LINGRAND , Diane

This paper addresses the optimal recovery of the displacement and projection parameters from uncalibrated monocular video sequences. We study the particular cases of camera and objects displacements and camera projection in order to extract an optimized parameterization of the problem of parameters recovery for each cases. This work follows...

Part of the robotic vision framework, this thesis focuses on uncalibrated monocular video sequence analysis, taking singular physical cases into account (camera models, internal camera parameter evolution, object displacements, scene structure) that leads to specific equations. Singularities may allow us to retrieve more movement or structure...

For decades, there has been an intensive research effort in the Computer Vision community to deal with video sequences. In this paper, we present a new method for recovering a maximum of information on displacement and projection parameters in monocular video sequences without calibration. This work follows previous studies on particular cases...

Les approximations de la projection perspective étudiées dans ce rapport, projections para-perspective, ortho-perspective et orthographique, peuvent être considérées à la fois comme des approximations géométriques et des approximations numériques (développement limité d'ordre précisé). Nous avons examiné les simplifications apportées par ces...

Cet ouvrage est une introduction pragmatique au traitement d'images. Il passe en revue les algorithmes classiques de traitement d'images tout en les rapprochant d'applications concrètes. Il vise également à démystifier un certain nombre de techniques récentes dont les fondements théoriques sont complexes mais qui peuvent être abordées de façon...

Deformable contours are now widely used in image segmentation, using different models, criteria and numerical schemes. Some theoretical comparisons between some deformable model methods have already been published. Yet, very few experimental comparative studies on real data have been reported. In this paper,we compare a levelset with a B-spline...

This study is aimed at developing a method of analysis of the 3D structure of a scene considering a monocular image sequence, with an uncalibrated camera -as for an active visual system- and using a continuous model of motion. Surprisingly perhaps, this problem has not been studied much in literature except \cite{vieville-faugeras:95}, but only...

In the present paper, we review and complete the equations and the formalism which allow to achieve a minimal parameterization of the retinal displacement for a monocular visual system without calibration. Considering the emergence of active visual systems for which we {\bf can not} consider that the calibration parameters are either known or...

Production grids exhibit high failure rates ham- pering the development of many large scale scientific ap- plications. End users require robust experiment production environments ensuring efficient resubmission of failed tasks. Proper parameterization of resubmission strategies is a com- plex problem that depends on the non-stationary workload...

This paper targets with applications running on mobile devices and using context informations. Following previous studies from other authors, we extend the notion of context area replacing distance function by cost function. Using this extension, we exhibit three different modes of selection and demonstrate their differences on a mobile...

As Deep Learning tackles complex tasks like trajectory forecasting in autonomous vehicles, a number of new challenges emerge. In particular, autonomous driving requires accounting for vast a priori knowledge in the form of HDMaps. Graph representations have emerged as the most convenient representation for this complex information....

We revisit the problem of parameter estimation in computer vision, reconsideri- ng and implementing what may be called the Kanatani's estimation reconsidering and implementing what may be called the Kanatani's estimation method, presented here as a simple optimisation problem, so (a) without any method, presented here as a simple optimisation...

Levelset methods were introduced in medical images segmentation by Malladi et al in 1995. In this paper, we propose several improvements of the original method to speed up the algorithm convergence and to improve the quality of the segmentation in the case of cardiac gated SPECT images. We studied several evolution criterions, taking into...

Production-grid users experience many system faults as well as high and variable latencies due to the scale, complexity and sharing of such infrastructures. To improve performance, they adopt different submission strategies, that are potentially aggressive for the infrastructure. This work studies the impact of three different strategies. It is...

In this paper, we study grid jobs latency. Together with outliers, latency highly impacts applications performance on production grids, due to its order of magnitude and important variations. It is particularly prejudicial for determining the expected duration of applications handling a high number of jobs and it makes outliers detection...

In this paper, we study grid job submission latencies. The latency highly impacts performances on production grids, due to its high values and variations as well as the presence of outliers. It is particularly prejudicial for determining the status and expected duration of jobs. In a previous work, a probabilistic model of the latency is...

This work is realized within the scope of a general attempt to understand parametric adaptation, regarding visual perception. The key idea is to analyze how we may use multi-model parametric estimation as a 1st step towards categorization. More generally, the goal is to formalize how the notion of ``objects'' or ``events'' in an application may...

This paper targets with applications running on mobile devices. We aim at developing a formalism and a framework to simplify the development of applications taking into account the context in which they are running, whatever this context may be. Following previous studies from other authors, we extend the notion of context area using distance...

Grid are promising tools to tackle massively parallel medical applications such as medical image databases indexation but their complexity make the optimization of computation tasks and the design of computing models difficult. We tackle this complexity by a probabilistic approach. We have shown that a probabilistic model of the computing tasks...

Production-grid users experience many system faults as well as high and variable latencies due to the scale, complexity and sharing of such infrastructures. To improve performance, they adopt different submission strategies, that are potentially aggressive for the infrastructure. This work studies the impact of three different strategies. It is...

International audience