Metrics for functional and aesthetic label layouts

Co-referential relations between textual and visual elements in illustrations can be encoded efficiently through textual labels. The labels support students to learn unknown terms and focus their attention on important aspects of the illustration; while a functional and aesthetic label layout aims at guaranteeing the readability of text strokes as well as preventing the referential mismatches. By analyzing a corpus of complex label layouts in hand-drawn illustrations, a classification of label layout styles and several metrics for functional requirements and aesthetic attributes were extracted. As the choice of a specific layout style seems largely determined by individual preferences, a real-time layout algorithm for internal and external labels balances conflicting user-specific requirements, functional and aesthetic attributes.