Résumé : Thèse de DoctoratL’importance de l’imagerie médicale comme élément principal dans plusieurs application médicales et diagnostiques de soin de santé est indispensable. L’intégration des données utiles obtenues des diverses images est vitale pour une analyse appropriée de l’information contenues dans ces images sous observation. Pour que ce processus d’intégration réussisse, une procédure appelée recalage d’image est nécessaire.Le but du recalage d’image consiste à aligner deux images afin de trouver une transformation géométrique qui place une des deux images dans la meilleure correspondance spatiale possible avec l’autre image en optimisant un critère de recalage. Les deux images sont dites image cible et image source. Les méthodes de recalage d’image consistent à avoir référencées par des points de contrôle. Ceci est suivi d’une transformation de recalage qui associe les deux images et d’une fonction définie sur base de la mesure de similarité qui a pour but de mesurer la valeur qualitative de proximité ou encore de degré de concordance entre l’image cible et l’image source. Enfin, un optimisateur qui cherche à trouver la transformation optimale au sein du champ de solution de la recherche, est appliqué.Cette recherche présente un algorithme automatique de recalage d’image dont le but est de résoudre le problème du recalage d’image à multiple modes sur une paire des clichés de tomographie par ordinateur (CT) faite sur les poumons. Dans cette méthode, une étude comparative entre la méthode classique d’optimisation par algorithme du gradient à pas fixe et celle de l’algorithme évolutionniste est menée. L’objectif de cette recherche est d’effectuer l’optimisation par des techniques de recalage d’image ainsi qu’évaluer la performance de ces mêmes techniques afin de doter les spécialistes du domaine médical d’une estimation de combien précis et robuste le processus de recalage serait. Les paires des clichés obtenues de la tomographie par ordinateur faite sur les poumons sont recalées en utilisant l’information mutuelle comme mesure de similarité, la transformation affine ainsi que l’interpolation linéaire. Un optimisateur qui recherche la transformation optimale au sein de l’espace de recherche est appliqué afin de minimiser la fonction économique (fonction objectif).Les études de détermination d’un modèle de transformation qui dépend des paramètres de transformation et de l’identification des mesures de similarité basée sur l’intensité du voxel ont été menées. En alignant la transformation avec les points de control, trois modèles de transformation sont comparés. La transformation affine produit la meilleure reconstitution d’image en comparaison aux transformations non réfléchissantes et projectives. Les résultats de cette recherche sont assez comparables à celles rapportées dans le challenge de recherche EMPIRE 10 et sont conformes à la fois aux principes théoriques aussi bien qu’aux applications pratiques.La contribution de cette recherche réside dans son potentiel à améliorer la compréhension scientifique du recalage d’image des organes anatomiques du corps humain. Cette recherche établie ainsi une base pour une recherche avancée sur l’évaluation de la performance des techniques de recalage et la validation des procédures sur d’autres types d’algorithmes et domaines d’application du recalage d’images comme la détection, la communication par satellite, l’ingénierie biomédicale, la robotique, les systèmes d'information géographique (SIG) et de localisation parmi tant d’autres / D’Tech Thesis SummaryThe importance of medical imaging as a core component of several medical application and healthcare diagnosis cannot be over emphasised. Integration of useful data acquired from different images is vital for proper analysis of information contained in the images under observation. For the integration process to be successful, a procedure referred to as image registration is necessary.The purpose of image registration is to align two images in order to find a geometric transformation that brings one image into the best possible spatial correspondence with another image by optimising a registration criterion. The two images are known as the target image and the source image. Image registration methods consist of having the two images referenced with control points. This is followed by a registration transformation that relates the two images and a similarity metric function that aims to measure the qualitative value of closeness or degree of fitness between the target image and the source image. Finally, an optimiser which seeks an optimal transformation inside the defined solution search space is performed.This research presents an automated image registration algorithm for solving multimodal image registration on lung Computer Tomography (CT) scan pairs, where a comparison between regular step gradient descent optimisation technique and evolutionary optimisation was investigated. The aim of this research is to carry out optimisation and performance evaluation of image registration techniques in order to provide medical specialists with estimation on how accurate and robust the registration process is. Lung CT scan pairs are registered using mutual information as a similarity measure, affine transformation and linear interpolation. In order to minimise the cost function, an optimiser, which seeks the optimal transformation inside the defined search space is applied.Determination of a transformation model that depends on transformation parameters and identification of similarity metric based on voxel intensity were carried out. By fitting transformation to control points, three transformation models were compared. Affine transformation produced the best recovered image when compared to non-reflective similarity and projective transformations. The results of this research compares well with documented results from EMPIRE 10 Challenge research and conforms to both theoretical principles as well as practical applications.The contribution of this research is its potential to increase the scientific understanding of image registration of anatomical body organs. It lays a basis for further research in performance evaluation of registration techniques and validation of procedures to other types of algorithms and image registration application areas, such as remote sensing, satellite communication, biomedical engineering, robotics, geographical information systems and mapping, among others

