Françoise Morvan, ed., Les Contes de Luzel. Légendes chrétiennes de la Basse-Bretagne

Cet ouvrage est le quinzième volume de l’édition des œuvres de François-Marie Luzel (1821-1895) qui, commencée en 1994, devrait en comprendre vingt-cinq. Il rassemble soixante-treize pièces de littérature orale, collectées de 1847 à 1873, réparties selon les sept entrées proposées par le folkloriste, et qui recoupent assez largement la classification suivie par Marie-Louise Tenèze dans le quatrième tome du catalogue du Conte populaire français consacré aux contes religieux. Parmi ces entrées,..

Building DSLs with AMMA/ATL, a Case Study on SPL and CPL Telephony Languages

International audienceDomain-Specific Languages (DSLs) enable more concise and readable specifications than General Purpose Languages (GPLs). They are for this reason increasingly used. This DSL approach presents, however, many challenges. One of them is the prototyping and implementation of the numerous DSLs that are required to replace a single GPL. This work presents a case study of implementing two telephony languages: SPL and CPL. It shows how a DSL building framework like AMMA can be used to this purpose

Optimisation jointe de la chaîne codage/débruitage pour les images satellite

National audienceIn this paper, we propose to study the problem of optimal noisy source coding/denoising. This problem can be formulated as an optimization problem where the criterion to minimize is the global distortion, that is the error between the noise-free image and the denoised image. This problem is challenging since a global optimization is usually difficult to perform as the global fidelity criterion needs to be optimized in the same time over the sets of both coding and denoising parameters. We show here how to express the global distortion in closed-form and we present an algorithm to minimize this distortion with respect to these parameters. We show results of this joint optimization algorithm on classical test images and on a high dynamic range image, visually and in a rate-distortion sense.Dans ce travail, nous proposons d'étudier le problème du codage/débruitage optimal d'une source bruitée. Ce problème peut se formaliser comme un problème d'optimisation où le critère à minimiser est la distorsion globale, c'est-à-dire l'erreur entre l'image d'origine non bruitée et l'image décodée débruitée. Ce problème est complexe à traiter car une optimisation globale est habituellement difficile à effectuer puisque le critère global doit être optimisé en même temps par rapport aux paramètres de codage et de débruitage. Nous montrons ici comment écrire analytiquement les différents termes de la distorsion globale et nous présentons un algorithme pour minimiser cette distorsion par rapport à ces paramètres. Nous montrons des résultats de cet algorithme d'optimisation jointe sur des images classiques et sur une image satellite haute dynamique, visuellement et d'un point de vue débit-distorsion

La chaîne image SPOT5 THR : un exemple d'optimisation globale

- Issu de la filière SPOT, le satellite de télédétection optique SPOT5 s'en démarque par un mode d'échantillonnage quinconce adapté à la Fonction de Transfert de Modulation (FTM) de l'instrument et généré par un détecteur spécifique comportant deux barrettes CCD décalées dans le plan focal. En raison des faibles valeurs de la FTM pour les hautes fréquences spatiales, les images produites par un tel système sont floues et nécessitent un traitement sol complexe d'interpolation quinconce, de déconvolution linéaire et de débruitage par seuillage de coefficients de paquets d'ondelettes

Processing Domain-Specific Modeling Languages: A Case Study in Telephony Services

International audienceThe Domain-Specific Language (DSL) approach is being actively studied from both a software engineering viewpoint and a programming language viewpoint. It is being successfully applied to a variety of areas such as banking, graphics and networking. Yet, the concept of a DSL is still very vague, making both its applicability and implementation difficult. This paper introduces a layered approach to DSLs where (1) domain experts are provided with Domain-Specific Modeling Languages (DSMLs), requiring no programming skills and (2) implementation experts deal with Domain-Specific Programming Languages (DSPLs) that require a programming background but abstracts over the intricacies of underlying technologies. By separating domain and implementation concerns, we show that our layered DSL approach enables high-level tools to be used to both compile and reason about DSML programs. Compilation and program verification amount to defining high-level generative processes. We illustrate our approach with the domain of telephony service creation. We introduce a DSML for service creation and demonstrate the ease of compiling DSML programs using the Stratego/XT program transformation environment. Two compilation processes are defined for DSML programs targeting (1) a DSPL, illustrating a high-level compilation process and (2) the TLA+ specification language, exemplifying the verification of domain-specific properties

