Shape-Similarity Comparison of 3D Models Using Alpha Shapes

As the number of in-house and public-domain 3D shape models increase, importance of shape-similarity based search and retrieval for 3D shapes models has increased rapidly. In this paper, we describe our preliminary findings in applying a multiresolution analysis technique to the task of shape similarity comparison of polygon soup models. We used the 3D alpha shapes algorithm to create a multiresolution hierarchy of shapes from the given 3D model. We then applied a (single resolution) shape descriptor to each of the models at multiple resolution levels to derive a multiresolution shape descriptor. According to our evaluation experiments, the retrieval performance of our multiresolution descriptor outperformed its single resolution counterpart, proving the effectiveness of the basic approach.