The purpose of this project is to implement, analyze and compare visual odometry approaches to help the localization task in autonomous vehicles. The stereo visual odometry algorithm Libviso2 is compared with a proposed omnidirectional multi-camera approach. The proposed method consists of performing monocular visual odometry on all cameras individually and selecting the best estimate through a voting scheme involving all cameras. The omnidirectionality of the vision system allows the part of the surroundings richest in features to be used in the relative pose estimation. Experiments are carried out using cameras Bumblebee XB3 and Ladybug 2, fixed on the roof of a vehicle. The voting process of the proposed omnidirectional multi-camera method leads to some improvements relatively to the individual monocular estimates. However, stereo visual odometry provides considerably more accurate results. / O objetivo deste mestrado é implementar, analisar e comparar abordagens de odometria visual, de forma a contribuir para a localização de um veículo autônomo. O algoritmo de odometria visual estéreo Libviso2 é comparado com um método proposto, que usa um sistema multi-câmera omnidirecional. De acordo com este método, odometria visual monocular é calculada para cada câmera individualmente e, seguidamente, a melhor estimativa é selecionada através de um processo de votação que involve todas as câmeras. O fato de o sistema de visão ser omnidirecional faz com que a parte dos arredores mais rica em características possa sempre ser usada para estimar a pose relativa do veículo. Nas experiências são utilizadas as câmeras Bumblebee XB3 e Ladybug 2, fixadas no teto de um veículo. O processo de votação do método multi-câmera omnidirecional proposto apresenta melhorias relativamente às estimativas monoculares individuais. No entanto, a odometria visual estéreo fornece resultados mais precisos.

Submitted by EVERTON SIMÕES DA MOTTA (evmotta08@gmail.com) on 2017-01-05T13:08:55Z No. of bitstreams: 1 DissertacaoFinalCorrigida-v5.pdf: 7335404 bytes, checksum: fa4ba2ff69cd4d2dd72b1b5cb475111b (MD5) / Approved for entry into archive by Juliano Benedito Ferreira (julianoferreira@reitoria.unesp.br) on 2017-01-09T17:01:51Z (GMT) No. of bitstreams: 1 motta_es_me_rcla.pdf: 7335404 bytes, checksum: fa4ba2ff69cd4d2dd72b1b5cb475111b (MD5) / Made available in DSpace on 2017-01-09T17:01:51Z (GMT). No. of bitstreams: 1 motta_es_me_rcla.pdf: 7335404 bytes, checksum: fa4ba2ff69cd4d2dd72b1b5cb475111b (MD5) Previous issue date: 2016-12-22 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Sistemas de captura de movimentos humanos vêm sendo cada dia mais estudados, tanto pela área de Visão Computacional, quanto por grandes empresas do setor de entretenimento. São sistemas capazes de rastrear a posição e orientação das articulações do corpo e sua trajetória no espaço durante um intervalo de tempo. São utilizados em diversas aplicações, tais como em jogos digitais, animação de personagens virtuais para cinema e televisão, reconhecimento gestual, medicina de reabilitação, e outras. O surgimento de novos dispositivos de baixo custo e boa resolução que fornecem informações de profundidade, tem motivado novas pesquisas para a utilização dos mesmos. No entanto, sistemas que se baseiam somente em informações de profundidade (geralmente sistemas em tempo real) não apresentam uma alta acurácia no rastreamento do movimento. Considerando este contexto, o presente trabalho teve como objetivo principal, o desenvolvimento de um método de captura de movimentos humanos utilizando único sensor RGB-D, combinando informações de textura da imagem e de profundidade, que são associados a um esqueleto virtual, conseguindo-se uma maior acurácia em comparação com os métodos baseados apenas em profundidade. Tal método não visa aplicações de tempo real, mas sim, uma maior acurácia em comparação com os métodos baseados apenas em profundidade. / Human motion capture systems are being increasingly studied, in the area of computer vision and also by major entertainment industries. These systems are able to track the position and orientation of joints of the body and its trajectory in space over a period of time. They are used in various applications such as digital games, animation of virtual characters for film and television, gesture recognition, medical rehabilitation, etc. The emergence of new low-cost and good resolution devices that provide depth information has prompted new research. However, systems that are based only on depth information (usually real-time systems) do not present a high accuracy in movement tracking. Considering this context, this thesis project presents the development of a method for capturing human movements using only one RGB-D sensor, combining captured texture from the image and depth information in order to obtain a higher accuracy, which are associated with a virtual skeleton. This method is not intended for real-time applications, but those that require greater accuracy, such as the animation of virtual characters in video and medical rehabilitation.

