Dissertations / Theses: 'Vision; Point of view'

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Israel, Lana. "Memory perspective and recollective experience." Thesis, University of Oxford, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.365442.

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Diskin, Yakov. "Dense 3D Point Cloud Representation of a Scene Using Uncalibrated Monocular Vision." University of Dayton / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1366386933.

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Alturki, Abdulrahman S. "Principal Point Determination for Camera Calibration." University of Dayton / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1500326474390507.

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Graehling, Quinn R. "Feature Extraction Based Iterative Closest Point Registration for Large Scale Aerial LiDAR Point Clouds." University of Dayton / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1607380713807017.

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Roesler, Axel. "A new model for perspective the role of point of observation in virtual and remote perspective-taking /." Columbus, Ohio : Ohio State University, 2005. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1133297173.

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Stein, Madeleine. "Improving Image Based Fruitcount Estimates Using Multiple View-Points." Thesis, Linköpings universitet, Datorseende, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-132402.

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This master-thesis presents an approach to track and count the number of fruit incommercial mango orchards. The algorithm is intended to enable precision agri-culture and to facilitate labour and post-harvest storage planning. The primary objective is to develop an multi-view algorithm and investigate how it can beused to mitigate the effects of visual occlusion, to improve upon estimates frommethods that use a single central or two opposite viewpoints. Fruit are detectedin images by using two classification methods: dense pixel-wise cnn and regionbased r-cnn detection. Pair-wise fruit correspondences are established between images by using geometry provided by navigation data, and lidar data is used to generate image masks for each separate tree, to isolate fruit counts to individual trees. The tracked fruit are triangulated to locate them in 3D space, and spatial statistics are calculated over whole orchard blocks. The estimated tree counts are compared to single view estimates and validated against ground truth data of 16 mango trees from a Bundaberg mango orchard in Queensland, Australia. The results show a high R2-value of 0.99335 for four hand labelled trees and a highest R2-value of 0.9165 for the machine labelled images using the r-cnn classifier forthe 16 target trees.

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Feydt, Austin Pack. "A Higher-Fidelity Approach to Bridging the Simulation-Reality Gap for 3-D Object Classification." Case Western Reserve University School of Graduate Studies / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=case1558355175360648.

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Bharadwaj, Akshay S. "A Perception Payload for Small-UAS Navigation in Structured Environments." Ohio University / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1533649419108963.

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Fu, Wenhao. "Visual servoing for mobile robots navigation with collision avoidance and field-of-view constraints." Thesis, Evry-Val d'Essonne, 2014. http://www.theses.fr/2014EVRY0019/document.

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Cette thèse porte sur le problème de la navigation basée sur la vision pour les robots mobiles dans les environnements intérieurs. Plus récemment, de nombreux travaux ont été réalisés pour résoudre la navigation à l'aide d'un chemin visuel, à savoir la navigation basée sur l'apparence. Cependant, en utilisant ce schéma, le mouvement du robot est limité au chemin visuel d'entrainement. Le risque de collision pendant le processus de navigation peut faire écarter le robot de la trajectoire visuelle courante, pour laquelle les repères visuels peuvent être perdus. Dans l'état de nos connaissances, les travaux envisagent rarement l'évitement des collisions et la perte de repère dans le cadre de la navigation basée sur l'apparence. Nous présentons un cadre mobile de navigation pour le robot afin de renforcer la capacité de la méthode basée sur l'apparence, notamment en cas d'évitement de collision et de contraintes de champ de vision. Notre cadre introduit plusieurs contributions techniques. Tout d'abord, les contraintes de mouvement sont considérés dans la détection de repère visuel pour améliorer la performance de détection. Ensuite, nous modélisons l'obstacle en utilisant B-Spline. La représentation de B-Spline n'a pas de régions accidentées et peut générer un mouvement fluide pour la tâche d'évitement de collision. En outre, nous proposons une stratégie de contrôle basée sur la vision, qui peut gérer la perte complète de la cible. Enfin, nous utilisons l'image sphérique pour traiter le cas des projections d'ambiguité et d'infini dus à la projection en perspective. Les véritables expériences démontrent la faisabilité et l'efficacité de notre cadre et de nos méthodes
This thesis is concerned with the problem of vision-based navigation for mobile robots in indoor environments. Many works have been carried out to solve the navigation using a visual path, namely appearance-based navigation. However, using this scheme, the robot motion is limited to the trained visual path. The potential collision during the navigation process can make robot deviate from the current visual path, in which the visual landmarks can be lost in the current field of view. To the best of our knowledge, seldom works consider collision avoidance and landmark loss in the framework of appearance-based navigation. We outline a mobile robot navigation framework in order to enhance the capability of appearance-based method, especially in case of collision avoidance and field-of-view constraints. Our framework introduces several technical contributions. First of all, the motion constraints are considered into the visual landmark detection to improve the detection performance. Next then, we model the obstacle boundary using B-Spline. The B-Spline representation has no accidented regions and can generate a smooth motion for the collision avoidance task. Additionally, we propose a vision-based control strategy, which can deal with the complete target loss. Finally, we use spherical image to handle the case of ambiguity and infinity projections due to perspective projection. The real experiments demonstrate the feasability and the effectiveness of our framework and methods

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Aganj, Ehsan. "Multi-view Reconstruction and Texturing=Reconstruction multi-vues et texturation." Phd thesis, Ecole des Ponts ParisTech, 2009. http://pastel.archives-ouvertes.fr/pastel-00517742.

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Dans cette thèse, nous étudions les problèmes de reconstruction statique et dynamique à partir de vues multiples et texturation, en s'appuyant sur des applications réelles et pratiques. Nous proposons trois méthodes de reconstruction destinées à l'estimation d'une représentation d'une scène statique/dynamique à partir d'un ensemble d'images/vidéos. Nous considérons ensuite le problème de texturation multi-vues en se concentrant sur la qualité visuelle de rendu..

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Dagonneau, Virginie. "Etude des liens entre immersion et présence pour la mise au point d'un simulateur de conduite de deux-roues motorisé." Phd thesis, Université Paris Sud - Paris XI, 2012. http://tel.archives-ouvertes.fr/tel-00766116.

