Hierarchical Elastic Graph Matching for Hand Gesture Recognition

A hierarchical scheme for elastic graph matching applied to hand gesture recognition is proposed. The proposed algorithm exploits the relative discriminatory capabilities of visual features scattered on the images, assigning corresponding weights to each feature. A boosting algorithm is used to determine the structure of the hierarchy of a given graph. The graph is expressed by annotating nodes of interest over the target object to form a bunch graph. Three annotation techniques, manual, semi-automatic, and automatic annotation are used to determine the position of the nodes. The scheme and the annotation approaches are applied to explore hand gesture recognition performance. A number of filter banks are applied to hand gestures images to investigate the effect of using different feature representation approaches. Experimental results show that the hierarchical elastic graph matching (HEGM) approach classified the hand posture with a gesture recognition accuracy of 99.85% when visual features were extracted by utilizing the histogram of oriented gradient (HOG) representation. The results also provide the performance measures from aspect of recognition accuracy to matching benefits, node positions correlation and consistency on three annotation approaches, showing that the semiautomatic annotation method is more efficient and accurate than the other two methods. Keyword: Elastic bunch graph, Graph matching, Feature hierarchy, Feature extraction, Hand gesture recognition