Cette thèse a pour objectif l’étude de trois problèmes : l’estimation de cartes de saillance de l’énergie du bruit apériodique de la marche humaine par la perception de profondeur pour la détection de pathologies, les modèles de détection d’objets saillants en général et les modèles légers en particulier par l’opposition de couleurs. Comme première contribution, nous proposons un système basé sur une caméra de profondeur et un tapis roulant, qui analyse les parties du corps du patient ayant un mouvement irrégulier, en termes de périodicité, pendant la marche. Nous supposons que la marche d'un sujet sain présente n'importe où dans son corps, pendant les cycles de marche, un signal de profondeur avec un motif périodique sans bruit. La présence de bruit et son importance peuvent être utilisées pour signaler la présence et l'étendue de pathologies chez le sujet. Notre système estime, à partir de chaque séquence vidéo, une carte couleur de saillance montrant les zones de fortes irrégularités de marche, en termes de périodicité, appelées énergie de bruit apériodique, de chaque sujet. Notre système permet aussi de détecter automatiquement les cartes des individus sains et ceux malades. Nous présentons ensuite deux approches pour la détection d’objets saillants. Bien qu’ayant fait l’objet de plusieurs travaux de recherche, la détection d'objets saillants reste un défi. La plupart des modèles traitent la couleur et la texture séparément et les considèrent donc implicitement comme des caractéristiques indépendantes, à tort. Comme deuxième contribution, nous proposons une nouvelle stratégie, à travers un modèle simple, presque sans paramètres internes, générant une carte de saillance robuste pour une image naturelle. Cette stratégie consiste à intégrer la couleur dans les motifs de texture pour caractériser une micro-texture colorée, ceci grâce au motif ternaire local (LTP) (descripteur de texture simple mais puissant) appliqué aux paires de couleurs. La dissemblance entre chaque paire de micro-textures colorées est calculée en tenant compte de la non-linéarité des micro-textures colorées et en préservant leurs distances, donnant une carte de saillance intermédiaire pour chaque espace de couleur. La carte de saillance finale est leur combinaison pour avoir des cartes robustes. Le développement des réseaux de neurones profonds a récemment permis des performances élevées. Cependant, il reste un défi de développer des modèles de même performance pour des appareils avec des ressources limitées. Comme troisième contribution, nous proposons une nouvelle approche pour un modèle léger de réseau neuronal profond de détection d'objets saillants, inspiré par les processus de double opposition du cortex visuel primaire, qui lient inextricablement la couleur et la forme dans la perception humaine des couleurs. Notre modèle proposé, CoSOV1net, est entraîné à partir de zéro, sans utiliser de ``backbones'' de classification d'images ou d'autres tâches. Les expériences sur les ensembles de données les plus utilisés et les plus complexes pour la détection d'objets saillants montrent que CoSOV1Net atteint des performances compétitives avec des modèles de l’état-de-l’art, tout en étant un modèle léger de détection d'objets saillants et pouvant être adapté aux environnements mobiles et aux appareils à ressources limitées. / The purpose of this thesis is to study three problems: the estimation of saliency maps of the aperiodic noise energy of human gait using depth perception for pathology detection, and to study models for salient objects detection in general and lightweight models in particular by color opposition. As our first contribution, we propose a system based on a depth camera and a treadmill, which analyzes the parts of the patient's body with irregular movement, in terms of periodicity, during walking. We assume that a healthy subject gait presents anywhere in his (her) body, during gait cycles, a depth signal with a periodic pattern without noise. The presence of noise and its importance can be used to point out presence and extent of the subject’s pathologies. Our system estimates, from each video sequence, a saliency map showing the areas of strong gait irregularities, in terms of periodicity, called aperiodic noise energy, of each subject. Our system also makes it possible to automatically detect the saliency map of healthy and sick subjects. We then present two approaches for salient objects detection. Although having been the subject of many research works, salient objects detection remains a challenge. Most models treat color and texture separately and therefore implicitly consider them as independent feature, erroneously. As a second contribution, we propose a new strategy through a simple model, almost without internal parameters, generating a robust saliency map for a natural image. This strategy consists in integrating color in texture patterns to characterize a colored micro-texture thanks to the local ternary pattern (LTP) (simple but powerful texture descriptor) applied to the color pairs. The dissimilarity between each colored micro-textures pair is computed considering non-linearity from colored micro-textures and preserving their distances. This gives an intermediate saliency map for each color space. The final saliency map is their combination to have robust saliency map. The development of deep neural networks has recently enabled high performance. However, it remains a challenge to develop models of the same performance for devices with limited resources. As a third contribution, we propose a new approach for a lightweight salient objects detection deep neural network model, inspired by the double opponent process in the primary visual cortex, which inextricably links color and shape in human color perception. Our proposed model, namely CoSOV1net, is trained from scratch, without using any image classification backbones or other tasks. Experiments on the most used and challenging datasets for salient objects detection show that CoSOV1Net achieves competitive performance with state-of-the-art models, yet it is a lightweight detection model and it is a salient objects detection that can be adapted to mobile environments and resource-constrained devices.