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Les environnements virtuels, et en particulier les simulateurs de conduite à plate-forme dynamique, posent la délicate question de la restitution multisensorielle en vue de générer la bonne "illusion" pour leurs utilisateurs. Si la réalité virtuelle est reconnue pour la limitation des coûts, le gain temporel et la contrôlabilité et reproductibilité des situations étudiées, la problématique de la validité de ces outils de recherche (ou de formation) est cruciale pour la transférabilité des connaissances produites.Constituant une première étape dans le processus de validation du simulateur IFSTTAR, ce travail s'appuie sur une démarche originale reposant sur une double évaluation, par élément et globale. Il s'agit (i) de configurer de manière optimale les caractéristiques immersives et interactives du simulateur liées au mouvement de roulis afin de produire une illusion d'inclinaison crédible et acceptée, et (ii) d'évaluer, de manière globale, différentes configurations du simulateur (modèles dynamiques de véhicule) au moyen de mesures objectives (temps de familiarisation) et subjectives (présence, mal du simulateur).Prises dans leur ensemble, les sept études menées durant cette thèse ont permis de valider une plage de restitution du mouvement de roulis pertinente pour produire une sensation d'inclinaison sans entraîner de déséquilibre critique ou de sensation de chute. Un angle d'inclinaison du simulateur au-delà de 11,4 degrés est ainsi déconseillé pour éviter toute sensation de chute, néanmoins cette valeur est susceptible d'être influencée par divers facteurs (e.g., présence d'informations visuelles, positionnement de l'axe de roulis). Ces études ont également permis d'identifier, en conduite passive, les paramètres nécessaires ainsi que les contributions relatives des informations visuelle et inertielle pour la production d'une sensation d'inclinaison crédible. En conduite active, l'évaluation du degré de contrôle des participants en fonction du modèle dynamique de véhicule (virtuel) a permis de pointer les faiblesses actuelles du simulateur IFSTTAR afin de proposer plusieurs pistes de développement.

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Béliveau, Isabelle. "La focalisation : étude théorique de la focalisation et analyse d'Une saison dans la vie d'Emmanuel de Marie-Claire Blais." Mémoire, Université de Sherbrooke, 1995. http://hdl.handle.net/11143/10022.

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Ce mémoire a essentiellement pour objectif de mettre en relief l'importance de la focalisation tant sous son aspect théorique que sur son utilisation dans les romans. Or, je me suis proposée de circonscrire quelques romanciers, théoriciens et critiques qui ont discuté de l'aspect du "point de vue" ou de la focalisation. Dans un premier temps, j'ai illustré par des exemples les types de focalisation (zéro ou omnisciente, interne, externe) qui ont prévalu à certaines époques. En conséquence, les exemples démontrent qu'il y a eu des changements dans la façon dont les narrateurs s'y sont pris pour faire voir leur histoire. Avec les années, l’omniscience s'est faite plus rare au bénéfice des restrictions de champ. Le code modal a changé. Dans un deuxième temps, j'ai couvert chronologiquement en les résumant un certain nombre de concepts et de théories de la focalisation émis par les Anglais, les Allemands, les Américains, les Français et les Hollandais. J'ai également noté quelques conflits entre ceux-ci. Les théories et concepts s'étalent sur un peu moins d'un siècle, soit de 1898 avec Henry James jusqu'en 1981 avec Jaap Lintvelt. Dans un troisième temps, j'ai montré que l'éclosion des théories et des concepts pourrait éventuellement, compte tenu de leur ressemblance de fond, être l'aboutissement d'une seule théorie de la focalisation. Souvent, les mêmes concepts sont répétés, mais dans des termes différents. Cette partie du travail se fit en amont, puisqu'à partir des concepts les plus récents sur la focalisation, j'ai retracé quelques-uns des prédécesseurs sans prétendre toutefois ne pas avoir fait d'omission et sans prétendre non plus être remontée à l'ultime source. Dans un quatrième et dernier temps, me rapportant au roman de Marie-Claire Biais : Une saison dans la vie d'Emmanuel (1965), et inspirée et influencée principalement par Mieke Bal, je me suis arrêtée à examiner les effets implicites que les types de vision ou de focalisation et les rapports entre "objet" focalisé et sujet focalisateur peuvent avoir sur le processus de lecture et le cadre de réception. J'ai tenté d'éclairer la forme cachée de la structure de la focalisation et montrer qu'elle peut être une entrée pertinente pour l'étude d'un roman.

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Mougenel-Chantereau, Robert. "Faille fragile : questionnement poïétique de l'ouvert dans les arts visuels." Thesis, Paris 1, 2013. http://www.theses.fr/2013PA010687.

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Comment créer une œuvre picturale qui pourrait s'animer? A partir du jeu de cache-cache de la vidéo "Augenblick", l'analyse poïétique de la sculpture OUI-NON de Markus Raetz confrontée aux peintures du Retable de Genève de Konrad Witz révèle une surprenante logique d'animation, Les procès de création de ce retable du 15e siècle déterminent l'actualisation de visions dynamiques dans ce type de construction picturale, également rencontré chez Lorenzo Veneziano, Henri Bellechose, Filippo Lippi ou Sandro Botticelli et dans différents édifices médiévaux. Ainsi, des éléments picturaux souvent considérés comme archaïques participent d'un système poïétique dynamique raisonné proposant des animations significatives au cours d'une vision active autrement dit, d'un déplacement du regard. Le concept plus global de vision à point de vue dynamique étend la réflexion à différents modes de déplacements du point de vue. La vidéo permet une forme d’objectivation des enchainements d'images de ce type de construction picturale vis-à-vis de dispositifs déterminés par ces peintures. Ces tentatives d'objectivation fonctionnent sur un plan didactique mais n'engagent pas un partage sensible en interaction avec l'image. Cette perte de l'interaction dans les films engage une réflexion sur l’indissociabilité du couple faille-fragile qui retrouve une possibilité oubliée d'interaction active avec une image fixe. En dehors de toute dissociation artificielle d'une perception et de son mouvement pour regarder une œuvre, cette interaction engage le questionnement poïétique de l'ouvert par différentes installations et performances
How to create a painting which could animate itself ? Starting from the game of hide and seek in the Augenblick video, a poietic analysis of the OUI-NON sculpture by Markus Raetz, confronted with Konrad Witz's paintings of the Geneva altarpiece, reveals an animation logic. The creation process of 15th century reredos determines the actualization of dynamic visions in this type of pictural construction that is also found in works of Lorenzo Veneziano, Henri Bellechose, Filippo Lippi and Sandro Botticelli as well as in medieval edifices. Thus, some pictorial elements often considered (until the end of the 20th century) as archaic, integrate a reasoned dynamic poietic system offering effective animation during an active vision, that is, the displacement of the viewer during the observation. The broader concept of vision with a dynamic point of view widens the analysis to different modes of displacement of the point of view. Video allows for a form of objectification of the sequences perceived in such pictorial constructions through devices determined by these paintings. These objectification attempts succeed on a didactic level, but fail to engage a sensitive perception though interaction with the image. This loss of interaction in the filmed sequences forces thinking about the inseparability of the "faille - fragile" couple which recovers a long lost possibility tor an active interaction with a still image. Without any artificial dissociation of the perception and the associated movement tor looking at a work, this interaction engages poietic questioning of the open through various installations and performances

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Treaster, Delia E. "An investigation of postural and visual stressors and their interactions during computer work." Connect to this title online, 2003. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1055885997.