Orientador: João Antonio Pereira / Resumo: O objetivo específico deste trabalho é estender as capacidades da técnica de rastreamento de pontos em 3 dimensões (three-dimensional point tracking – 3DPT) para identificar as características dinâmicas de estruturas grandes e complexas, tais como pás de turbina eólica. Um sistema multi-camera (composto de múltiplos sistemas de estéreo visão calibrados independentemente) é desenvolvido para obter alta resolução espacial de pontos discretos a partir de medidas de deslocamento sobre grandes áreas. Uma proposta de técnica de costura é apresentada e empregada para executar o alinhamento de duas nuvens de pontos, obtidas com a técnica 3DPT, de uma estrutura sob excitação dinâmica. Três diferentes algoritmos de registro de nuvens de pontos são propostos para executar a junção das nuvens de pontos de cada sistema estéreo, análise de componentes principais (Principal Component Analysis - PCA), decomposição de valores singulares (Singular value Decomposition - SVD) e ponto mais próximo iterativo (Iterative Closest Point - ICP). Além disso, análise modal operacional em conjunto com o sistema de medição multi-camera e as técnicas de registro de nuvens de pontos são usadas para determinar a viabilidade de usar medidas ópticas (e.g. three-dimensional point tracking – 3DPT) para estimar os parâmetros modais de uma pá de gerador eólico comparando seus resultados com técnicas de medição mais convencionais. / Abstract: The specific objective of this research is to extend the capabilities of three-dimensional (3D) Point Tracking (PT) to identify the dynamic characteristics of large and complex structures, such as utility-scale wind turbine blades. A multi-camera system (composed of multiple independently calibrated stereovision systems) is developed to obtain high spatial resolution of discrete points from displacement measurement over very large areas. A proposal of stitching techniques is presented and employed to perform the alignment of two point clouds, obtained with 3DPT measurement, of a structure under dynamic excitation. The point cloud registration techniques are exploited as a technique for dynamic measuring (displacement) of large structures with high spatial resolution of the model. Three different image registration algorithms are proposed to perform the junction of the points clouds of each stereo system, Principal Component Analysis (PCA), Singular value Decomposition (SVD) and Iterative Closest Point (ICP). Furthermore, operational modal analysis in conjunction with the multi-camera measurement system and registration techniques are used to determine the feasibility of using optical measurements (e.g. three-dimensional point tracking (3DPT)) to estimate the modal parameters of a utility-scale wind turbine blade by comparing with traditional techniques. / Doutor

Submitted by DANILO DAMASCENO SABINO (engdanilosabino@gmail.com) on 2018-07-03T16:00:40Z No. of bitstreams: 1 DaniloSabino_TeseVersaoFinal.pdf: 4134991 bytes, checksum: 888a0a610949d5417be468fa2b94c7c8 (MD5) / Rejected by Cristina Alexandra de Godoy null (cristina@adm.feis.unesp.br), reason: Danilo, seu trabalho foi redigido em língua inglesa, mas é preciso inserir o título em português no campo "título em outro idioma". Tentamos contato por e-mail mas sem resposta. Assim, solicitamos que refaça a submissão do seu trabalho com essa informação. on 2018-07-06T14:47:31Z (GMT) / Submitted by DANILO DAMASCENO SABINO (engdanilosabino@gmail.com) on 2018-09-24T22:07:38Z No. of bitstreams: 1 DaniloSabino_TeseVersaoFinal.pdf: 4134991 bytes, checksum: 888a0a610949d5417be468fa2b94c7c8 (MD5) / Approved for entry into archive by Cristina Alexandra de Godoy null (cristina@adm.feis.unesp.br) on 2018-09-25T11:47:26Z (GMT) No. of bitstreams: 1 sabino_dd_dr_ilha.pdf: 4134991 bytes, checksum: 888a0a610949d5417be468fa2b94c7c8 (MD5) / Made available in DSpace on 2018-09-25T11:47:26Z (GMT). No. of bitstreams: 1 sabino_dd_dr_ilha.pdf: 4134991 bytes, checksum: 888a0a610949d5417be468fa2b94c7c8 (MD5) Previous issue date: 2018-02-01 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O objetivo específico deste trabalho é estender as capacidades da técnica de rastreamento de pontos em 3 dimensões (three-dimensional point tracking – 3DPT) para identificar as características dinâmicas de estruturas grandes e complexas, tais como pás de turbina eólica. Um sistema multi-camera (composto de múltiplos sistemas de estéreo visão calibrados independentemente) é desenvolvido para obter alta resolução espacial de pontos discretos a partir de medidas de deslocamento sobre grandes áreas. Uma proposta de técnica de costura é apresentada e empregada para executar o alinhamento de duas nuvens de pontos, obtidas com a técnica 3DPT, de uma estrutura sob excitação dinâmica. Três diferentes algoritmos de registro de nuvens de pontos são propostos para executar a junção das nuvens de pontos de cada sistema estéreo, análise de componentes principais (Principal Component Analysis - PCA), decomposição de valores singulares (Singular value Decomposition - SVD) e ponto mais próximo iterativo (Iterative Closest Point - ICP). Além disso, análise modal operacional em conjunto com o sistema de medição multi-camera e as técnicas de registro de nuvens de pontos são usadas para determinar a viabilidade de usar medidas ópticas (e.g. three-dimensional point tracking – 3DPT) para estimar os parâmetros modais de uma pá de gerador eólico comparando seus resultados com técnicas de medição mais convencionais. / The specific objective of this research is to extend the capabilities of three-dimensional (3D) Point Tracking (PT) to identify the dynamic characteristics of large and complex structures, such as utility-scale wind turbine blades. A multi-camera system (composed of multiple independently calibrated stereovision systems) is developed to obtain high spatial resolution of discrete points from displacement measurement over very large areas. A proposal of stitching techniques is presented and employed to perform the alignment of two point clouds, obtained with 3DPT measurement, of a structure under dynamic excitation. The point cloud registration techniques are exploited as a technique for dynamic measuring (displacement) of large structures with high spatial resolution of the model. Three different image registration algorithms are proposed to perform the junction of the points clouds of each stereo system, Principal Component Analysis (PCA), Singular value Decomposition (SVD) and Iterative Closest Point (ICP). Furthermore, operational modal analysis in conjunction with the multi-camera measurement system and registration techniques are used to determine the feasibility of using optical measurements (e.g. three-dimensional point tracking (3DPT)) to estimate the modal parameters of a utility-scale wind turbine blade by comparing with traditional techniques.