Sistemas de Interação Humano-Computador baseados em toque são uma tecnologia disseminada em tablets, smartphones e notebooks. Trata-se de um grande avanço que aumenta a facilidade de comunicação e, ao mesmo tempo, diminui a necessidade de interfaces como mouse e teclado. Entretanto, a superfície de interação utilizada por esses sistemas normalmente é equipada com sensores para a captação dos movimentos realizados pelo usuário, o que impossibilita transformar uma superfície planar qualquer (uma mesa, por exemplo) em uma superfície de interação. Por outro lado, a popularização de sensores de profundidade a partir do lançamento do Microsoft Kinect propiciou o desenvolvimento de sistemas que adotam objetos do dia a dia como superfícies de interação. Nesta dissertação é proposta uma interface natural para interação com superfícies planares utilizando uma câmera RGB-D em posição descendente. Inicialmente, o plano de interação é localizado na nuvem de pontos 3D através de uma variação do algoritmo RANSAC com coerência temporal. Objetos acima do plano são segmentados a partir da transformada watershed baseada em uma função de energia que combina cor, profundidade e informação de confiança. A cor de pele é utilizada para isolar as mãos, e os dedos que interagem com o plano são identificados por um novo processo de esqueletonização 2D. Finalmente, as pontas dos dedos são rastreadas com o uso do algoritmo Húngaro, e o filtro de Kalman é usado para produzir trajetórias mais suaves. Para demonstrar a utilidade da técnica, foi desenvolvido um protótipo que permite ao usuário desenhar em uma superfície de forma natural e intuitiva. / Touch-based Human-Computer Interfaces (HCIs) are a widespread technology present in tablets, smartphones, and notebooks. This is a breakthrough which increases the ease of communication and at the same time reduces the need for interfaces such as mouse and keyboard. However, the interaction surface used by these systems is usually equipped with sensors to capture the movements made by the user, making it impossible to substitute this surface by any other such as a table, for example. On the other hand, the progress of commercial 3D depth sensing technologies in the past five years, having as a keystone Microsoft’s Kinect sensor, has increased the interest in 3D hand gesture recognition using depth data. In this dissertation, we present a natural Human-Computer Interface (HCI) for interaction with planar surfaces using a topdown RGB-D camera. Initially, the interaction plane is located in the 3D point cloud by using a variation of RANSAC with temporal coherence. Off-plane objects are segmented using the watershed transform based on an energy function that combines color, depth and confidence information. Skin color information is used to isolate the hand(s), and a novel 2D skeletonization process identifies the interaction fingers. Finally, the fingertips are tracked using the Hungarian algorithm, and a Kalman filter is applied to produce smoother trajectories. To demonstrate the usefulness of the technique, we also developed a prototype in which the user can draw on the surface using lines and sprays in a natural way.

O principal intento deste trabalho é demonstrar como a combinação de resultados de modelos radiométricos e de análises do limite de resolução de imagens produzem impactos positivos não apenas no projeto óptico de retinógrafos de alta resolução, mas que também geram ferramentas que auxiliam na definição da arquitetura de todo o equipamento, considerando, inclusive, os limites impostos por normas internacionais para a segurança do paciente em relação a radiação emitida na realização dos exames. Particularmente ao projeto óptico, foram desenvolvidos os sistemas de iluminação e imageamento da retina, onde se destacam duas propostas de metodologias: a primeira para a implementação da técnica de eliminação das bem conhecidas retro-reflexões geradas no conjunto óptico que é comum à iluminação e ao imageamento da retina, e a segunda para a obtenção de soluções efetivas em sistemas imageadores, que prima pela diminuição da sensibilidade dos componentes aos erros que são introduzidos pelos processos de fabricação e montagem. Analisando os resultados obtidos com o protótipo, foram validados os sistemas e modelos propostos, que se tornaram parte integrante de um produto oftalmológico aprovado para a comercialização, o retinógrafo Kiron. / The fundamental objective of this work is to demonstrate how radiometric models and analysis of the limit of resolution can provide not only positive impacts to the optical project of high resolution fundus cameras, but also creates tools to perform an optimization of all the equipment, considering the limits imposed by international standards to ensure security to the patient regarding the equipment radiation emission. In the optical project in particular, the imaging and illuminating systems of the retina were developed, in which stands out two proposed methodologies: first, to eliminate the well known retro-reflections in the common optical assembly of the imaging and illuminating systems, and a second one that helps the optical designer to find effective solutions in imaging systems, focused in the reduction of the component sensitivity to the fabrication and assembly processes errors. Analyzing the results from the prototypes the systems and the models proposed were validated, becoming integrant part of an ophthalmic product approved for commercialization, the Kiron fundus camera.