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Thesis (Ph. D.)--Ohio State University, 2003.
Title from first page of PDF file. Document formatted into pages; contains xvii, 211 p.: ill. (some col.). Includes abstract and vita. Advisor: William S. Marras, Dept. of Industrial, Welding, and Systems Engineering. Includes bibliographical references (p. 177-206).

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Hallenberg, Johan. "Robot Tool Center Point Calibration using Computer Vision." Thesis, Linköping University, Department of Electrical Engineering, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-9520.

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Today, tool center point calibration is mostly done by a manual procedure. The method is very time consuming and the result may vary due to how skilled the operators are.

This thesis proposes a new automated iterative method for tool center point calibration of industrial robots, by making use of computer vision and image processing techniques. The new method has several advantages over the manual calibration method. Experimental verifications have shown that the proposed method is much faster, still delivering a comparable or even better accuracy. The setup of the proposed method is very easy, only one USB camera connected to a laptop computer is needed and no contact with the robot tool is necessary during the calibration procedure.

The method can be split into three different parts. Initially, the transformation between the robot wrist and the tool is determined by solving a closed loop of homogeneous transformations. Second an image segmentation procedure is described for finding point correspondences on a rotation symmetric robot tool. The image segmentation part is necessary for performing a measurement with six degrees of freedom of the camera to tool transformation. The last part of the proposed method is an iterative procedure which automates an ordinary four point tool center point calibration algorithm. The iterative procedure ensures that the accuracy of the tool center point calibration only depends on the accuracy of the camera when registering a movement between two positions.

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Saravi, Sara. "Use of Coherent Point Drift in computer vision applications." Thesis, Loughborough University, 2013. https://dspace.lboro.ac.uk/2134/12548.

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This thesis presents the novel use of Coherent Point Drift in improving the robustness of a number of computer vision applications. CPD approach includes two methods for registering two images - rigid and non-rigid point set approaches which are based on the transformation model used. The key characteristic of a rigid transformation is that the distance between points is preserved, which means it can be used in the presence of translation, rotation, and scaling. Non-rigid transformations - or affine transforms - provide the opportunity of registering under non-uniform scaling and skew. The idea is to move one point set coherently to align with the second point set. The CPD method finds both the non-rigid transformation and the correspondence distance between two point sets at the same time without having to use a-priori declaration of the transformation model used. The first part of this thesis is focused on speaker identification in video conferencing. A real-time, audio-coupled video based approach is presented, which focuses more on the video analysis side, rather than the audio analysis that is known to be prone to errors. CPD is effectively utilised for lip movement detection and a temporal face detection approach is used to minimise false positives if face detection algorithm fails to perform. The second part of the thesis is focused on multi-exposure and multi-focus image fusion with compensation for camera shake. Scale Invariant Feature Transforms (SIFT) are first used to detect keypoints in images being fused. Subsequently this point set is reduced to remove outliers, using RANSAC (RANdom Sample Consensus) and finally the point sets are registered using CPD with non-rigid transformations. The registered images are then fused with a Contourlet based image fusion algorithm that makes use of a novel alpha blending and filtering technique to minimise artefacts. The thesis evaluates the performance of the algorithm in comparison to a number of state-of-the-art approaches, including the key commercial products available in the market at present, showing significantly improved subjective quality in the fused images. The final part of the thesis presents a novel approach to Vehicle Make & Model Recognition in CCTV video footage. CPD is used to effectively remove skew of vehicles detected as CCTV cameras are not specifically configured for the VMMR task and may capture vehicles at different approaching angles. A LESH (Local Energy Shape Histogram) feature based approach is used for vehicle make and model recognition with the novelty that temporal processing is used to improve reliability. A number of further algorithms are used to maximise the reliability of the final outcome. Experimental results are provided to prove that the proposed system demonstrates an accuracy in excess of 95% when tested on real CCTV footage with no prior camera calibration.

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McKeehan, Zachary D. "Vision-based interest point extraction evaluation in multiple environments." Thesis, Monterey, Calif. : Naval Postgraduate School, 2008. http://edocs.nps.edu/npspubs/scholarly/theses/2008/Sept/08Sep%5FMcKeehan.pdf.

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Thesis (M.S. in Computer Science)--Naval Postgraduate School, September 2008.
Thesis Advisor(s): Kolsch, Mathias ; Squire, Kevin. "September 2008." Description based on title screen as viewed on November 3, 2008. Includes bibliographical references (p. 175-181). Also available in print.

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Sze, Wui-fung. "Robust feature-point based image matching." Click to view the E-thesis via HKUTO, 2006. http://sunzi.lib.hku.hk/hkuto/record/B37153262.

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Chavez, Aaron J. "A fast interest point detection algorithm." Thesis, Manhattan, Kan. : Kansas State University, 2008. http://hdl.handle.net/2097/538.

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Sze, Wui-fung, and 施會豐. "Robust feature-point based image matching." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2006. http://hub.hku.hk/bib/B37153262.

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Berggrén, Rasmus. "In pursuit of consumer-accessible augmented virtuality." Thesis, KTH, Skolan för datavetenskap och kommunikation (CSC), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-209548.

