded from the binocular disparities.