Figure 7

Influence of constraints for augmented AAM fitting. The Euclidean point-to-point errors between tracked and ground-truth landmarks are shown as Tukey boxplots grouped by the type of used constraints for AAM fitting, bird species, camera view, and landmark group. The types of used constraints range from ‘none’ (standard AAMs) to ‘all’ (augmented AAMs). Results are exemplarily shown for a difficult bird species (jackdaws) and an easy scenario (tinamous). In challenging scenarios, all constraints contribute to the final fitting performance, as can be seen for the lower leg landmarks of jackdaws.