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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Analysis and Design of a Digital Spatio-temporal Filter for Image Processing

Lee, Yu-Lun 25 July 2010 (has links)
Along with rapid development of information technology, all kinds of algorithms have been presented, to achieve significant progress in image tracking. Most methods tend to identify features of moving objects, and filter out background components which do not meet these features. This thesis uses a spatio-temporal planar-resonant filter to accomplish moving object tracking tasks. Under the condition without prior knowledge about features of moving objects, choosing appropriate filter¡¦s parameters is able to enhance the object with a certain moving speed and reduce intensity of objects with different velocities. Nevertheless, this filter cannot solve the problem background filtering. Therefore, a homomorphic filtering with fast optical flow estimation is implemented to identify and separate the background and moving components in dynamic images. This thesis also considers different 3-D bandwidth parameters. To develop a systematic approach to design filter¡¦s parameters for actual implementations.
2

A Prototype For An Interactive And Dynamic Image-Based Relief Rendering System / En prototyp för ett interaktivt och dynamisktbildbaserat relief renderingssystem

Bakos, Niklas January 2002 (has links)
<p>In the research of developing arbitrary and unique virtual views from a real- world scene, a prototype of an interactive relief texture mapping system capable of processing video using dynamic image-based rendering, is developed in this master thesis. The process of deriving depth from recorded video using binocular stereopsis is presented, together with how the depth information is adjusted to be able to manipulate the orientation of the original scene. When the scene depth is known, the recorded organic and dynamic objects can be seen from viewpoints not available in the original video.</p>
3

Moving Object Detction In 2d And 3d Scenes

Sirtkaya, Salim 01 September 2004 (has links) (PDF)
This thesis describes the theoretical bases, development and testing of an integrated moving object detection framework in 2D and 3D scenes. The detection problem is analyzed in stationary and non-stationary camera sequences and different algorithms are developed for each case. Two methods are proposed in stationary camera sequences: background extraction followed by differencing and thresholding, and motion detection using optical flow field calculated by &ldquo / Kanade-Lucas Feature Tracker&rdquo / . For non-stationary camera sequences, different algorithms are developed based on the scene structure and camera motion characteristics. In planar scenes where the scene is flat or distant from the camera and/or when camera makes rotations only, a method is proposed that uses 2D parametric registration based on affine parameters of the dominant plane for independently moving object detection. A modified version of the 2D parametric registration approach is used when the scene is not planar but consists of a few number of planes at different depths, and camera makes translational motion. Optical flow field segmentation and sequential registration are the key points for this case. For 3D scenes, where the depth variation within the scene is high, a parallax rigidity based approach is developed for moving object detection. All these algorithms are integrated to form a unified independently moving object detector that works in stationary and non-stationary camera sequences and with different scene and camera motion structures. Optical flow field estimation and segmentation is used for this purpose.
4

A Prototype For An Interactive And Dynamic Image-Based Relief Rendering System / En prototyp för ett interaktivt och dynamisktbildbaserat relief renderingssystem

Bakos, Niklas January 2002 (has links)
In the research of developing arbitrary and unique virtual views from a real- world scene, a prototype of an interactive relief texture mapping system capable of processing video using dynamic image-based rendering, is developed in this master thesis. The process of deriving depth from recorded video using binocular stereopsis is presented, together with how the depth information is adjusted to be able to manipulate the orientation of the original scene. When the scene depth is known, the recorded organic and dynamic objects can be seen from viewpoints not available in the original video.
5

