Towards Geospatial Queries in a Semantic Digital Library for 3D Data

Abstract

The evolution of the computing power as well as the success of standards such as X3D point to a future omnipresence of 3D in the multimedia world. A broad panoply of tools assisting designers when building realistic 3D scenes exists. In a near future, a new challenge will be to control the quantity of 3D contents that will be available. For instance, large amounts of 2D or 3D geographic data are spread all over the Internet. Nevertheless, appropriate description techniques and tools for the deployment and the retrieval of such data are still lacking. Our global objective is to propose a geographic digital library which can be exploited for describing, annotating and indexing geographic contents using geometric and topologic descriptions, geographic and appearance features, and semantics. Descriptions, annotations, and indexations are then exploited in queries to retrieve contents. The existing 3D scene description languages are generally free of any semantic information which could improve the management of 3D data (and especially research and re-use). In this paper, we propose the construction of geographic 3D data warehouses managed by a semantic digital library 3DSDL (3D Semantic Digital Library). This library, through a standardized communication interface, gives access to all the 3D models indexed in the warehouse and facilitates their exploitation. Each object is characterized by a set of both semantic and geographic annotations and some common features (colour, geometry, and topology).