Human gesture recognition of dynamic skeleton using graph convolutional networks

In this era, intelligent vision computing has always been a fascinating field. With the rapid development in computer vision, dynamic gesture-based recognition systems have attracted significant attention. However, automatically recognizing skeleton-based human gestures in the form of sign language is complex and challenging. Most existing methods consider skeleton-based human gesture recognition as a standard video recognition problem, without considering the rich structure information among both joints and gesture frames. Graph convolutional networks (GCNs) are a promising way to leverage structure information to learn structure representations. However, adopting GCNs to tackle such gesture sequences both in spatial and temporal spaces is challenging as graph could be highly nonlinear and complex. To overcome this issue, we propose the spatiotemporal GCNs model to leverage the powerful spatiotemporal correlations to adaptively construct spatiotemporal graphs, called Aegles. Our method could dynamically attend to relatively significant spatiotemporal joints and construct different graphs, including spatial, temporal, and spatiotemporal graph, and well capturing the structure information in gesture sequences. Besides, we introduce the second-order information of the gesture skeleton data, i.e., the length and orientation of bones, to improve the representation of human hands and fingers. In addition, with the public sign language datasets, we use OpenPose technology to extract human gesture skeleton and obtain human skeleton video, building four skeleton-based sign language recognition datasets. Experimental results show that this Aegles outperforms the state-of-the-art ones and that the spatiotemporal correlations effectively boost the performance of human gesture recognition.