Mapeamento 3-D para robôs / 3-D mapping for robots

Baptista Júnior, Antonio 14 November 2013 (has links)
Na robótica, mapear o ambiente é tarefa importante, porque ela oferece informação para o planejamento e execução de movimentos do robô. Por este motivo, aqui são apresentados estudos que visam a construção de mapas 3-D e técnicas que auxiliam na tarefa de mapeamento. Quando são construídos mapas 3-D, é habilitado para outros pesquisadores e empresas de robótica a desenvolverem trabalhos de análise e planejamento de trajetórias em todos os seis graus de liberdade do corpo rígido que serve para modelar um robô móvel, robô manipulador ou robô móvel manipulador. Com uma representação do ambiente em 3-D, é aumentada a precisão do posicionamento do robô em relação ao ambiente e também o posicionamento de objetos que estão inseridos no campo de atuação do robô. Para solucionar o problema de mapeamento são apresentadas técnicas teóricas e suas aplicações em cada caso estudado. Nos experimentos realizados neste trabalho foi adotada a criação de mapas com grids (malhas) de ocupação. Vale lembrar, no entanto, que a construção de mapas por malhas de ocupação pressupõe o conhecimento do posicionamento do robô no ambiente. Neste trabalho foram conduzidos três experimentos e seus objetivos são redução de dados provenientes de falhas e redundâncias de informação com utilização de técnicas probabilísticas, detecção de movimento através da técnica de extração de fundo e mapeamento 3-D utilizando a técnica de ponto mais próximo. No experimento cujo o objetivo é reduzir os dados, foi possível reduzir para 4,43% a quantidade de pontos necessários para gerar a representação do ambiente com a utilização do algoritmo deste trabalho. O algoritmo de mapeamento 3-D feito com uso de modelos probabilísticos bem estabelecidos e disponíveis na literatura tem como base a probabilidade de eventos independentes e a proposta do trabalho envolvendo probabilidade a posteriori. O experimento de detecção de movimento foi gerado com a utilização da openCV e a tecnologia CUDA e utilizam a técnica do modelo de mistura gaussiana (GMM), foi analisado o tempo de processamento desempenhado por cada implementação e a qualidade do resultado obtido. Para obter uma representação precisa do ambiente foi conduzido o experimento que utiliza técnica iterativa do ponto mais próximo (ICP), para realização foi utilizado o sensor de movimento Kinect e os resultados apresentados não foram satisfatórios devido ao volume de dados adquiridos e a ausência de um sistema de estimativa da localização. / In robotics, map the environment is an important task, because it provides information for planning and executing movements of the robot. For this reason, studies presented here are aimed to build 3-D maps and techniques that aid in the task of mapping. When we build 3-D maps, we enable other researchers and robotics companies to develop analyzes and path planning in all six degrees of freedom rigid body that serves to model a mobile robot, manipulator or mobile robot manipulator.With a representation of the environment in 3-D, we increase the accuracy of the robot positioning in relation to the environment and also the positioning of objects that are inserted into the field of action of the robot. To solve the problem of mapping we presented theoretical techniques and their applications in each case studied.In the experiments in this work we adopted the creation of maps with grids of occupation. However, building grids of occupation assumes knowledge of the position of the robot on the environment.In this work we conducted three experiments and their aims are the reduction of data from failures and redundant information using probabilistic techniques, motion detection by background extraction technique and 3-D mapping technique using the closest point. In the experiment whose goal is to reduce the data has been further reduced to 4.43% the number of points required to generate the representation of the environment with the use of our algorithm.The algorithm of 3-D mapping done with probabilistic models available and well established in the literature is based on the probability of independent events and the proposed work involving the posterior probability.The motion detection experiment was performed with the use of openCV and CUDA technique using the Gaussian mixture model (GMM),and we analyzed the processing time and the quality of each implementation result.For an accurate representation of the environment was conducted the experiment using the technique of iterative closest point (ICP) was used to perform the motion sensor Kinect and the results were not satisfactory due to the volume of data acquired and the absence of a system location estimate.
6

