Дисертації з теми "Plant 3D reconstruction"
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Preuksakarn, Chakkrit. "Reconstructing plant architecture from 3D laser scanner data." Thesis, Montpellier 2, 2012. http://www.theses.fr/2012MON20116/document.
Повний текст джерелаIn the last decade, very realistic rendering of plant architectures have been produced in computer graphics applications. However, in the context of biology and agronomy, acquisition of accurate models of real plants is still a tedious task and a major bottleneck for the construction of quantitative models of plant development. Recently, 3D laser scanners made it possible to acquire 3D images on which each pixel has an associate depth corresponding to the distance between the scanner and the pinpointed surface of the object. Standard geometrical reconstructions fail on plants structures as they usually contain a complex set of discontinuous or branching surfaces distributed in space with varying orientations. In this thesis, we present a method for reconstructing virtual models of plants from laser scanning of real-world vegetation. Measuring plants with laser scanners produces data with different levels of precision. Points set are usually dense on the surface of the main branches, but only sparsely cover thin branches. The core of our method is to iteratively create the skeletal structure of the plant according to local density of point set. This is achieved thanks to a method that locally adapts to the levels of precision of the data by combining a contraction phase and a local point tracking algorithm. In addition, we present a quantitative evaluation procedure to compare our reconstructions against expertised structures of real plants. For this, we first explore the use of an edit distance between tree graphs. Alternatively, we formalize the comparison as an assignment problem to find the best matching between the two structures and quantify their differences
Schöler, Florian [Verfasser]. "3D Reconstruction of Plant Architecture by Grammar-based Modeling and Markov Chain Sampling / Florian Schöler." Bonn : Universitäts- und Landesbibliothek Bonn, 2014. http://d-nb.info/1060787245/34.
Повний текст джерелаBartoli, Adrien. "Reconstruction et alignement en vision 3D : points, droites, plans et caméras." Phd thesis, Grenoble INPG, 2003. http://tel.archives-ouvertes.fr/tel-00004360.
Повний текст джерелаKarlsson, Anette. "In-Plane Motion Correction in Reconstruction of non-Cartesian 3D-functional MRI." Thesis, Linköpings universitet, Datorseende, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-72056.
Повний текст джерелаNär patienter rör sig under en MRI-undersökning uppstår artefakter i den rekonstruerande bilden och därför är det önskvärt med rörelsekorrigering. En 2D- rörelsekorrigeringsalgoritm som är anpassad för PRESTO-CAN har tagits fram. PRESTO-CAN är en ny fMRI-metod för 3D där samplingen av k-rummet är radiell i (kx,kz)-planet och kartesisk i ky-riktningen. Rotations- och translationsrörelser kan estimeras separat då magnituden av signalen bara påverkas av rotationsrörelser. Eftersom data är samplat radiellt kan rotationen estimeras genom att hitta translationen i vinkelled med hjälp av cirkulär korrelation. Korrelation används även för att hitta translationen i i x- och z-riktningen. Test på simulerat data visar att rörelsekorrigeringsalgoritmen både detekterar och korrigerar för rörelser vilket leder till bilder med mycket mindre rörelseartefakter.
Dosch, Philippe. "Un environnement pour la reconstruction 3D d'édifices à partir de plans d'architecte." Nancy 1, 2000. http://docnum.univ-lorraine.fr/public/SCD_T_2000_0066_DOSCH.pdf.
Повний текст джерелаThis thesis is in line with the field of document analysis, and more precisely deals with graphics recognition. Our purpose is the construction of a 3D model of a building from the architectural drawings of its f1oors. For that, we have a set of analysis modules and a graphical user interface (GUI) allowing a human operator to control the processings to be pelformed in an optimal way. The major part of this thesis describes the various processings implemented, from the low-level (bitmap images processings) to the high-Ievel (vectorized data processings). We describe the choices which have led us to define a threelayered software architecture, hierarchally organized: A library of software components, an applicative layer grouping the various processings together and the GUI. The latter allows to directly interact on data to control the the analysis, and manages the man-machine cooperation. All the members of our research teams have been involved in this work, but our main contributions concem the design of the GUI, the spatial organization of processings (tiling), the extraction of middle-level features (dashed and dotted lines, symbols such as stairwell, etc. ) and matching algorithms to construct the 3D structure of a building, as weil as the software integration and the design of the GUI
Jonsson, Mikael. "Make it Flat : Detection and Correction of Planar Regions in Triangle Meshes." Thesis, Linköpings universitet, Datorseende, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-126589.