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This project is an examination of the possibility of using existing software to develop Virtual Reality (VR) software that includes key aspects of objects in a user’s surroundings into a virtual environment, producing Augmented Virtuality (AV). A defining limitation is the requirement that the software be consumer-accessible, meaning it needs run on a common smartphone with no additional equipment. Two related AV concepts were considered: shape reconstruction and positional tracking. Two categories of techniques were considered for taking the measurements of reality necessary to achieve those AV concepts using only a monocular RGB camera as sensor: monocular visual SLAM (mvSLAM) and Structure from Motion (SfM). Two lists of requirements were constructed, formalising the notions of AV and consumer-accessibility. A search process was then conducted, where existing software packages were evaluated for their suitability to be included in a piece of software fulfilling all requirements. The evaluations of SfM systems were made in combination with Multi-View Stereo (MVS) systems – a necessary complement for achieving visible shape reconstruction using a system that outputs point clouds. After thoroughly evaluating a variety of software, it was concluded that consumer-accessible AV can not currently be achieved by combining existing packages, due to several issues. While future hardware performance increases and new software implementations would solve complexity and availability issues, some inaccuracy and usability issues are inherent to the limitation of using a monocular camera.
Detta projekt är en undersökning av möjligheten att använda befintlig programvara till att utveckla Virtual Reality (VR)-programvara som infogar framstående aspekter av objekt från en användares omgivning in i en virtuell miljö och därmed skapar Augmented Virtuality (AV). En definierande begränsning är kravet på att programvaran skall vara konsumenttillgänglig, vilket innebär att den behöver kunna köras på en vanlig smartphone utan extra utrustning. Två besläktade AV-koncept beaktades: formrekonstruktion och positionsspårning. Två kategorier av tekniker togs i beaktande, vilka kunde användas för att göra de uppmätningar av verkligheten som var nödvändiga för att uppnå de tänkta AV-koncepten med hjälp av endast en monokulär RGB-kamera som sensor: monocular visual SLAM (mvSLAM) och Structure from Motion (SfM). Två listor med kriterier konstruerades, vilka formaliserade begreppen AV och konsumenttillgänglighet. En sökprocess utfördes sedan, där befintliga programvarupaket utvärderades för sin lämplighet att inkluderas i en programvara som uppfyllde alla kriterier. Utvärderingarna av SfM-system gjordes i kombination med Multi-View Stereo (MVS)-system – ett nödvändigt komplement för att uppnå synlig formrekonstruktion med ett system vars utdata är punktmoln. Efter att noggrant ha utvärderat en mängd programvara var slutsatsen att konsumenttillgänglig AV inte för närvarande kan uppnås genom att kombinera befintliga programvarupaket, på grund av ett antal olika problem. Medan framtida prestandaökningar hos maskinvara och nya programvarutillämpningar skulle lösa problem med komplexitet och tillgänglighet, är vissa problem med tillförlitlighet och användbarhet inneboende hos begränsningen till att använda en monokulär kamera.

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Faille, Flore. "Illumination invariant interest point detection for vision based recognition tasks." [S.l.] : [s.n.], 2007. http://mediatum2.ub.tum.de/doc/613251/document.pdf.

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Parag, Kris Varun. "Point process noise in fundamental molecular reactions and invertebrate vision." Thesis, University of Cambridge, 2014. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.708246.

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Athari, Nikazm Marzieh. "Vision, passion, point de vue : un modèle sémiotique chez Paul Valéry." Phd thesis, Université Paris VIII Vincennes-Saint Denis, 2006. http://tel.archives-ouvertes.fr/tel-00181005.

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Cette étude interroge le problème de la vision dans l'œuvre de Paul Valéry. La vision s'articule avec la question de l'énonciation où l'apparition du système "Moi" s'affine dans une structure dynamique qui engage une pluralité d'instances. Énonciation, perception et vision sont donc liées. Cette dernière, d'ordre pragmatique, se décline en une typologie de regards ; mais elle est aussi d'ordre passionnel avec la figure centrale de "Narcisse" dans l'œuvre valéryenne. Le parcours de Valéry est appelé quête narcisséenne, dans laquelle le "Moi" est compris comme « à chaque instant cette propriété de juger ». Cette quête anti-narcissique est liée à la question de la récursivité. En effet, la pensée de Valéry peut être comprise comme une interrogation sur cette structure syntaxique où le champ récursif du "moi" est susceptible de se déplacer et de se transformer à l'infini. La construction du point de vue devient l'une des spécificités de l'acte énonciatif. Par le point de vue, Valéry arrive à une nouvelle conception de la vision. Ainsi, à travers la lecture de Valéry, se forme une "sémiotique valéryenne" qui, comme toutes les sémiotiques, repose implicitement ou explicitement sur un modèle perceptif et sur une théorie de la connaissance.

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White, Raymond Gordon. "Effect of point-spread functions on geometric measurements in computer vision." Diss., The University of Arizona, 1991. http://hdl.handle.net/10150/185463.

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The point-spread function (PSF) of an imaging system can affect the precision to which geometric features can be measured in digital images. It is shown that the PSF alone, when larger than a certain size relative to the sampling rate, does not cause a loss of precision, but actually improves the precision to which features can be measured. Quantization of the samples in an image is the limiting factor on precision. How much the precision is limited in the face of quantization depends on the size and shape of the PSF. The theory of locales is used extensively to compute bounds on precision as a function of PSF size and shape. Many geometric feature models are considered although almost all of the emphasis is on analysis of the unit step edge. It is shown for the step edge that the size of a PSF has more influence on precision than its shape. The size for which optimal precision occurs is ∼0.7 pixels in "radius". Bounds on precision are also shown for the case of a fixed rectangular sampling PSF with a variable-sized optical PSF and for the case where electronic components introduce asymmetry into the PSF. A method for objective comparison of imaging system PSFs is demonstrated. Other factors influencing precision, including unknown scene contrast and noise, are briefly examined. To illustrate the utility of the results, an experiment is presented showing that approximation of a PSF by a Gaussian PSF results in little loss of precision. Another illustrative experiment shows how the orientation precision of several widely-used first derivative operators are affected by the PSF and shows how the template coefficients can be found to optimize orientation precision for a given PSF.

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Athari, Nikazm Marzieh Bertrand Denis. "Vision, passion, point de vue un modèle sémiotique chez Paul Valéry /." Saint-Denis : Université de Paris 8, 2007. http://www.bu.univ-paris8.fr/consult.php?url_these=theses/AthariThese.pdf.

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Izatt, Gregory (Gregory Russell). "Robust object pose estimation with point clouds from vision and touch." Thesis, Massachusetts Institute of Technology, 2017. http://hdl.handle.net/1721.1/111867.