La compression embarquée d'images pour les systèmes optiques d'observation spatiale

La compression embarquée est devenue une étape indispensable pour optimiser les ressources nécessaires à l'enregistrement et à la transmission des images vers les stations de réception. Les performances, en amélioration constante, des algorithmes de compression et les progrès rapides des technologies micro-électroniques embarquables permettent de disposer à bord de techniques de compression très efficaces. Nous décrivons dans cet article les différents algorithmes de compression, utilisés ou en cours d'étude pour des missions spatiales ainsi que les résultats obtenus

Staging Telephony Service Creation: A Language Approach

International audienceThe open-endedness of telephony platforms is creating expectations among users, ranging from end-users to administrators, to create services dedicated to their activities. Not only is the population of developers heterogeneous, but the technologies underlying modern telephony range over a variety of areas such as multimedia, databases, web services, and distributed systems. This situation drastically widens the expertise required for service creation. We propose an approach to coping with the heterogeneity of both the service developers and the technologies underlying modern telephony. Our approach is based on programming languages. It consists of providing a language that is specific to each developer community with respect to its expertise (e.g., programming skills) and the target application area (e.g., administration). Such languages, called Domain-Specific Languages (DSLs), are organized in layers, accounting for abstraction levels. Our layered approach to telephony service creation is illustrated by two high-level DSLs for end-user service creation, requiring no programming skills, and an expressive DSL enabling the development of expert-level telephony services. We show that layering DSLs greatly facilitates their implementation and verification of telephony-specific properties by leveraging on high-level tools

Building DSLs with AMMA/ATL, a Case Study on SPL and CPL Telephony Languages

International audienceDomain-Specific Languages (DSLs) enable more concise and readable specifications than General Purpose Languages (GPLs). They are for this reason increasingly used. This DSL approach presents, however, many challenges. One of them is the prototyping and implementation of the numerous DSLs that are required to replace a single GPL. This work presents a case study of implementing two telephony languages: SPL and CPL. It shows how a DSL building framework like AMMA can be used to this purpose

A comparative study of SIP programming interfaces

International audienceThe Session Initiation Protocol (SIP) is a signalling protocol for Internet Telephony, multimedia conferenc- ing, and instant messaging. The behavior of SIP platforms can be configured thanks to various programming interfaces. In this paper, we present a study of different existing SIP platforms. From this study, we identify key requirements that must be fulfilled by a SIP programming interface. We discuss existing solutions and propose to introduce a language approach to addressing these needs

Joint coding-denoising optimization of noisy images

In this paper, we propose to study the problem of noisy source coding/denoising. The challenge of this problem is that a global optimization is usually difficult to perform as the global fidelity criterion needs to be optimized in the same time over the sets of both coding and denoising parameters. Most of the bibliography in this domain is based on the fact that, for a specific criterion, the global optimization problem can be simply separated into two independent optimization problems: The noisy image should be first optimally denoised and this denoised image should then be optimally coded. In many applications however, the layout of the acquisition imaging chain is fixed and cannot be changed, that is a denoising step cannot be inserted before coding. For this reason, we are concerned here with the problem of global joint optimization in the case the denoising step is performed, as usual, after coding/decoding. In this configuration, we show how to express the global distortion as a function of the coding and denoising parameters. We present then an algorithm to minimize this distortion and to get the optimal values of these parameters. We show results of this joint optimization algorithm on classical test images and on a high dynamic range image, visually and in a rate-distortion sense