Повний текст джерелаKonsten att digitalt rekonstruera en verklig miljö har länge varit intressant för forskare. Nyligen har området även tilldragit sig mer och mer uppmärksamhet från företag som ser en möjlighet att föra den här typen av teknik till produkter på marknaden. I synnerhet är digital rekonstruktion av byggnader en nisch som har både stor potential och möjlighet till förbättring. Med denna bakgrund så presenterar detta examensarbete designen för och utvärderingen av en pipeline som skapats för att detektera och rätta till approximativt platta regioner i arkitektoniska miljöer. Miljöerna är 3D-rekonstruerade triangelmeshar skapade från RGB-bilder. Examensarbetet omfattar även utvärdering av olika komponenter för att uppnå detta, som avslutas med att de mest lämpliga komponenterna presenteras. Målet i korthet är att förbättra den visuella kvaliteten av en rekonstruerad modell. Den slutgiltiga pipelinen består av två övergripande block - ett för att detektera initiala plan och ett för att förbättra de funna planen. Det första blocket använder en multi-label energiformulering på grafen som beskriver den rekonstruerade ytan. Straffvärden tilldelas varje vertex och varje båge i grafen baserade på varje vertex label. På så sätt beskriver grafen ett Markov Random Field. Energin är sedan minimerad med alpha-expansion-algoritmen. Det andra blocket använder heuristiker för att låta planen växa, slå ihop närliggande plan och för att extrahera avvikande detaljer. Resultat på flera miljöer presenteras också för att påvisa att den visuella kvaliteten har förbättrats utan att rekonstruktionens noggrannhet har försämrats jämfört med ground truth-data.
Da, Costa Luis Eduardo. "Reconstruction de modèles 3D à partir d'information 2D partielle : application au cas d'une plante." Mémoire, École de technologie supérieure, 2007. http://espace.etsmtl.ca/573/1/DA_COSTA_Luis_Eduardo.pdf.
Повний текст джерелаHorna, Sébastien. "Reconstruction géométrique et topologique de complexes architecturaux 3D à partir de plans numériques 2D." Poitiers, 2008. http://theses.edel.univ-poitiers.fr/theses/2008/Horna-Sebastien/2008-Horna-Sebastien-These.pdf.
Повний текст джерелаVirtual architectural (indoor) scenes are often modelled in 3D for various types of simulation systems. For instance, some authors propose methods dedicated to lighting, heat transfer, acoustic or radio wave propagation simulations. These methods rely in most cases on a volumetric representation of the environment, with adjacency and incidence relationships. Unfortunately, many buildings data are only given by 2D plans and the 3D needs varies from one application to another. To solve these problems, we propose a formal representation of consistency constraints dedicated to building interiors and associated with a topological model. We show that such a representation can be used for : (i) reconstructing a 3D model from 2D architectural plans ; (ii) detecting automatically geometrical, topological and semantical inconsistencies ; (iii) designing automatic and semi-automatic operations to correct and enrich a 2D plan. All our constraints are homogeneously defined in 2D and 3D, implemented with generalized maps and used in modeling operations. We explain how this model can be successfully used with various ray-tracing methods
Da, Costa Luis Eduardo. "Reconstruction de modèles 3D à partir d'information 2D partielle : application au cas d'une plante /." Thèse, Montréal : École de technologie supérieure, 2007. http://proquest.umi.com/pqdweb?did=1397920901&sid=3&Fmt=2&clientId=46962&RQT=309&VName=PQD.
Повний текст джерела"Thèse présentée à l'École de technologie supérieure comme exigence partielle à l'obtention du doctorat en génie". CaQQUQ Bibliogr. : f. [173]-179. Également disponible en version électronique. CaQMUQET
Bui, Cao Vu. "Modélisation d'environnements intérieurs par reconstruction 3D en temps réel et extraction de plans architecturaux 2D." Thesis, Troyes, 2018. http://www.theses.fr/2018TROY0032.