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Thesis: S.M., Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science, 2017.
This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Cataloged from student-submitted PDF version of thesis.
Includes bibliographical references (pages 75-81).
We present a study of object pose estimation performed with hybrid visuo-tactile sensing in mind. We propose that a tactile sensor can be treated as a source of dense local geometric information, and hence consider it to be a point cloud source analogous to an RGB-D camera. We incorporate the tactile geometric information directly into a conventional point-cloud-based articulated object tracker based on signed-distance functions. This tracker runs at 12 Hz using an online depth reconstruction algorithm for the GelSight tactile sensor and a modified second-order update for the tracking algorithm. The tracker provides robust pose estimates of small objects throughout manipulation, even when the objects are occluded by the robot's end effector. To address limitations in this tracker, we additionally present a formulation of the underlying point-cloud correspondence problem as a mixed-integer convex program, which we efficiently solve to optimality with an off-the-shelf branch and bound solver. We show that reasoning about object pose estimation in this way allows natural extension to point-to-mesh correspondence, multiple object estimation, and outlier rejection without losing the ability to obtain a globally optimal solution. We probe the extent to which rich problem-specific formulations typically tackled with unreliable nonlinear optimization can be rigorously treated in a global optimization framework.
by Gregory Izatt.
S.M.

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Herrera, Castro D. (Daniel). "From images to point clouds:practical considerations for three-dimensional computer vision." Doctoral thesis, Oulun yliopisto, 2015. http://urn.fi/urn:isbn:9789526208534.

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Abstract Three-dimensional scene reconstruction has been an important area of research for many decades. It has a myriad of applications ranging from entertainment to medicine. This thesis explores the 3D reconstruction pipeline and proposes novel methods to improve many of the steps necessary to achieve a high quality reconstruction. It proposes novel methods in the areas of depth sensor calibration, simultaneous localization and mapping, depth map inpainting, point cloud simplification, and free-viewpoint rendering. Geometric camera calibration is necessary in every 3D reconstruction pipeline. This thesis focuses on the calibration of depth sensors. It presents a review of sensors models and how they can be calibrated. It then examines the case of the well-known Kinect sensor and proposes a novel calibration method using only planar targets. Reconstructing a scene using only color cameras entails di_erent challenges than when using depth sensors. Moreover, online applications require real-time response and must update the model as new frames are received. The thesis looks at these challenges and presents a novel simultaneous localization and mapping system using only color cameras. It adaptively triangulates points based on the detected baseline while still utilizing non-triangulated features for pose estimation. The thesis addresses the extrapolating missing information in depth maps. It presents three novel methods for depth map inpainting. The first utilizes random sampling to fit planes in the missing regions. The second method utilizes a 2nd-order prior aligned with intensity edges. The third method learns natural filters to apply a Markov random field on a joint intensity and depth prior. This thesis also looks at the issue of reducing the quantity of 3D information to a manageable size. It looks at how to merge depth maps from multiple views without storing redundant information. It presents a method to discard this redundant information while still maintaining the naturally variable resolution. Finally, transparency estimation is examined in the context of free-viewpoint rendering. A procedure to estimate transparency maps for the foreground layers of a multi-view scene is presented. The results obtained reinforce the need for a high accuracy 3D reconstruction pipeline including all the previously presented steps
Tiivistelmä Kolmiuloitteisen ympäristöä kuvaavan mallin rakentaminen on ollut tärkeä tutkimuksen kohde jo usean vuosikymmenen ajan. Sen sovelluskohteet ulottuvat aina lääketieteestä viihdeteollisuuteen. Väitöskirja tarkastelee 3D ympäristöä kuvaavan mallin tuottamisprosessia ja esittää uusia keinoja parantaa korkealaatuisen rekonstruktion tuottamiseen vaadittavia vaiheita. Työssä esitetään uusia menetelmiä etäisyyssensoreiden kalibrointiin, samanaikaisesti tapahtuvaan paikannukseen ja kartoitukseen, syvyyskartan korjaamiseen, etäisyyspistepilven yksinkertaistamiseen ja vapaan katselukulman kuvantamiseen. Väitöskirjan ensi osa keskittyy etäisyyssensoreiden kalibrointiin. Työ esittelee erilaisia sensorimalleja ja niiden kalibrointia. Yleisen tarkastelun lisäksi keskitytään hyvin tunnetun Kinect-sensorin käyttämiseen, ja ehdotetaan uutta kalibrointitapaa pelkkiä tasokohteita hyväksikäyttäen. Pelkkien värikameroiden käyttäminen näkymän rekonstruointiin tuottaa erilaisia haasteita verrattuna etäisyyssensoreiden käyttöön kuvan muodostamisessa. Lisäksi verkkosovellukset vaativat reaaliaikaista vastetta. Väitös tarkastelee kyseisiä haasteita ja esittää uudenlaisen yhtäaikaisen paikannuksen ja kartoituksen mallin tuottamista pelkkiä värikameroita käyttämällä. Esitetty tapa kolmiomittaa adaptiivisesti pisteitä taustan pohjalta samalla kun hyödynnetään eikolmiomitattuja piirteitä asentotietoihin. Työssä esitellään kolme uudenlaista tapaa syvyyskartan korjaamiseen. Ensimmäinen tapa käyttää satunnaispisteitä tasojen kohdentamiseen puuttuvilla alueilla. Toinen tapa käyttää 2nd-order prior kohdistusta ja intensiteettireunoja. Kolmas tapa oppii filttereitä joita se soveltaa Markov satunnaiskenttiin yhteisillä tiheys ja syvyys ennakoinneilla. Tämä väitös selvittää myös mahdollisuuksia 3D-information määrän pienentämiseen käsiteltävälle tasolle. Työssä selvitetään, kuinka syvyyskarttoja voidaan yhdistää ilman päällekkäisen informaation tallentamista. Työssä esitetään tapa jolla päällekkäisestä datasta voidaan luopua kuitenkin säilyttäen luonnollisesti muuttuva resoluutio. Viimeksi, tutkimuksessa on esitetty läpinäkyvyyskarttojen arviointiproseduuri etualan kerroksien monikatselukulmanäkymissä vapaan katselukulman renderöinnin näkökulmasta. Saadut tulokset vahvistavat tarkan 3D-näkymän rakentamisliukuhihnan tarvetta sisältäen kaikki edellä mainitut vaiheet

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Chan, Kap Luk. "Optimization of multiple view stereo vision." Thesis, Imperial College London, 1991. http://hdl.handle.net/10044/1/46705.

