Search results for " image processing."

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 …

XA2C Framework for XML Alteration/Adaptation

2010

XML has crossed the borders of software engineering and has spread to other areas such as e-commerce, identification, information storage, instant messaging and others. It is used to communicate crucial data over these domains. Thus, allowing non-expert programmers to manipulate and control their XML data is essential. In the literature, this issue has been dealt with from 3 perspectives: (i) XML alteration/adaptation techniques requiring a certain level of expertise to be implemented and are not unified yet, (ii) mashups, which are not formally defined yet and are not specific to XML data, and (iii) XML-oriented visual languages based on structural transformations and data extraction mainl…

On Keyframe Positioning for Pose Graphs Applied to Visual SLAM

2013

International audience; In this work, a new method is introduced for localization and keyframe identification to solve a Simultaneous Localization and Mapping (SLAM) problem. The proposed approach is based on a dense spherical acquisition system that synthesizes spherical intensity and depth images at arbitrary locations. The images are related by a graph of 6 degrees-of-freedom (DOF) poses which are estimated through spherical registration. A direct image-based method is provided to estimate pose by using both depth and color information simultaneously. A new keyframe identification method is proposed to build the map of the environment by using the covariance matrix between raletive 6 DOF…

Performance evaluation of Wireless Sensor Networks based on ZigBee technology in smart home

2013

International audience; Wireless Sensor Networks (WSNs) has diverse application domains such as smart home, smart care, industrial, etc. In this paper, we present a WSN system based on the ZigBee technology (IEEE 802.15.4) in Smart Home. To have a good sensor networks communication implanted in a smart home, studies of operating performance on this network is important. In this work, we investigate the performance of our ZigBee sensor networks. The study of performance is based on measurements of the Received Signal Strength Indicator (RSSI) in different parts of the Home. We will also discuss the impact of electromagnetic noise on the communication performance of a ZigBee Sensor Network in…

Development of new techniques for super-resolution video sequences : Towards a real-time implementation on Smart Camera

2020

These thesis works are part of an european project aiming to design a very hight resolution (8k) video camera. Within this project our team had the task of working on two technological aspects: (1) the design of a demonstrator carrying out a realtime deconvolution of a video stream coming from a very high resolution camera created by the consortium , (2) the design of a prototype allowing to increase the resolution and the level of detail of video streams from an input resolution of 4k to 8k using Super Resolution (SR) methods. This manuscript mainly presents the work related to the creation of the prototype realizing a Super Resolution method. In order to be able to assess the qualitative …

Adéquation Algorithme architecture : Aspects logiciels, matériels et cognitifs

2008

Les travaux présentés dans le cadre de cette Habilitation à Diriger des Recherches s'inscrivent principalement dans la problématique dite d'" Adéquation Algorithme Architecture ". Ils ont pour objectif commun la mise en œuvre de systèmes matériels et logiciels dédiés à la vision artificielle à fortes contraintes temporelles. Ils se focalisent sur différents aspects cruciaux tels que l'acquisition d'images par des capteurs dédiés, le développement et la programmation d'architectures optimisées de traitement des images et l'implantation d'algorithmes de traitement du signal et d'images en temps réel sur ces architectures.

Convolutional Neural Network for Blind Mesh Visual Quality Assessment Using 3D Visual Saliency

2018

International audience

Dispositifs d’imagerie multi-spectrale pour la détection et le contrôle des adventices

2007

National audience; pas de résumé

Multispectral imaging for computer vision

2018

Refitting solutions promoted by $\ell_{12}$ sparse analysis regularization with block penalties

2019

International audience; In inverse problems, the use of an $\ell_{12}$ analysis regularizer induces a bias in the estimated solution. We propose a general refitting framework for removing this artifact while keeping information of interest contained in the biased solution. This is done through the use of refitting block penalties that only act on the co-support of the estimation. Based on an analysis of related works in the literature, we propose a new penalty that is well suited for refitting purposes. We also present an efficient algorithmic method to obtain the refitted solution along with the original (biased) solution for any convex refitting block penalty. Experiments illustrate the g…