A unified view on patch aggregation

Patch-based methods are widely used in various topics of image processing, such as image restoration or image editing and synthesis. Patches capture local image geometry and structure and are much easier to model than whole images: in practice, patches are small enough to be represented by simple multivariate priors. An important question arising in all patch-based methods is the one of patch aggregation. For instance, in image restoration, restored patches are usually not compatible, in the sense that two overlapping restored patches do not necessarily yield the same values to their common pixels. A standard way to overcome this difficulty is to see the values provided by different patches at a given pixel as independent estimators of a true unknown value and to aggregate these estimators. This aggregation step usually boils down to a simple average , with uniform weights or with weights depending on the trust we have on these different estimators. In this paper, we propose a probabilistic framework aiming at a better understanding of this crucial and often neglected step. The key idea is to see the aggregation of two patches as a fusion between their models rather than a fusion of estimators. The proposed fusion operation is pretty intuitive and generalizes previous aggregation methods. It also yields a novel interpretation of the Expected Patch Log Likelihood (EPLL) proposed in [40

Étude du problème d'agrégation : fusion de patchs et barycentres de Wasserstein généralisés

This thesis is focused on patch-based methods, a particular type of image processing algorithm. These methods include a step called aggregation, which consists in reconstructing an image from a set of overlapping patches and statistical models on these patches. The aggregation step is formalized here as a fusion operation on distributions living on different subspaces but not disjoint. We introduce first a new fusion method based on probabilistic considerations, directly applied to the aggregation problem. It turns out that this operation can also be formulated in a more general setup, like a generalization of a barycenter problem between distributions. This lead us to study this new problem from an optimal transport theory perspectiveCette thèse porte sur une classe particulière d'algorithmes de traitement d’images : les méthodes par patchs. Ces méthodes nécessitent une étape appelée agrégation, qui consiste à reformer une image à partir d'un ensemble de patchs, et de modèles statistiques sur ces mêmes patchs. L’étape d'agrégation est formalisée ici comme une opération de fusion de distributions vivant sur des espaces différents mais non-disjoints. On propose d’abord une méthode de fusion basée sur des considérations probabilistes, directement applicable au problème d'agrégation. Il se trouve que cette opération peut aussi se formuler dans un contexte plus général comme une généralisation d'un problème de barycentre entre distributions, ce qui amène à l'étudier dans un deuxième temps du point de vue du transport optimal

Samarium Diiodide medicated cascade radical Cyclisations of Methylenecyclopropane derivatives Synthesis of Bioyclo-(3.2.1.)- Oct

Chapter 2 describes the nucleophilic addition of lithiated methylenecyclopropane to epoxides and studies towards synthesis of keto-alcohol derivatives of methylenecyclopropane such as 189. (Fig. 3929A)Chapter 3 details the of samarium diiodide mediated cascade cyclisation of methylenecyclopropyl methyl ketones 285 and 327. Bicyclic compounds 305 and 348 were obtained in reasonable to good yields and good diastereoselectivity. The cyclisations of these precursors were found to be stereoselective due to chelation control with the samarium (III) species. (Fig. 3929B)Chapter 4 concentrates on the synthesis of phenyl ketone derivatives of methylenecyclopropane 351 and 352 and their cyclisation, which failed to give bicyclo-octanes 353 and 354. (Fig. 3929C)Chapter 5 presents the synthesis and samarium diiodide mediated radical cyclisations of cyclic ketone derivatives of methylenecyclopropane 400 towards tricyclic compounds 401. (Fig. 3929D)</p

A unified view on patch aggregation

International audiencePatch-based methods are widely used in various topics of image processing, such as image restoration or image editing and synthesis. Patches capture local image geometry and structure and are much easier to model than whole images: in practice, patches are small enough to be represented by simple multivariate priors. An important question arising in all patch-based methods is the one of patch aggregation. For instance, in image restoration, restored patches are usually not compatible, in the sense that two overlapping restored patches do not necessarily yield the same values to their common pixels. A standard way to overcome this difficulty is to see the values provided by different patches at a given pixel as independent estimators of a true unknown value and to aggregate these estimators. This aggregation step usually boils down to a simple average , with uniform weights or with weights depending on the trust we have on these different estimators. In this paper, we propose a probabilistic framework aiming at a better understanding of this crucial and often neglected step. The key idea is to see the aggregation of two patches as a fusion between their models rather than a fusion of estimators. The proposed fusion operation is pretty intuitive and generalizes previous aggregation methods. It also yields a novel interpretation of the Expected Patch Log Likelihood (EPLL) proposed in [40

The phospha-Michael addition in organic synthesis

International audienc

Контроль поведения веществ при высоких давлениях и температурах методом гиперспектральной акустооптической спектрометрии : диссертация на соискание ученой степени кандидата технических наук : спец. 05.11.13

We have discovered that alpha-dimethyl(thexyl)silyl]acetaldehyde (= [dimethyl(1,1,2-trimethylpropyl)silyl]acetaldchyde; 31) has a strong, woody odor. Structural analysis has shown resemblance to known odorants with similar organoleptic properties. On the basis of structure-odor relationships, new and more-powerful woody and ambery sila odorants were prepared. Further derivatization led to a set of compounds with very interesting organoleptic properties. Selected chiral compounds were also prepared stereoselectively. The influence of the absolute configuration on the olfactory properties was in agreement with theoretical assumptions. We also designed other groups of organosilicon odorants. The compounds discovered can be obtained in a few simple steps from commercially available reagents, and may find application in the fragrance and flavor industry. Their structures provide interesting data for further research on structure-odor relationships