This thesis presents a secure digital camera (SDC) that inserts biometric data into images found in forms of identification such as the newly proposed electronic passport. However, putting biometric data in passports makes the data vulnerable for theft, causing privacy related issues. An effective solution to combating unauthorized access such as skimming (obtaining data from the passport's owner who did not willingly submit the data) or eavesdropping (intercepting information as it moves from the chip to the reader) could be judicious use of watermarking and encryption at the source end of the biometric process in hardware like digital camera or scanners etc. To address such issues, a novel approach and its architecture in the framework of a digital camera, conceptualized as an SDC is presented. The SDC inserts biometric data into passport image with the aid of watermarking and encryption processes. The VLSI (very large scale integration) architecture of the functional units of the SDC such as watermarking and encryption unit is presented. The result of the hardware implementation of Rijndael advanced encryption standard (AES) and a discrete cosine transform (DCT) based visible and invisible watermarking algorithm is presented. The prototype chip can carry out simultaneous encryption and watermarking, which to our knowledge is the first of its kind. The encryption unit has a throughput of 500 Mbit/s and the visible and invisible watermarking unit has a max frequency of 96.31 MHz and 256 MHz respectively.

El texto completo de este trabajo no está disponible en el Repositorio Académico UPC por restricciones de la casa editorial donde ha sido publicado. / This article is about the problem and development of a fashion virtual assistant proposed by using a Kinect v2 camera and image processing, for fashion retail stores. It comes up mainly as a response to the inability of providing unique experiences during the shopping process through the use of diverse devices. Because of this, similar virtual assistant solutions, oriented to provide clothing recommendations, were analyzed to be able to provide software that could give a more personalized suggestion for the users based on their physical characteristics. / Revisión por pares

Smart cities utilize IoT cameras in a rushing pace. However, these high technological connected devices are back doors to safe systems. Implementation of high technological solutions without concerning other important aspects as information security and the factor of trust violates not only the quality aspect of the solutions, but also breaches the privacy of individuals. Secure solutions that reserve the trust of individuals with the help of high technological solutions is therefore significant. This study is aimed to investigate and find answer to how IoT camera solutions for smart cities can include all three of the important factors, which contributes for a deeper understanding of the whole product development process` possible improvements. Through a qualitative approach the research questions are investigated which resulted in a contribution that support the academic world of information security in presenting the importance of correct communication, collaboration and the including of the three factors during the development process of IoT camera solutions for smart cities. The results are open for further investigation as observed during research, but also key findings and recommendations are offered to the stakeholders of the IoT camera solution development industry.

This thesis is done by two students from Blekinge Institute of Technology as an end of the master of engineering program with emphasis on applied mechanics. The thesis is done in cooperation with Axis Communications AB in Lund which develop surveillance cameras. The task was to design and implement an Angular Vibration Testing Equipment. Axis needs this to test their surveillance cameras for angular vibrations. These vibrations occur usually on cameras located on poles placed at roads and at train stations. The thesis has been carried out in three different phases where the first phase handled a deeper understanding of the problem, planning and investigating of related works. Axis has a solution for smaller cameras called Shakespeare MK I and this was used as an inspiration for us. The second phase included concept generation and concept evaluation. This has been done with brainstorming, workshop and concept scoring. At the last phase a prototype was built and tested and a detailed design was made. Two versions of the prototype were made and they showed that the concept works well. The project resulted in a working prototype that can transform linear motion to rotation around two axes. A drawing and a cost calculation were made for the final concept. The final construction is still not completely optimized and has improvement and adjustment possibilities that might be needed.

Thesis: M.S., Massachusetts Institute of Technology, Department of Mechanical Engineering, 1979 / Bibliography: leaves 38-39. / by Michio Takahashi. / M.S. / M.S. Massachusetts Institute of Technology, Department of Mechanical Engineering

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