A constrained genetic algorithm for line labelling of line drawings with shadows and table-lines

► Create a cue dictionary by observing the way cues constrain an edge interpretation. ► Formalize the representation of foreground-background scenarios. ► Generalize the cue dictionary to allow for different light source locations. ► Use the cues as soft constraints in an edge labelling algorithm. ► Evaluate the algorithm with drawings with missing, inaccurate and inconsistent cues.