Search results for "Image"
showing 10 items of 6818 documents
Adding Semantic Extension to Wikis for Enhancing Cultural Heritage Applications
2011
International audience; Wikis are appropriate systems for community-authored content. In the past few years, they show that are particularly suitable for collaborative works in cultural heritage. In this paper, we highlight how wikis can be relevant solutions for building cooperative applications in domains characterized by a rapid evolution of knowledge. We will point out the capabilities of semantic extension to provide better quality of content, to improve searching, to support complex queries and finally to carry out di fferent type of users. We describe the CARE project and explain the conceptual modeling approach. We detail the architecture of WikiBridge, a semantic wiki which allows …
Query-preserving watermarking of relational databases and XML documents
2011
Watermarking allows robust and unobtrusive insertion of information in a digital document. During the last few years, techniques have been proposed for watermarking relational databases or Xml documents, where information insertion must preserve a specific measure on data (for example the mean and variance of numerical attributes). In this article we investigate the problem of watermarking databases or Xml while preserving a set of parametric queries in a specified language, up to an acceptable distortion. We first show that unrestricted databases can not be watermarked while preserving trivial parametric queries. We then exhibit query languages and classes of structures that allow guarante…
Vertex Distinguishing Edge- and Total-Colorings of Cartesian and other Product Graphs
2012
International audience; This paper studies edge- and total-colorings of graphs in which (all or only adjacent) vertices are distinguished by their sets of colors. We provide bounds for the minimum number of colors needed for such colorings for the Cartesian product of graphs along with exact results for generalized hypercubes. We also present general bounds for the direct, strong and lexicographic products.
Semantic Mappings in Description Logics for Spatio-temporal Database Schema Integration
2005
International audience; The interoperability problem arises in heterogeneous systems where different data sources coexist and there is a need for meaningful information sharing. One of the most representive realms of diversity of data representation is the spatio-temporal domain. Spatio-temporal data are most often described according to multiple and greatly diverse perceptions or viewpoints, using different terms and with heterogeneous levels of detail. Reconciling this heterogeneity to build a fully integrated database is known to be a complex and currently unresolved problem, and few formal approaches exist for the integration of spatio-temporal databases. The paper discusses the interope…
Multiple Structured Light-Based Depth Sensors for Human Motion Analysis: A Review
2012
Human motion analysis is an increasingly important active research domain with various applications in surveillance, human-machine interaction and human posture analysis. The recent developments in depth sensor technology, especially with the release of the Kinect device, have attracted significant attention to the question of how to take advantage of this technology in order to achieve accurate motion tracking and action detection in marker-less approaches. In this paper, we review the benefits and limitations deriving from the adoption of structured light-based depth sensors in human motion analysis applications. Surveying the relevant literature, we have identified in calibration, interf…
Evolutionary-based 3D reconstruction using an uncalibrated stereovision system: application of building a panoramic object view
2010
In this paper, we propose an original evolutionary-based method for 3D panoramic reconstruction from an uncalibrated stereovision system (USS). The USS is composed of five cameras located on an arc of a circle around the object to be analyzed. The main originality of this work concerns the process of the calculation of the 3D information. Actually, with our method, 3D coordinates are directly obtained without any prior estimation of the fundamental matrix. The method operates in two steps. Firstly, points of interest are detected in pairs of images acquired by two consecutive cameras of the USS are matched. And secondly, using evolutionary algorithms, we jointly compute the transformed matr…
Study and Comparison of Surface Roughness Measurements
2014
Journées du Groupe de Travail en Modélisation Géométrique (GTMG'14), Lyon; This survey paper focus on recent researches whose goal is to optimize treatments on 3D meshes, thanks to a study of their surface features, and more precisely their roughness and saliency. Applications like watermarking or lossy compression can benefit from a precise roughness detection, to better hide the watermarks or quantize coarsely these areas, without altering visually the shape. Despite investigations on scale dependence leading to multi-scale approaches, an accurate roughness or pattern characterization is still lacking, but challenging for those treatments. We think there is still room for investigations t…
Étude et optimisation d'un système d'annulation d'écho pour répéteur de radiocommunication
2012
International audience; Le phénomène d'écho en radio-fréquence (RF) se produit au sein d'un répéteur iso-fréquence (IF) lorsque l'isolation entre l'antenne d'émission et l'antenne de réception est insuffisante. L'objectif de ces travaux est de trouver un système d'identification et d'annulation d'écho, en se basant sur le traitement avancé du signal. Cette solution doit être implémenatable matériellement, sur un cir- cuit programmable type FPGA, l'objectif est de travailler en temps réel. La vitesse de convergence des algorithmes, leurs coûts en terme de ressources matérielles et leurs robustesses aux bruits font partie de l'optimisation recherchée. Cette solution doit être utilisable pour …
Compression embarquée temps réel pour caméras rapides
2005
Les caméras rapides sont de puissants outils pour étudier, par exemple, la dynamique des fluides ou le déplacement des pièces mécaniques lors d'un processus de fabrication. Nous décrivons dans ce papier, un nouveau type de caméra rapide possédant un fonctionnement original. En effet, outre le fait qu'elle utilise comme d'autres caméras, la grande flexibilité des capteurs CMOS en termes d'acquisition (ROI), elle est novatrice au niveau du transfert des données. Celles-ci pouvant être à la fois traitées et/ou compressées en temps réel au sein même de la caméra. Le transfert peut s'effectuer alors à l'aide d'une simple connection série de type USB 2.0. On réalise ainsi l'économie d'une mémoire…
Generic heuristics on GPU to superpixel segmentation and application to optical flow estimation
2020
Finding clusters in point clouds and matching graphs to graphs are recurrent tasks in computer science domain, data analysis, image processing, that are most often modeled as NP-hard optimization problems. With the development and accessibility of cheap multiprocessors, acceleration of the heuristic procedures for these tasks becomes possible and necessary. We propose parallel implantation on GPU (graphics processing unit) system for some generic algorithms applied here to image superpixel segmentation and image optical flow problem. The aim is to provide generic algorithms based on standard decentralized data structures to be easy to improve and customized on many optimization problems and…