Limitations and Future works

Our skeleton extraction algorithm is capable to generate the compact skeleton for the triangle-mesh models, especially the models of articulated shape. For example, the animal models and the human models are articulated. Generally speaking, the articulated models are composed by the generalized cylinder components. For such models, the MSP function can provide reason-able information and generate more skeleton-like mesh. But for the models of plane shape or the models that own much prominent features such as the dancing-children and the gargoyle models, the MSP function is limited to the local features and can not provide global informa-tion. So that the skeleton meshes of these models are much similar to the medial axis. Through this kind of skeleton mesh, we will generate more coarse skeleton. Furthermore, because the MSP function can handle closed models only, we are not able to extract any open meshes to generate skeletons.

In the future, we would like to enhance our skeleton extraction algorithm from two direc-tions. The first direction is to change the measurement of MSP functions to improve the quality of skeleton mesh. The MSP function measure the local volume by the slice with minimum

perimeter. But the slice with minimum perimeter does not imply that the MSP slice must exist an skeleton node. If we can enhance the MSP functions, we can obtain more accurate skeleton mesh and better skeleton results.

The second direction is to apply some refinements on the skeleton mesh directly. We could use the spatial coherence of the skeleton mesh to update the skeleton nodes of low confidences.

We update the nodes of low confidence close to the adjacent nodes of high confidences. This could be achieve more thinned skeleton mesh. Figure 6.1 show our testing results of the skeleton mesh which had been refined using the spatial coherence. Clearly, there exist some problems of the skeleton mesh. Such as the design of error metrics and constraints. Besides the two direc-tions of the future work, we would also like to apply our skeleton results to some applicadirec-tions such as the animation and the segmentation and hope to assist the progress of another topic.

(a) Horse model. (b) Armadillo model

Figure 6.1: Spatial Coherence refined skeleton mesh.

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