Motion capture (Mocap) data are widely used as time series to study human movement. Indeed, animation movies, video games, and biomechanical systems for rehabilitation are significant applications related to Mocap data. However, classifying multi-channel time series from Mocap requires coding the intrinsic dependencies (even nonlinear relationships) between human body joints. Furthermore, the same human action may have variations because the individual alters their movement and therefore the inter/intraclass variability. Here, we introduce an enhanced Hilbert embedding-based approach from a cross-covariance operator, termed EHECCO, to map the input Mocap time series to a tensor space built from both 3D skeletal joints and a principal component analysis-based projection. Obtained results demonstrate how EHECCO represents and discriminates joint probability distributions as kernel-based evaluation of input time series within a tensor reproducing kernel Hilbert space (RKHS). Our approach achieves competitive classification results for style/subject and action recognition tasks on well-known publicly available databases. Moreover, EHECCO favors the interpretation of relevant anthropometric variables correlated with players’ expertise and acted movement on a Tennis-Mocap database (also publicly available with this work). Thereby, our EHECCO-based framework provides a unified representation (through the tensor RKHS) of the Mocap time series to compute linear correlations between a coded metric from joint distributions and player properties, i.e., age, body measurements, and sport movement (action class).

No abstract

No abstract

No abstract

Abstract-Patellofemoral pain syndrome (PFPS) is one of the most com-mon disorders in the knee that occurs with a higher incidence in women than men. Q-angle and A-angle as well as alignment and flexion angle of bending were considered in this study as kinematic variables. The hypothesis is that patients with changes in alignment variables are more likely to have pain in the patellofemoral joint. To verify this, we worked with patients with PFPS which was compared with control patients. No significant difference in angle A and the flexion angle of the knee were found, but a significant difference was found in Q-angle.