Повний текст джерелаScene reconstruction is the process of building an accurate geometric model of one's environment from We explore the problem of complete scene reconstruction in indoor environments using mixed - data from the low-cost RGB-D camera and the inertial unit. The scanning process is realized in real-time, on the move with 6DoF of the numerizing system. We focus on computationally-constrained mobile systems, such as smartphone or tablet devices. Problematic issues present a set of fundamental challenges - estimating the state and trajectory of the device as it moves while scanning environment and utilizing lightweight data structures to hold the representation of the reconstructed scene. The system needs to be computationally and memory-efficient, so that it can run in real time, on-board the mobile device. The point-cloud resulted in the above module, which is non-structured and noisy cause of the quality of the low-cost sensor, needed a new method for the surface reconstruction. Our Dodecahedron Mapping is presented like a triangulation solution for the completed indoor environment scanning. After filtering and smoothing the point cloud, the algorithm tries to approximating the surface mesh by deforming and pasting the dodecahedron surface to the scanned point cloud. And the last stage of this research mission is to developing tools for the automatic extraction of 2D architectural plans from the 3D scanned building scene. This extracting process is also possible from the 3D point cloud or mesh by defining a section plane
Cura, Rémi. "Inverse procedural Street Modelling : from interactive to automatic reconstruction." Thesis, Paris Est, 2016. http://www.theses.fr/2016PESC1034/document.
Повний текст джерелаWorld urban population is growing fast, and so are cities, inducing an urgent need for city planning and management.Increasing amounts of data are required as cities are becoming larger, "Smarter", and as more related applications necessitate those data (planning, virtual tourism, traffic simulation, etc.).Data related to cities then become larger and are integrated into more complex city model.Roads and streets are an essential part of the city, being the interface between public and private space, and between urban usages.Modelling streets (or street reconstruction) is difficult because streets can be very different from each other (in layout, functions, morphology) and contain widely varying urban features (furniture, markings, traffic signs), at different scales.In this thesis, we propose an automatic and semi-automatic framework to model and reconstruct streets using the inverse procedural modelling paradigm.The main guiding principle is to generate a procedural generic model and then to adapt it to reality using observations.In our framework, a "best guess" road model is first generated from very little information (road axis network and associated attributes), that is available in most of national databases.This road model is then fitted to observations by combining in-base interactive user edition (using common GIS software as graphical interface) with semi-automated optimisation.The optimisation approach adapts the road model so it fits observations of urban features extracted from diverse sensing data.Both street generation (StreetGen) and interactions happen in a database server, as well as the management of large amount of street Lidar data (sensing data) as the observations using a Point Cloud Server.We test our methods on the entire Paris city, whose streets are generated in a few minutes, can be edited interactively (<0.3 s) by several concurrent users.Automatic fitting (few m) shows promising results (average distance to ground truth reduced from 2.0 m to 0.5m).In the future, this method could be mixed with others dedicated to reconstruction of buildings, vegetation, etc., so an affordable, precise, and up to date City model can be obtained quickly and semi-automatically.This will also allow to such models to be used in other application areas.Indeed, the possibility to have common, more generic, city models is an important challenge given the cost an complexity of their construction
Rother, Carsten. "Multi-View Reconstruction and Camera Recovery using a Real or Virtual Reference Plane." Doctoral thesis, KTH, Numerical Analysis and Computer Science, NADA, 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-3463.
Повний текст джерелаReconstructing a 3-dimensional scene from a set of2-dimensional images is a fundamental problem in computervision. A system capable of performing this task can be used inmany applications in robotics, architecture, archaeology,biometrics, human computer interaction and the movie andentertainment industry.
Most existing reconstruction approaches exploit one sourceof information to tackle the problem. This is the motion of thecamera, the 2D images are taken from different viewpoints. Weexploit an additional information source, the reference plane,which makes it possible to reconstruct difficult scenes whereother methods fail. A real scene plane may serve as thereference plane. Furthermore, there are many alternativetechniques to obtain virtual reference planes. For instance,orthogonal directions in the scene provide a virtual referenceplane, the plane at infinity, or images taken with a parallelprojection camera. A collection of known and novel referenceplane scenarios is presented in this thesis.
The main contribution of the thesis is a novel multi-viewreconstruction approach using a reference plane. The techniqueis applicable to three different feature types, points, linesand planes. The novelty of our approach is that all cameras andall features (off the reference plane) are reconstructedsimultaneously from a single linear system of imagemeasurements. It is based on the novel observation that camerasand features have a linear relationship if a reference plane isknown. In the absence of a reference plane, this relationshipis non-linear. Thus many previousmethods must reconstructfeatures and cameras sequentially. Another class of methods,popular in the literature, is factorization, but, in contrastto our approach, this has the serious practical drawback thatall features are required to be visible in all views. Extensiveexperiments show that our approach is superior to allpreviously suggested reference plane and non-reference planemethods for difficult reference plane scenarios.
