5. Conclusions and future work
In this paper, we propose a novel 3D descriptor for mesh co-segmentation named the “volumetric shape context” (VSC), which describes the volume distribution of a mesh. The performance of this descriptor relies on the auxiliary orientations extracted from the mesh; therefore, we also propose an interactive method and an automatic context-based method of estimating the auxiliary orientations. The experimental results prove that the VSC offers state-of-the-art descriptiveness and can significantly improve the results of segmentation and labeling when it is employed in combination with other descriptors, regardless of which auxiliary orientation estimation method is applied. Although the VSC obtained using the automatic context-based auxiliary orientation estimation method has been proven to be descriptive, the context-based method was not meticulously designed. In our future work, we plan to further improve the performance of the context-based method. For example, the symmetry of the models could be considered. At present, we select the best direction from among 6 possible directions; however, we could also design an algorithm to select the best direction from among all possible directions. Moreover, the consistency of the auxiliary orientations is still an open problem, and the VSC would benefit from the proposal of other effective automatic methods for their extraction. The VSC is designed for use in mesh co-segmentation, including supervised, unsupervised and semi-supervised approaches. In our experiments, the VSC was successfully applied in a supervised approach, but the parameters used in our experiments may not be suitable for use in unsupervised or semi-supervised approaches. Therefore, it will be necessary to investigate what values of the parameters are most suitable in these cases.