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Lee, Kai-wah. "Mesh denoising and feature extraction from point cloud data." Click to view the E-thesis via HKUTO, 2009. http://sunzi.lib.hku.hk/hkuto/record/B42664330.

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Forsman, Mona. "Point cloud densification." Thesis, Umeå universitet, Institutionen för fysik, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-39980.

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Several automatic methods exist for creating 3D point clouds extracted from 2D photos. In manycases, the result is a sparse point cloud, unevenly distributed over the scene.After determining the coordinates of the same point in two images of an object, the 3D positionof that point can be calculated using knowledge of camera data and relative orientation. A model created from a unevenly distributed point clouds may loss detail and precision in thesparse areas. The aim of this thesis is to study methods for densification of point clouds. This thesis contains a literature study over different methods for extracting matched point pairs,and an implementation of Least Square Template Matching (LSTM) with a set of improvementtechniques. The implementation is evaluated on a set of different scenes of various difficulty. LSTM is implemented by working on a dense grid of points in an image and Wallis filtering isused to enhance contrast. The matched point correspondences are evaluated with parameters fromthe optimization in order to keep good matches and discard bad ones. The purpose is to find detailsclose to a plane in the images, or on plane-like surfaces. A set of extensions to LSTM is implemented in the aim of improving the quality of the matchedpoints. The seed points are improved by Transformed Normalized Cross Correlation (TNCC) andMultiple Seed Points (MSP) for the same template, and then tested to see if they converge to thesame result. Wallis filtering is used to increase the contrast in the image. The quality of the extractedpoints are evaluated with respect to correlation with other optimization parameters and comparisonof standard deviation in x- and y- direction. If a point is rejected, the option to try again with a largertemplate size exists, called Adaptive Template Size (ATS).

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Lee, Kai-wah, and 李啟華. "Mesh denoising and feature extraction from point cloud data." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2009. http://hub.hku.hk/bib/B42664330.

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Obergfell, Klaus. "A vision-based end-point control for a two-link flexible manipulator." Thesis, Georgia Institute of Technology, 1991. http://hdl.handle.net/1853/17654.

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Short, Nathaniel Jackson. "3-D Point Cloud Generation from Rigid and Flexible Stereo Vision Systems." Thesis, Virginia Tech, 2009. http://hdl.handle.net/10919/36426.

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When considering the operation of an Unmanned Aerial Vehicle (UAV) or an Unmanned Ground Vehicle (UGV), such problems as landing site estimation or robot path planning become a concern. Deciding if an area of terrain has a level enough slope and a wide enough area to land a Vertical Take Off and Landing (VTOL) UAV or if an area of terrain is traversable by a ground robot is reliant on data gathered from sensors, such as cameras. 3-D models, which can be built from data extracted from digital cameras, can help facilitate decision making for such tasks by providing a virtual model of the surrounding environment the system is in. A stereo vision system utilizes two or more cameras, which capture images of a scene from two or more viewpoints, to create 3-D point clouds. A point cloud is a set of un-gridded 3-D points corresponding to a 2-D image, and is used to build gridded surface models. Designing a stereo system for distant terrain modeling requires an extended baseline, or distance between the two cameras, in order to obtain a reasonable depth resolution. As the width of the baseline increases, so does the flexibility of the system, causing the orientation of the cameras to deviate from their original state. A set of tools have been developed to generate 3-D point clouds from rigid and flexible stereo systems, along with a method for applying corrections to a flexible system to regain distance accuracy in a flexible system.
Master of Science

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Gilson, Stuart J. "Deformable contour methods for shape extraction from binary edge-point images." Thesis, University of Southampton, 1999. https://eprints.soton.ac.uk/256268/.

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Zanchetta, Ferdinando. "Supergeometry: a categorical point of view." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2015. http://amslaurea.unibo.it/9027/.

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In questa tesi viene studiato l'approccio funtoriale alla supergeometria. In particolare si usano le topologie di Grothendieck per studiare il concetto di rappresentabilità in questo contesto, in analogia a quanto fatto in geometria algebrica classica. Vengono poi introdotti i funtori di Weil-Berezin e lo Schwarz embedding, motivando i legami tra questi concetti e la rappresentabilità nel caso classico.

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Shipley, Jeremy Robert. "From a structural point of view." Diss., University of Iowa, 2011. https://ir.uiowa.edu/etd/1178.

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In this thesis I argue forin re structuralism in the philosophy of mathematics. In the first chapters of the thesis I argue that there is a genuine epistemic access problem for Platonism, that the semantic challenge to nominalism may be met by paraphrase strategies, and that nominalizations of scientific theories have had adequate success to blunt the force of the indispensability argument for Platonism. In the second part of the thesis I discuss the development of logicism and structuralism as methodologies in the history of mathematics. The goal of this historical investigation is to lay the groundwork for distinguishing between the philosophical analysis of the content of mathematics and the analysis of the breadth and depth of results in mathematics. My central contention is that the notion of logical structure provides a context for the latter not the former. In turn, this contention leads to a rejection of ante rem structuralism in favor of in re structuralism. In the concluding part of the dissertation the philosophy of mathematical structures developed and defended in the preceding chapters is applied to the philosophy of science.

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Tous, Terrades Francesc. "Computational framework for the white point interpretation based on nameability." Doctoral thesis, Universitat Autònoma de Barcelona, 2006. http://hdl.handle.net/10803/5765.