Furthermore, the thesis studies scenes which do not have aunique reconstruction, so-called critical configurations. It isproven that in the presence of a reference plane the set ofcritical configurations is small.
Finally, the thesis introduces a complete, automaticmulti-view reconstruction system based on the reference planeapproach. The input data is a set of images and the output a 3Dpoint reconstruction together with the correspondingcameras.
Seck, Bassirou. "Display and Analysis of Tomographic Reconstructions of Multiple Synthetic Aperture LADAR (SAL) images." Wright State University / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=wright1547740781773769.
Повний текст джерелаSingels, Wynand. "An application of photogrammetry in the petrochemical industry." Thesis, Stellenbosch : Stellenbosch University, 2008. http://hdl.handle.net/10019.1/2296.
Повний текст джерелаWhen building or improving a petrochemical plant, drawings are used extensively in the design process. However, existing petrochemical plants seldom match their drawings, or the drawings are lost, forcing the need to generate a 3D model of the structure of the plant. In this thesis photogrammetry is investigated as a method of generating a digital 3D model of an existing plant. Camera modeling, target extraction and 3D reconstruction are discussed in detail, and a real-world system is investigated.
Lébraly, Pierre. "Etalonnage de caméras à champs disjoints et reconstruction 3D : Application à un robot mobile." Phd thesis, Université Blaise Pascal - Clermont-Ferrand II, 2012. http://tel.archives-ouvertes.fr/tel-00795259.
Повний текст джерелаBismack, Brian James. "Implementation of the Dosimetry Check Software Package in Computing 3D Patient Exit Dose Through Generation of a Deconvolution Kernel to be Used for Patients’ IMRT Treatment Plan QA." University of Toledo Health Science Campus / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=mco1290456365.
Повний текст джерелаGimenez, Lucile. "Outils numériques pour la reconstruction et l'analyse sémantique de représentations graphiques de bâtiments." Thesis, Paris 8, 2015. http://www.theses.fr/2015PA080047.
Повний текст джерелаMany buildings have to undergo major renovation to comply with regulations and environmental challenges. The BIM (Building Information Modeling) helps designers to make better-informed decisions, and results in more optimal energy-efficient designs. Such advanced design approaches require 3D digital models. However such models are not available for existing buildings. The aim of our work is to develop a method to generate 3D building models from existing buildings at low cost and in a reasonable time. We have chosen to work with 2D scanned plans. We assume that it is possible to find a paper plan for most buildings even if it is not always up-to-date and if the recognition quality is also dependent to the plan. The automatic reconstruction of a BIM from a paper plan is based on the extraction and identification of 3 main components: geometry (element shape), topology (links between elements) and semantics (object properties). During this process, some errors are generated which cannot be automatically corrected. This is why, we propose a novel approach based on punctual and guided human interventions to automatically identify and propose correction choices to the user to avoid error propagation.We describe the developed methodology to convert semi-automatically a 2D scanned plan into a BIM. A result analysis is done on 90 images. The following works is focused on the process genericity to test its robustness, the challenge of moving to scale and the multi-level management. The results highlight the pertinence of the error classification, identification and choices made to the user. The process is flexible in order to be completed by others data sources
Angladon, Vincent. "Room layout estimation on mobile devices." Phd thesis, Toulouse, INPT, 2018. http://oatao.univ-toulouse.fr/20745/1/ANGLADON_Vincent.pdf.
Повний текст джерелаDraréni, Jamil. "Exploitation de contraintes photométriques et géométriques en vision : application au suivi, au calibrage et à la reconstruction." Grenoble, 2010. http://www.theses.fr/2010GRENM061.
Повний текст джерелаThe topic of this thesis revolves around three fundamental problems in computer vision; namely, video tracking, camera calibration and shape recovery. The proposed methods are solely based on photometric and geometric constraints found in the images. Video tracking, usually performed on a video sequence, consists in tracking a region of interest, selected manually by an operator. We extend a successful tracking method by adding the ability to estimate the orientation of the tracked object. Furthermore, we consider another fundamental problem in computer vision: calibration. Here we tackle the problem of calibrating linear cameras (a. K. A: pushbroom)and video projectors. For the former one we propose a convenient plane-based calibration algorithm and for the latter, a calibration algorithm that does not require aphysical grid and a planar auto-calibration algorithm. Finally, we pointed our third research direction toward shape reconstruction using coplanar shadows. This technique is known to suffer from a bas-relief ambiguity if no extra information on the scene or light source is provided. We propose a simple method to reduce this ambiguity from four to a single parameter. We achieve this by taking into account the visibility of the light spots in the camera
Vala, Martin. "Analýza defektů na DPS za použití moderních optických metod." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2016. http://www.nusl.cz/ntk/nusl-254482.
