Spatio-Temporal Detection of Fine-Grained Dyadic Human Interactions

We introduce a novel spatio-temporal deformable part model for offline detection of fine-grained interactions in video. One novelty of the model is that part detectors model the interacting individuals in a single graph that can contain different combinations of feature descriptors. This allows us to use both body pose and movement to model the coordination between two people in space and time. We evaluate the performance of our approach on novel and existing interaction datasets. When testing only on the target class, we achieve mean average precision scores of 0.82. When presented with distractor classes, the additional modelling of the motion of specific body parts significantly reduces the number of confusions. Cross-dataset tests demonstrate that our trained models generalize well to other settings