Tracking points and line segments in image sequences

The author examines different constraints which can be used to find the correspondences between line segments in an image sequence. These constraints are imposed by the continuity of the 3-D motion and also by certain types of motions. The author derives simple equations which relate corresponding tokens in three consecutive images when the 3-D motion is a translation. Next, he describes an algorithm for matching line segments when the motion of the camera is approximately known and presents some experimental results. If a camera moving in a stationary environment is considered, an image motion is related to the location of the corresponding object in space with respect to the instantaneous axis of translation. The author performs a geometrical analysis of this relationship and introduces concepts for this analysis. It is noted that this relationship is useful for tracking objects in the field of view