Повний текст джерела張嘉峻. "Plane-Based Multi-View 3D Dense Reconstruction." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/70774976171125022226.
Повний текст джерела國立交通大學
多媒體工程研究所
99
This paper addresses 3D dense reconstruction of a scene/object from multiple photos taken by a calibrated camera. Unlike most of the existing methods which use a fixed-sized window to do two-view correlation matching for verifying the photo consistency across the multiple views, our method applies a multi-image matching without requiring a fixed-sized window. The reconstruction begins with extracting image features such as local min/max intensity or the like from the input images, and then applies the epipolar constraints to derive the matched feature pairs. The whole object surface is approximated by a set of planar surface patches in 3D space; that is, the object model consists of a set of oriented points or a point cloud in short. Each planar patch is initially represented by a plane equation derived from the associated line/point feature pairs. Next, an iterative optimization process is called for to refine the plane parameter to attain higher accuracy. Finally, a dense model for 3D model is accomplished. We apply our reconstruction method to synthetic images in order to check the geometry correctness and real images for robustness testing. The experimental results show that our reconstructed models generally look smoother and more accurate than the ones reconstructed by a top existing multi-view stereo method.
PENG, GUAN-YU, and 彭貫宇. "Floor plan-based 3D scene reconstruction and indoor positioning system." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/9kmz57.
Повний текст джерела國立臺北科技大學
資訊工程系
107
We have proposed a scene reconstruction technique to develop an indoor positioning system that incorporated augmented reality (AR). 3D scene reconstruction was achieved using floor plans, and low-power Bluetooth devices were used for indoor positioning. Suggestions on the deployment of Bluetooth devices were made using a placement algorithm so that administrator could easily set up a positioning environment with the smallest number of Bluetooth devices in optimal locations. Based on the positioning environment, this system provides AR functions including visualized navigation, messaging, and warnings for restricted areas.
Ralho, João Pedro Loureiro. "Learning Single-View Plane Prediction from autonomous driving datasets." Master's thesis, 2019. http://hdl.handle.net/10316/87852.
Повний текст джерелаA reconstrução 3D tradicional usando múltiplas imagens apresenta algumas dificuldades em cenas com pouca ou repetida textura, superfícies inclinadas, iluminação variada e especularidades. Este problema foi resolvido através de geometria planar (PPR), bastante frequente em estruturas construidas pelo ser humano. As primitivas planares são usadas para obter uma reconstrução mais precisa, geometricamente simples, e visualmente mais apelativa que uma núvem de pontos. Estimação de profundidade através de uma única imagem (SIDE) é uma ideia bastante apelativa que recentemente ganhou novo destaque devido à emergência de métodos de aprendizagem e de novas formas de gerar grandes conjuntos de dados RGB-D precisos. No fundo, esta dissertação pretende extender o trabalho desenvolvido em SIDE para reconstrução 3D usando primitivas planares através de uma única imagem (SI-PPR). Os métodos existentes apresentam alguma dificuldade em gerar bons resultados porque não existem grandes coleções de dados PPR precisos de cenas reais. Como tal, o objetivo desta dissertação é propor um pipeline para gerar de forma eficiente grandes coleções de dados PPR para retreinar métodos de estimação PPR. O pipeline é composto por três partes, uma responsável por gerar informação sobre a profundidade numa imagem através do colmap, segmentação manual dos planos verificados na imagem, e uma propagação automática da segmentação realizada e dos parâmetros dos planos para as imagens vizinhas usando uma nova estratégia com base em restrições geométricas e amostragem aleatória. O pipeline criado é capaz de gerar dados PPR com eficiência e precisão a partir de imagens reais.
