Ioan Marius Bilasco

An MPEG-7 framework enhancing the reuse of 3D models

The continuous evolution of computer capacities, as well as the emergence of the X3D standard has recently boosted the 3D domain. Even if efficient tools that support the designers work exist, little attention is paid to the reuse of 3D models. Associating some semantics with 3D contents is an important issue for reusing such contents or pieces of content. In this paper, we address this issue by using a generic semantic annotation model for 3D, called 3DSEAM [Bilasco et al. 2005b] (3D SEmantics Annotation Model). 3DSEAM aims at indexing 3D contents considering visual, geometric and semantic aspects. A generic 3D Annotation Framework (called 3DAF) is proposed in order to manage the semantic annotations of 3D objects. 3DAF is instantiated using an MPEG-7-based architecture. An extension of MPEG-7 that addresses 3D content is used. [Bilasco et al. 2005a].

On indexing of 3D scenes using MPEG-7

The evolving desktop computer capacities and the emergence of the X3D standard offer a new boost to 3D domain. Giving sense to 3D content becomes a major issue specially for reusing such a content extracted from existing 3D scenes. In this paper, we address this issue by proposing a generic semantic annotation model for 3D called 3DSEAM (3D SEmantics Annotation Model). 3DSEAM aims at indexing 3D content considering visual, geometric and semantic aspects. 3DSEAM is instantiated using MPEG-7 extended with 3D specific locators. These locators link the visual, geometric and semantic features of a 3D content to the corresponding X3D fragment.

Semantic-based rules for 3D scene adaptation

3D data is democratizing on the Web as it becomes available to everybody on almost all access devices. Still, 3D data is a heavy medium, as it contains a lot of geometric and texture information. This complexity raises a lot of problems, especially when data initially designed for great capacity access devices, is to be deployed on small devices. Due to the great heterogeneity of access devices and of their users and usages, the adaptation of already designed data is an important issue. In this paper, we present a rule-based adaptation framework that deals with the adaptation of X3D scenes. An adaptation rule indicates a type of adaptation to be applied to a set of objects which fit with the rule criterion. A basic set of adaptation techniques are registered within the framework. The framework is flexible and additional adaptation engines can be registered in order to support large sets of adaptation techniques.

STAMP: A Model for Generating Adaptable Multimedia Presentations

The STAMP model addresses the dynamic generation of multimedia presentations in the domain of Multimedia Web-based Information Systems. STAMP allows the presentation of multimedia data obtained from XML compatible data sources by means of query. Assuming that the size and the nature of the elements of information provided by a data source is not known a priori, STAMP proposes templates which describe the spatial, temporal, navigational structuration of multimedia presentations whose content varies. The instantiation of a template is done with respect to the set of spatial and temporal constraints associated with the delivery context. A set of adaptations preserving the initial intention of the presentation is proposed.

3DSEAM: a model for annotating 3D scenes using MPEG-7

The progress and the continuous evolution of computer capacities, as well as the emergence of the X3D standard have recently boosted the 3D domain. Associating some semantics with 3D contents becomes a major issue specially for reusing such contents or pieces of content after having extracted them from existing 3D scenes. In this paper, we address this issue by proposing a generic semantic annotation model for 3D, called 3DSEAM (3D semantics annotation model). 3DSEAM aims at indexing 3D contents considering visual, geometric and semantic aspects. 3DSEAM is instantiated using MPEG 7 that we have extended with 3D specific locators. These locators link some visual, geometric and semantic features to the corresponding X3D fragments. These features can then be used for indexing and querying.

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

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).

Sémantique et modélisation de scènes 3D

Fools capable of dealing with the near future expansion of the quantity of 3D data available on the Web are now required. Most of the existing 3D models completely lacks of non-functional information, like the semantic annotations that usually enhance and guide the retrieval and the reuse of multimedia data. In this paper, we present the approach that we have chosen for characterising 3D contents as a union of semantic annotations and 3D-related properties (color, geometry) inside a unified model called 3DSEAM. We equally address the generation of 3D scenes where the X3D geometric description is enriched with semantic annotations introduced by using predefined metadata constructs. The choices we made in our approach aim at enhancing the reuse and the adaptation of 3D objects with regard to various contexts of use and applications.

In-situ Quantification of 3D Scene Complexity

This work explores the quantification of the complexity of 3D scenes using frame rate evaluation. Viewpoints are dynamically generated and binded to the target scene in order to reproduce real user actions inside the scene. The SAI technology is used in order to record the observed frame rate. Several evaluation patterns are considered: examine an object, look at the center of the scene, look around a given point. This kind of information is very important because it shows 3D authors, if a specific 3D scene can be played adequately or not for a range of browsers. Indeed, this measure could be used to indicate whether adaptation techniques are to be considered before deploying a scene in a specific context. Authors can also yield interesting results for the designers. Low framerates and hence high complexity in regions that lack of interest for target users imply possible design faults.

Annotating 3D contents with MPEG-7 for reuse purposes

The progress and the continuous evolution of computer capacities, as well as the emergence of the X3D standard have recently boosted the 3D domain. Still, 3D data management remains expensive. Lot of (human and materiel) resources are needed to properly create 3D objects. In order to speed up the construction of new 3D objects, the reuse of existing objects is to be considered. Associating some semantics with 3D contents becomes a major issue specially for reusing such contents or pieces of content after having extracted them from existing 3D scenes. In this paper, we address this issue by proposing a generic semantic annotation model for 3D, called 3DSEAM (3D Semantics Annotation Model). 3DSEAM aims at indexing 3D contents considering visual, geometric, topologic and semantic aspects. We extend MPEG-7 in order to support the localisation of 3D objects. With this extension MPEG-7 can be used in order to instantiate the 3DSEAM model. Thus; through specific 3D locators 3DSEAM can attach some visual, geometric and semantic features with 3D objects defined within X3D fragments. These features can be indexed and then combined in order to formulate complex queries.

STAMP: Adaptable Templates for Synchronized Multimedia Presentations

This paper addresses the adaptation of dynamic and synchronized multimedia presentations built by querying XML compatible data sources. We provide WIS designers with facilities for describing presentations whose content is not known at design time in terms of quantity, but only after the execution of queries. Our approach relies on the definition of a template. A template consists of a model that aims at automatically adapting the multimedia content of a presentation to both the users profile and the characteristics of her/his access device. We show here how a template is built and how adaptations of the presentation are performed when the quantity of information and/or the material capabilities of the access devices (e.g. display size), do not match the templates spatiotemporal specifications.