My objective with this thesis is to understand how racist stereotypes and myths compounded the sale of fair-skinned black women during and after the slave trade in New Orleans, Louisiana. This commodification of black women's bodies continued well into the twentieth century, notably in New Orleans' vice district of Storyville. Called "quadroons" (a person with ¼ African ancestry) and "octoroons" (1/8 African ancestry), these women were known for their "sexual prowess" and drew in a large number of patrons. The existence of "white passing" black women complicated ideas about race and racial purity in the South. Race as a myth and social construct, or as Evelyn Brooks Higginbotham explains in her essay, African-American Women's History and the Metalanguage of Race, a "metalanguage" exposes race not as a genetic fact, but rather a physical appearance through which power relations and status were to be conferred. My methodology uses race and gender theory to analyze primary and secondary sources to understand and contextualize how population demographics, myths, and liberal 18th century colonial laws contributed to the sale of black women's bodies. The works of Emily Clark, Walter Johnson, Gwendolyn Midlo Hall and other historians who utilize Atlantic history have been paramount in my research. Emily Clark has transformed the "white-black" women from a tragic, sexualized trope into a fully actualized human being, while Hall has tackled the racist underpinnings inherent in the neglect of black women's history. The writings of bell hooks, particularly her essay Eating the Other, establishes the modern day commodification of black women vis-à -vis their representation in media, as well as through the fetishism of their bodies by a white patriarchal system. During slavery plantation owners could do virtually anything they wanted with their property, including engaging in sexual intercourse. By depicting black women as hypersexual jezebels, they could justify their rape, while establishing their dominance and place in the white male hegemony of that time period. For the right price a white male of a lesser class could achieve the same thing at a brothel down in Storyville at the turn of the twentieth century, for as Emily Clark argues in her book, The Strange History of the American Quadroon, these brothels were a great equalizer, allowing all white men to experience "…sexual mastery enjoyed only by elite planters before the Civil War." By democratizing white supremacy, the quadroon and others like her forged solidarity that bridge across all classes, while upholding whiteness and oppressing people of color at the same time.

Bruhn (2008) and Griffiths (1978) have referred in passing to Messiaen's use of non-Western content as an appropriation, but a consideration of its potential moral and aesthetic failings within the scope of modern literature on artistic cultural appropriation is an underexplored topic. Messiaen's first encounter with India came during his student years, by way of a Sanskrit version of Saṅgītaratnākara (c. 1240 CE) written by the thirteenth-century Hindu musicologist Śārṅgadeva. I examine Messiaen's use of Indian deśītālas within a cultural appropriation context. Non-Western music provided a safe space for him to explore the familiar, and served as validation for previously held creative interests, prompting the expansion and development of rhythmic techniques from the unfamiliar. Chapter 1 examines the different forms of artistic cultural appropriation, drawing on the ideas of James O. Young and Conrad G. Brunk (2012) and Bruce H. Ziff and Pratima V. Rao (1997). I consider the impact of power dynamic inequality between 'insider' and 'outsider' cultures. I evaluate the relation between aesthetic errors and authenticity. Chapter 2 considers the internal and external factors and that prompted Messiaen to draw on non-Western rhythm. I examine Messiaen's appropriation of Indian rhythm in relation to Bloomian poetic misreading, and whether his appropriation of Indian rhythm reveals an authentic intention. Chapter 3 analyses Messiaen's interpretation of Śārṅgadeva's 120 deśītālas and its underlying Hindu symbolism. Chapter 4 contextualises Messiaen's Japanese poem Sept haïkaï (1962) in relation to other European Orientalist artworks of the late-nineteenth and early-twentieth centuries, and also in relation to Michael Sullivan's (1987: 209) three-tiered definitions of japonism.