Hierarchical feature based matching for motion correspondence

The authors design a feature based motion correspondence system. They propose a hierarchical grouping process that groups line segments into more complex structures that are easier to match. The hierarchy consists of lines, vertices, edges and surfaces. Matching starts at the highest level of the hierarchy (surfaces) and proceeds to the lowest (lines). Higher level features are easier to match, because they are fewer in number and more distinct in form. These matches then constrain the matches at lower levels. Perceptual and structural relations are used to group matches into islands of certainty. A Truth Maintenance System (TMS) is used to enforce grouping constraints and eliminates inconsistent match groupings. The TMS is also used for reasoning in the presence of uncertainty and to carry out logic revisions necessitated by additions, deletions and confirmations of hypotheses. The hierarchical matching process results in line matches as well as point matches. These then can be used as an input to a motion estimation algorithm