Download or read book 3D Metric Reconstruction from Uncalibrated Circular Motion Image Sequences written by Huang Zhong and published by Open Dissertation Press. This book was released on 2017-01-27 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This dissertation, "3D Metric Reconstruction From Uncalibrated Circular Motion Image Sequences" by Huang, Zhong, 鐘煌, was obtained from The University of Hong Kong (Pokfulam, Hong Kong) and is being sold pursuant to Creative Commons: Attribution 3.0 Hong Kong License. The content of this dissertation has not been altered in any way. We have altered the formatting in order to facilitate the ease of printing and reading of the dissertation. All rights not granted by the above license are retained by the author. Abstract: Abstract of thesis entitled 3D Metric Reconstruction from Uncalibrated Circular Motion Image Sequences submitted by Zhong Huang for the degree of Doctor of Philosophy at The University of Hong Kong May 2006 Circular motion is a practical motion for model acquisition. This thesis addresses the problem of metric reconstruction from uncalibrated circular motion image sequences from both the theoretical and practical viewpoints. The cameras are assumed to have constant intrinsic parameters, but the actual camera motion need not be known. A stratified geometric approach is taken to devise solutions. Algorithms for motion estimation, metric reconstruction and surface extraction are developed, by which an object model can be reconstructed systematically. First, a reconstruction method for circular motion is developed with the aim of estimating the unknown rotation angles of the camera robustly. This is achieved by enforcing the knowledge of the type of motion (i.e. the rotational motion constraint) in a factorization-based projective reconstruction, yielding what is called a circular projective reconstruction. Furthermore, a three-stage reconstruction approach with image points incrementally added in different stages of reconstructions is presented for computing a circular projective reconstruction from a long circular motion image sequence. This approach can cope with the missing data problem which inherently exists in a long image sequence. Second, the problem of computing a metric reconstruction from a circular projective reconstruction is considered. Two camera calibration methods are II proposed for resolving the metric reconstruction ambiguity in a circular projective reconstruction by exploring available calibration constraints. The methods are based on a new decomposition of a rectifying homography and developed for the cases involving one circular motion image sequence or one circular motion image sequence with one additional image. Finally, a fast model reconstruction method is proposed to extract the surface of an object from a calibrated circular motion image sequence. It is shown that 3D rim curves with known order enclosing the object can be reconstructed by means of the object silhouettes and feature points. These ordered rim curves allow a triangulated surface mesh of the object model to be constructed efficiently. Throughout the thesis, experimental results are given to demonstrate the performance of the proposed algorithms, and these results are shown to be both accurate and stable. III DOI: 10.5353/th_b3704379 Subjects: Three-dimensional imaging Image reconstruction Cameras - Calibration Algorithms

Download or read book Three Dimensional Metric Reconstruction from Uncalibrated Circular Motion Image Sequences written by Huang Zhong and published by . This book was released on 2006 with total page 336 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book 3D Reconstruction and Camera Calibration from Circular Motion Image Sequences written by Yan Li and published by Open Dissertation Press. This book was released on 2017-01-27 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This dissertation, "3D Reconstruction and Camera Calibration From Circular-motion Image Sequences" by Yan, Li, 李燕, was obtained from The University of Hong Kong (Pokfulam, Hong Kong) and is being sold pursuant to Creative Commons: Attribution 3.0 Hong Kong License. The content of this dissertation has not been altered in any way. We have altered the formatting in order to facilitate the ease of printing and reading of the dissertation. All rights not granted by the above license are retained by the author. Abstract: Abstract of thesis entitled "3D Reconstruction and Camera Calibration from Circular-Motion Image Sequences" Submitted by Li Yan for the degree of Doctor of Philosophy at The University of Hong Kong in December 2005 This thesis investigates the problem of 3D reconstruction from circular motion image sequences. The problem is normally resolved in two steps: projective reconstruction and then metric reconstruction by self-calibration. A key question considered in this thesis is how to make use of the circular motion information to improve the reconstruction accuracy and reduce the reconstruction ambiguity. The information is previously utilized by identifying the fixed image entities (e.g. the image of the rotation axis, vanishing line of the motion plane, etc). These fixed entities, however, only exist in constant intrinsic parameter sequences. In this thesis, circular motion constraints, which are valid for varying intrinsic parameter (e.g. zooming/refocusing) cameras, are formulated from the movement of camera center and principal plane. Based on the constraints, several novel algorithms are developed for each step of the whole 3D reconstruction procedure. For image sequences with known rotation angles, a circular projective reconstruction algorithm is proposed. We first formulate the circular motion constraints in the Euclidean frame, and then deduce the most general form of reconstruction in a projective frame that satisfies the circular motion constraints. The constraints are gradually enforced during an iterative process, resulting in a circular projective reconstruction. This approach can be used to deal with both cases of constant and varying intrinsic parameters. It is proved that the circular projective reconstruction retrieves metric reconstruction up to a two-parameter ambiguity representing a projective distortion along the rotation axis of the circular motion. Based on the circular projective reconstruction, a hierarchical self-calibration algorithm is proposed to estimate the remaining two parameters. Closed-form expressions of the absolute conic and its image are deduced in terms of the two parameters, which are then determined with zero-skew and unit aspect ratio assumptions. Alternatively, starting from a general (rather than circular) projective reconstruction, a stratified self-calibration algorithm is proposed to upgrade the projective reconstruction directly to a metric one. In this case, the plane at infinity is first identified with (i) the circular motion constraint on camera center and (ii) zero-skew and unit aspect ratio assumptions. With the knowledge of the plane at infinity, the camera calibration matrices can be readily obtained. All the above algorithms assume that the rotation angles are known. In the case if the angles are unknown, we provide two novel rotation angle recovery methods. For constant intrinsic parameter sequences, rotation angles can be recovered by using the fixed image entities. For varying intrinsic parameter sequences, it is shown that the movements of the camera center and principal plane form two concentric circles on the motion plane. By identifying the corresponding conic loci in 3D projective frame, the geometry of circular motion on the motion plane can be recovered. Compared with existing methods, the new method is more flexible in that it allows the intrinsic parameters to vary, and is simpler by avoi