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En aquest treball presentem un marc per a l'estimació del punt blanc en imatges sota condicions no calibrades, on considerem múltiples solucions interpretades. D'aquesta manera, proposem la utilització d'una cua visual que ha estat relacionada amb la constància de color: aparellament de colors. Aquest aparellament de colors està guiat per la introducció d'informació semàntica referent al contingut de la imatge. Així doncs, introduïm informació d'alt nivell dels colors que esperem trobar en les imatges. Tenint en compte aquestes dues idees, aparellament de colors i informació semàntica, i les aproximacions computacionals a la constància de color existents, proposem un mètode d'estimació de punt blanc per condicions no calibrades que lliura múltiples solucions, en funció de diferents interpretacions dels colors d'una escena. Plantegem l'extracció de múltiples solucions ja que pot permetre extreure més informació de l'escena que els algorismes clàssics de constància de color. En aquest cas, les múltiples solucions venen ponderades pel seu grau d'aparellament dels colors amb la informació semàntica introduïda. Finalment demostrem que la solució plantejada permet reduir el conjunt de solucions possibles a un conjunt més significant, que és petit i fàcilment interpretable.
El nostre estudi està emmarcat en un projecte d'anotació d'imatges que pretén obtenir descriptors que representen la imatge, en concret, els descriptors de la llum de l'escena. Definim dos contextos diferents per aquest projecte: condicions calibrades, quan coneixem alguna informació del sistema d'adquisició, i condicions no calibrades, quan no coneixem res del procés d'adquisició. Si bé ens hem centrat en el cas no calibrat, pel cas calibrat hem proposat també un mètode computacional de constància de color que introdueix l'assumpció de 'món gris' relaxada per a generar un conjunt de solucions possibles més reduït. Aquest mètode té un bon rendiment, similar al dels mètodes existents, i redueix el tamany del conjunt de solucions obtingut.
In this work we present a framework for white point estimation of images under uncalibrated conditions where multiple interpretable solutions can be considered. In this way, we propose to use the colour matching visual cue that has been proved as related to colour constancy. The colour matching process is guided by the introduction of semantic information regarding the image content. Thus, we introduce high-level information of colours we expect to find in the images. Considering these two ideas, colour matching and semantic information, and existing computational colour constancy approaches, we propose a white point estimation method for uncalibrated conditions which delivers multiple solutions according to different interpretations of the colours in a scene. However, we present the selection of multiple solutions which enables to obtain more information of the scene than existing colour constancy methods, which normally select a unique solution. In this case, the multiple solutions are weighted by the degree of colour matching between colours in the image and semantic information introduced. Finally, we prove that the feasible set of solutions can be reduced to a smaller and more significant set with a semantic interpretation.
Our study is framed in a global image annotation project which aims to obtain descriptors which depict the image, in this work we focus on illuminant descriptors.We define two different sets of conditions for this project: (a) calibrated conditions, when we have some information about the acquisition process and (b) uncalibrated conditions, when we do not know the acquisition process. Although we have focused on the uncalibrated case, for calibrated conditions we also propose a colour constancy method which introduces the relaxed grey-world assumption to produce a reduced feasible set of solutions. This method delivers good performance similar to existing methods and reduces the size of the feasible set obtained.

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Hudson, Brenda Kay. "Vision of creation| A Jungian view of Hildegard's "On the Origin of Life" vision." Thesis, Pacifica Graduate Institute, 2015. http://pqdtopen.proquest.com/#viewpdf?dispub=3716788.

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Hildegard von Bingen, a visionary abbess living in the tumultuous 12th century, recorded and interpreted three very powerful visions pertaining to Christianity. This dissertation is limited to the first image of Hildegard’s last vision called De Operatione Dei, the Works of God, a cosmological vision about creation. Hildegard named this image On the Origin of Life.

The thesis of this dissertation suggests the four main characters in the first image of Hildegard’s cosmological vision—the two-headed and four-winged red figure named Caritas standing on the serpent-wrapped monster—correspond to the four stages of Jung’s individuation—encounter with the shadow (serpent), encounter with the soulimage (monster as Adam), encounter with the god-image (Caritas), emergence of the Self (godhead). Each of these characters and stages represent a level in what has been called by perennial philosophy the Great Chain of Being. Hildegard’s vision represents the unfolding of Spirit into matter. Jung’s individuation process describes the soul’s journey back towards Spirit.

This work starts by introducing the vision and Hildegard’s interpretation. Next it moves to what other authors have written. Since the vision is about creation the interpretation starts with the literalists’ view of Genesis and moves to the mystical interpretations of Genesis. Other creation stories including a serpent and a goddess amplify the interpretation. Then, using Jungian and alchemical symbols the images of this iv vision are further elaborated. The research follows the logic of the axiom of Maria, from the uroboros, to the hermaphrodite, to the trinity and ending with the marriage quaternio—two pairs of hermaphrodites. Byington’s symbolic elaboration process is used to interpret the dramatic action of the vision thereby bringing the vision back to life as Hildegard might have experienced it. Finally, the parallel between Hildegard’s vision and Jung’s individuation process is explained in detail. The work ends with Hildegard’s interpretation of why god created the world showing how it aligns with the goal of individuation, and how both are critical for the life of the soul in the 21^st century.

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Runow, Björn. "Deep Learning for Point Detection in Images." Thesis, Linköpings universitet, Datorseende, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-166644.

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The main result of this thesis is a deep learning model named BearNet, which can be trained to detect an arbitrary amount of objects as a set of points. The model is trained using the Weighted Hausdorff distance as loss function. BearNet has been applied and tested on two problems from the industry. These are: From an intensity image, detect two pocket points of an EU-pallet which an autonomous forklift could utilize when determining where to insert its forks. From a depth image, detect the start, bend and end points of a straw attached to a juice package, in order to help determine if the straw has been attached correctly. In the development process of BearNet I took inspiration from the designs of U-Net, UNet++ and a high resolution network named HRNet. Further, I used a dataset containing RGB-images from a surveillance camera located inside a mall, on which the aim was to detect head positions of all pedestrians. In an attempt to reproduce a result from another study, I found that the mall dataset suffers from training set contamination when a model is trained, validated, and tested on it with random sampling. Hence, I propose that the mall dataset is evaluated with a sequential data split strategy, to limit the problem. I found that the BearNet architecture is well suited for both the EU-pallet and straw datasets, and that it can be successfully used on either RGB, intensity or depth images. On the EU-pallet and straw datasets, BearNet consistently produces point estimates within five and six pixels of ground truth, respectively. I also show that the straw dataset only constitutes a small subset of all the challenges that exist in the problem domain related to the attachment of a straw to a juice package, and that one therefore cannot train a robust deep learning model on it. As an example of this, models trained on the straw dataset cannot correctly handle samples in which there is no straw visible.

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Taylor, Benjamin D. "At Which Point." Bowling Green State University / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1300732113.

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Poudel, Pawan. "Computing point-to-point shortest path using an approximate distance oracle." Oxford, Ohio : Miami University, 2008. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=miami1228887237.

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Benkhaled, Imad. "Mise au point d’une chaîne de capture/ restitution stéréoscopique d’images couleurs : application à la conception d’interfaces adaptées aux déficients visuels." Thesis, Montpellier, 2018. http://www.theses.fr/2018MONTS037/document.

