Superquadrics for 3-D shape indexing language

With the recent development of input, presentation, and processing technologies for three-dimensional (3-D) images as the background, the demand for the effective storage and management of 3-D images is expected to increase. This paper aims at the effective storage and retrieval of the 3-D images and proposes a 3-D shape indexing by the superquadrics. The features of super-quadrics are that the expression is simple and various shapes can be represented using a smaller number of parameters. To examine the applicability of the function, the technique based on superquadrics is compared with conventional 3-D modeling from the viewpoint of the power for representing the feature and shape as the technical requirement for the indexing. The purpose of the conventional modeling technique is to represent the shape from the visual sensation. However, this resulted in a problem whereby it is difficult to determine the shape from the modeled data structure. By contrast, with superquadrics, the functional parameters are easily related to the shape; thus realizing a sufficient applicability as the indexing. An image retrieval system is constructed using the superquadrics parameters as the indexes, and the usefulness of the proposed indexing technique is demonstrated.