Traditional 3D reconstruction using multiple images have some difficulties in dealing with scenes with little or repeated texture, slanted surfaces, variable illumination, and specularities. This problem was solved using planarity prior (PPR), which is quite common in man-made environments. Planar primitives are used for a more accurate, geometrically simple, and visually appealing reconstruction than a cloud of points. Single image depth estimation (SIDE) is a very appealing idea that has recently gained new prominence due to the emergence of learning methods and new ways to generate large accurate RGB-D datasets. This dissertation intends to extend the work developed in SIDE and work on single image piece-wise planar reconstruction (SI-PPR). Existing methods struggle in outputting accurate planar information from images because there are no large collections of accurate PPR data from real imagery. Therefore, this dissertation aims to propose a pipeline to efficiently generate large PPR datasets to re-train PPR estimation approaches. The pipeline is composed by three main stages, depth data generation using colmap, manual labeling of a small percentage of the images of the dataset, and automatic label and plane propagation to neighbouring views using a new strategy based on geometric constraints and random sampling. The pipeline created is able to efficiently and accurately generate PPR data from real images. -------------------------------------------------------------------
Jourdain, Mélissa. "Reconstruction 3D des artères par imagerie intravasculaire ultrasonore (IVUS) et angiographie monoplan." Thèse, 2009. http://hdl.handle.net/1866/6434.
Повний текст джерелаWang, Chia-Jui, and 王嘉銳. "Application of Stereo Machine Vision and L-Systems to 3D Reconstruction of Virtual Plants." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/79908033926491864612.
Повний текст джерела國立臺灣大學
生物產業機電工程學研究所
91
The objective of this study was to develop a 3D reconstruction system of virtual plants by using L-systems and stereo machine vision. The vegetable seedling was placed on a platform rotated by the stepping motor. Two CCD cameras were utilized to automatically capture three orthogonal images of each seedling. Elliptical Hough transform based on the top-view image was used to search the leaves. Furthermore, the whole structure of the vegetable seedling could be reconstructed by supplementing information from the front-view and side-view images. An algorithm developed by comparing the distance of leaf center with the area ratio of each leave in many sets was to determine the number of leaves by voting scheme. Hence, the geometric information including positions of internodes and leaves, and areas of leaves could be acquired. The performance of the machine vision system was illustrated with the measurement of the characteristics of cabbage and edible amaranth seedlings. The characteristics of seedlings were measured and their 3D structures were also reconstructed. For the simulation of virtual plant, the parametric L-system was improved by establishing the one-layer interpreting rules of strings to make it easier in modification and better performance of the parametric L-system. Each leave or petal could be easily added to the string by choosing the corresponding texture file and the alphabet. A model of virtual flower was implemented by adding the corresponding strings into the initial strings and rule strings with the inputs of the number, angle and length of the petal, and of the length and number of the pistil. The 2D models of leaves or petals were constructed by using two cubic Bézier curves fitted to the leaf image captured from the scanner or the CCD camera. The control points of Bézier curves can be further converted into two 16-control-point 3D Bézier surface models. In this study, OpenGL libraries and computer graphics techniques constructed the realistic virtual flowers and plants. The 3D structures of cabbages, orchids, and other plants were manually measured and reconstructed by using the developed L-systems. In addition, the virtual plants were successfully simulated by the stochastic L-system.
Draréni, Jamil. "Exploitation de contraintes photométriques et géométriques en vision : application au suivi, au calibrage et à la reconstruction." Thèse, 2010. http://hdl.handle.net/1866/4868.
Повний текст джерелаThe topic of this thesis revolves around three fundamental problems in computer vision; namely, video tracking, camera calibration and shape recovery. The proposed methods are solely based on photometric and geometric constraints found in the images. Video tracking, usually performed on a video sequence, consists in tracking a region of interest, selected manually by an operator. We extend a successful tracking method by adding the ability to estimate the orientation of the tracked object. Furthermore, we consider another fundamental problem in computer vision: cali- bration. Here we tackle the problem of calibrating linear cameras (a.k.a: pushbroom) and video projectors. For the former one we propose a convenient plane-based cali- bration algorithm and for the latter, a calibration algorithm that does not require a physical grid and a planar auto-calibration algorithm. Finally, we pointed our third research direction toward shape reconstruction using coplanar shadows. This technique is known to suffer from a bas-relief ambiguity if no extra information on the scene or light source is provided. We propose a simple method to reduce this ambiguity from four to a single parameter. We achieve this by taking into account the visibility of the light spots in the camera.
Cette thése a été réalisée dans le cadre d'une cotutelle avec l'Institut National Polytechnique de Grenoble (France). La recherche a été effectuée au sein des laboratoires de vision 3D (DIRO, UdM) et PERCEPTION-INRIA (Grenoble).