Bounding Constraint Propagation for Optical Flow Estimation

The velocity field that represents the motion of object points across an image is called the optical flow field. Optical flow results from relative motion between a camera and objects in the scene. One class of techniques for the estimation of optical flow utilizes a relationship between the motion of surfaces and the derivatives of image brightness (Limb and Murphy, 1975; Cafforio and Rocca, 1976; Fennema and Thompson, 1979; Netravali and Robbins, 1979; Schalkoff, 1979; Lucas and Kanade, 1981; Schunck and Horn, 1981; Thompson and Barnard, 1981; and Schalkoff and McVey, 1982). The major difficulty with gradient-based methods is their sensitivity to conditions commonly encountered in real imagery. Highly textured regions, motion boundaries, and depth discontinuities can all be troublesome for gradient-based methods. Fortunately, the areas characterized by these difficult conditions are usually small and localized.