Mapeamento 3-D para robôs / 3-D mapping for robots

Antonio Baptista Júnior 14 November 2013 (has links)
Na robótica, mapear o ambiente é tarefa importante, porque ela oferece informação para o planejamento e execução de movimentos do robô. Por este motivo, aqui são apresentados estudos que visam a construção de mapas 3-D e técnicas que auxiliam na tarefa de mapeamento. Quando são construídos mapas 3-D, é habilitado para outros pesquisadores e empresas de robótica a desenvolverem trabalhos de análise e planejamento de trajetórias em todos os seis graus de liberdade do corpo rígido que serve para modelar um robô móvel, robô manipulador ou robô móvel manipulador. Com uma representação do ambiente em 3-D, é aumentada a precisão do posicionamento do robô em relação ao ambiente e também o posicionamento de objetos que estão inseridos no campo de atuação do robô. Para solucionar o problema de mapeamento são apresentadas técnicas teóricas e suas aplicações em cada caso estudado. Nos experimentos realizados neste trabalho foi adotada a criação de mapas com grids (malhas) de ocupação. Vale lembrar, no entanto, que a construção de mapas por malhas de ocupação pressupõe o conhecimento do posicionamento do robô no ambiente. Neste trabalho foram conduzidos três experimentos e seus objetivos são redução de dados provenientes de falhas e redundâncias de informação com utilização de técnicas probabilísticas, detecção de movimento através da técnica de extração de fundo e mapeamento 3-D utilizando a técnica de ponto mais próximo. No experimento cujo o objetivo é reduzir os dados, foi possível reduzir para 4,43% a quantidade de pontos necessários para gerar a representação do ambiente com a utilização do algoritmo deste trabalho. O algoritmo de mapeamento 3-D feito com uso de modelos probabilísticos bem estabelecidos e disponíveis na literatura tem como base a probabilidade de eventos independentes e a proposta do trabalho envolvendo probabilidade a posteriori. O experimento de detecção de movimento foi gerado com a utilização da openCV e a tecnologia CUDA e utilizam a técnica do modelo de mistura gaussiana (GMM), foi analisado o tempo de processamento desempenhado por cada implementação e a qualidade do resultado obtido. Para obter uma representação precisa do ambiente foi conduzido o experimento que utiliza técnica iterativa do ponto mais próximo (ICP), para realização foi utilizado o sensor de movimento Kinect e os resultados apresentados não foram satisfatórios devido ao volume de dados adquiridos e a ausência de um sistema de estimativa da localização. / In robotics, map the environment is an important task, because it provides information for planning and executing movements of the robot. For this reason, studies presented here are aimed to build 3-D maps and techniques that aid in the task of mapping. When we build 3-D maps, we enable other researchers and robotics companies to develop analyzes and path planning in all six degrees of freedom rigid body that serves to model a mobile robot, manipulator or mobile robot manipulator.With a representation of the environment in 3-D, we increase the accuracy of the robot positioning in relation to the environment and also the positioning of objects that are inserted into the field of action of the robot. To solve the problem of mapping we presented theoretical techniques and their applications in each case studied.In the experiments in this work we adopted the creation of maps with grids of occupation. However, building grids of occupation assumes knowledge of the position of the robot on the environment.In this work we conducted three experiments and their aims are the reduction of data from failures and redundant information using probabilistic techniques, motion detection by background extraction technique and 3-D mapping technique using the closest point. In the experiment whose goal is to reduce the data has been further reduced to 4.43% the number of points required to generate the representation of the environment with the use of our algorithm.The algorithm of 3-D mapping done with probabilistic models available and well established in the literature is based on the probability of independent events and the proposed work involving the posterior probability.The motion detection experiment was performed with the use of openCV and CUDA technique using the Gaussian mixture model (GMM),and we analyzed the processing time and the quality of each implementation result.For an accurate representation of the environment was conducted the experiment using the technique of iterative closest point (ICP) was used to perform the motion sensor Kinect and the results were not satisfactory due to the volume of data acquired and the absence of a system location estimate.
7

Prototypování fotografické kompozice pomocí rozšířené reality / Prototyping of Photographic Composition Using Augmented Reality

Salát, Marek January 2016 (has links)
The thesis deals with an image processing problem called image matting. The problem involves detection of a foreground and background in an image with minimal user interaction using trimaps. Foreground detection is used in image composition. The goal of the thesis is to apply already known algorithms, in this case A Global sampling matting, in an Android application. The most important result is an intuitive application that can be used for making creative viral photos. Agile methodology is applied throughout the whole application development cycle. From the very beginning, the application is publicly available as a minimum viable product on Google play. The work&#8217;s contribution is in optimization of the mentioned algorithm for use in mobile devices and parallelization on a GPU, together with a publicly available application.

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