Reconnaisance de gestes dynamiques de la main - De la création de descripteurs aux récentes méthodes d’apprentissage profond
Quentin de Smedt · HAL (Le Centre pour la Communication Scientifique Directe) · 2017
Hand gestures are the most natural and intuitive non-verbal communica- tion medium while using a computer, and related research efforts have recently boosted interest. Additionally, data provided by current com- mercial inexpensive depth cameras can be exploited in various gesture recognition based systems. The area of hand gesture analysis covers hand pose estimation and gesture recognition. Hand pose estimation is con- sidered to be more challenging than other human part estimation due to the small size of the hand, its greater complexity and its important self occlusions. Beside, the development of a precise hand gesture recognition system is also challenging due to high dissimilarities between gestures derived from ad-hoc, cultural and/or individual factors of users. First, we propose an original framework to represent hand gestures by using hand shape and motion descriptors computed on 3D hand skeletal fea- tures. We use a temporal pyramid to model the dynamic of gestures and a linear SVM to perform the classification. Additionally, we create the Dynamic Hand Gesture dataset containing 2800 sequences of 14 gesture types. Evaluation results show the promising way of using hand skele- tal data to perform hand gesture recognition. Experiments are carried out on three hand gesture datasets, containing a set of fine and coarse heterogeneous gestures. Furthermore, results of our approach in terms of latency demonstrated improvements for a low-latency hand gesture recog- nition systems, where an early classification is needed. Then, we extend the study of hand gesture analysis to online recognition. Using a deep learning approach, we employ a transfer learning strategy to learn hand posture and shape features from depth image dataset originally created for hand pose estimation. Second, we model the temporal variations of the hand poses and its shapes using a recurrent deep learning technology. Finally, both information are merged to perform accurate prior detection and recognition of hand gestures. Experiments on two datasets demon- strate that the proposed approach is capable to detect an occurring gesture and to recognize its type far before its end.