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Les travaux de cette thèse sont menés dans le cadre d’un projet porté par le centre de recherche LGI2P, (IMT Mines Ales). L’objectif final de ce projet vise à permettre le retour à l’emploi et à améliorer le quotidien des personnes malvoyantes atteintes de rétinite pigmentaire et de glaucome. Le dispositif final est conçu pour aider les personnes dans leurs activités en mobilité : détection d’obstacles, recherche d’indices visuels, en adressant les problèmes liés à l’éblouissement et à l’héméralopie dont souffrent ces utilisateurs potentiels.La contribution de cette thèse au projet se situe sur plusieurs plans. Tout d’abord, il était demandé de définir les paramètres caractérisant la vision résiduelle de chaque utilisateur. En effet, chaque patient a ses propres conditions de confort lumineux, qui dépendent en particulier de l’état d’avancement de sa pathologie : à chaque étape de l’évolution de leur maladie, les patients ont des limites spécifiques de luminosité minimale en dessous de laquelle ils ne perçoivent plus les détails dans une scène, et aussi de la luminosité maximale au-dessus de laquelle ils ressentent gêne et douleur. La définition de ces limitations en luminosité va permettre de paramétrer le dispositif et l’adapter à chaque utilisateur. Mais il n’existe pas de méthode pour mesurer ces niveaux de luminance limite. Nous avons donc participé à la conception et au développement de tests dédiés, et à la réalisation d’essais sur des sujets déficients visuels, dans le cadre d’un essai clinique piloté par le CHU de Nîmes et l’ARAMAV (institut spécialisé dans la rééducation fonctionnelle basse vision), pour l’aspect médical. Nous avons également proposé un nouveau test pour mesurer la sensibilité au contraste chromatique, toujours dans le but de mieux adapter les images affichées à la vision des utilisateurs.Nous avons ensuite travaillé sur la mise au point d’un prototype du dispositif (caméras et visiocasque de réalité virtuelle). Pour cela, nous avons dû choisir les équipements de capture et d’affichage d’images. Un travail de calibration colorimétrique sur ces équipements nous permet de relier grandeurs numériques (code RGB) et grandeurs physiques (luminance et chrominance). Cette étape est nécessaire pour réaliser les tests précités dans des conditions physiquement connues. Elle nous permet également de définir les caractéristiques physiques que devront posséder les équipements qui seront choisis pour réaliser le produit final, s’ils sont différents de ceux utilisés pendant nos travaux.Enfin, nous avons abordé la question des traitements à appliquer au signal capturé par la caméra. Nous avons proposé des traitements en temps réel sur la luminosité dans le but d’augmenter la luminosité dans les zones sombres de l’image et de baisser la luminosité dans les zones qui éblouissent le patient. Nous avons montré les limitations de l’imagerie classique et la nécessité de travailler sur des images HDR (high dynamic range) Nous avons comparé plusieurs méthodes pour permettre l’affichage de ces images HDR sur les écrans de plus faible dynamique, en recherchant les caractéristiques de l’image que ces méthodes doivent préserver au mieux, et en prenant en compte les performances visuelles des utilisateurs potentiels. Nous avons aussi proposé des traitements sur la couleur en augmentant le contraste et la saturation pour rendre les images mieux perceptibles par les patients qui souffrent de troubles de vision des couleurs
This thesis is part of a project conducted by the LGI2P research center (IMT Mines Ales). The project's final aim is to help people with vision disorders suffering from retinitis pigmentosa and glaucoma get back to work and improve their daily lives. The final device is designed to help people in their mobility activities: detecting obstacles, searching for visual signals, by addressing problems related to dazzling and haemeralopia affecting these potential users.The research of this thesis has several contributions to the project. First of all, parameters characterizing the residual vision of each user had to be defined. Indeed, each patient has his own light comfort conditions, which depend in particular on his pathology's progress: at each stage of the evolution of their disease, patients have specific minimum luminosity limits below which they no longer perceive the details in a scene, and also on the maximum luminosity above which they feel discomfort and pain. The definition of these limitations in luminosity will make it possible to parameterize the device and adapt it to each user. But there is no method to measure these limiting luminance levels. We have therefore participated in the design and development of specialized tests, and in the conduct of trials on visually impaired subjects, as part of a clinical trial led by the Nîmes University Hospital and the ARAMAV (institute specializing in low vision functional rehabilitation), for medical research. We have also proposed a new test to measure sensitivity to chromatic contrast, always with the aim of better adjusting the images displayed to users' vision.Then, we developed a prototype of the device (cameras and virtual reality video headset). In order to achieve these results, we had to choose the image capture and display equipment. A colorimetric calibration work on these equipments allowed us to link digital quantities (RGB code) and physical quantities (luminance and chrominance). This stage is required to perform the above tests under physically known conditions. It also allowed us to define the physical characteristics of the equipment that would be selected to produce the final product, whether they are different from those required during our work.Finally, we discussed the processing to be applied to the signal captured by the camera. We have proposed real-time brightness treatments to increase brightness in dark areas of the image and decrease brightness in areas that dazzle the patient. We have presented the limitations of conventional imaging and the necessity to work on HDR (high dynamic range) images. We have compared several methods to allow the display of these HDR images on screens with lower dynamic range, looking for the image characteristics that these methods should better preserve, and taking into consideration the visual performance of potential users. We have also suggested color treatments by increasing contrast and saturation to make images more perceptible to patients with color vision disorders

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Anani-Manyo, Nina K. "Computer Vision and Building Envelopes." Kent State University / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=kent1619539038754026.

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DeCock, Candace Eva. "Vision with Spectacles in Keratoconus." The Ohio State University, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=osu1245434360.

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Massing, Peter Allen. "The vision of my experience." The Ohio State University, 1989. http://rave.ohiolink.edu/etdc/view?acc_num=osu1303320851.

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Minichello, Michaela A. "Adult Strabismus and Vision Therapy." The Ohio State University, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=osu1429747867.

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Constantin, Fabien, and Pol Donnou. "Sport sponsorship from athletes' point of view." Thesis, Högskolan i Halmstad, Sektionen för ekonomi och teknik (SET), 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-19898.

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Powers, Gary Madison. "Impartiality and the personal point of view." Thesis, University of Oxford, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.302969.

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Cunningham, Terence Patrick. "Hypervalency : the spin-coupled point of view." Thesis, University of Liverpool, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.260400.

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Dissertations / Theses on the topic 'Vision; Point of view'

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