Download or read book Three Dimensional Reconstruction and Camera Calibration from Circular motion Image Sequences written by Yan Li (Ph.D.) and published by . This book was released on 2005 with total page 344 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book 3D Reconstruction from Multiple Images written by Theo Moons and published by Now Publishers Inc. This book was released on 2009-10-23 with total page 128 pages. Available in PDF, EPUB and Kindle. Book excerpt: The issue discusses methods to extract 3-dimensional (3D) models from plain images. In particular, the 3D information is obtained from images for which the camera parameters are unknown. The principles underlying such uncalibrated structure-from-motion methods are outlined. First, a short review of 3D acquisition technologies puts such methods in a wider context, and highlights their important advantages. Then, the actual theory behind this line of research is given. The authors have tried to keep the text maximally self-contained, therefore also avoiding to rely on an extensive knowledge of the projective concepts that usually appear in texts about self-calibration 3D methods. Rather, mathematical explanations that are more amenable to intuition are given. The explanation of the theory includes the stratification of reconstructions obtained from image pairs as well as metric reconstruction on the basis of more than 2 images combined with some additional knowledge about the cameras used. Readers who want to obtain more practical information about how to implement such uncalibrated structure-from-motion pipelines may be interested in two more Foundations and Trends issues written by the same authors. Together with this issue they can be read as a single tutorial on the subject.

Download or read book Advances in Computational Vision and Medical Image Processing written by Joao Tavares and published by Springer Science & Business Media. This book was released on 2008-12-21 with total page 296 pages. Available in PDF, EPUB and Kindle. Book excerpt: Computational methodologies of signal processing and imaging analysis, namely considering 2D and 3D images, are commonly used in different applications of the human society. For example, Computational Vision systems are progressively used for surveillance tasks, traf?c analysis, recognition process, inspection p- poses, human-machine interfaces, 3D vision and deformation analysis. One of the main characteristics of the Computational Vision domain is its int- multidisciplinary. In fact, in this domain, methodologies of several more fundam- tal sciences, such as Informatics, Mathematics, Statistics, Psychology, Mechanics and Physics are usually used. Besides this inter-multidisciplinary characteristic, one of the main reasons that contributes for the continually effort done in this domain of the human knowledge is the number of applications in the medical area. For instance, it is possible to consider the use of statistical or physical procedures on medical images in order to model the represented structures. This modeling can have different goals, for example: shape reconstruction, segmentation, registration, behavior interpretation and simulation, motion and deformation analysis, virtual reality, computer-assisted therapy or tissue characterization. The main objective of the ECCOMAS Thematic Conferences on Computational Vision and Medical Image Processing (VIPimage) is to promote a comprehensive forum for discussion on the recent advances in the related ?elds trying to id- tify widespread areas of potential collaboration between researchers of different sciences.

Download or read book Dissertation Abstracts International written by and published by . This book was released on 2008 with total page 980 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Variation Based Dense 3D Reconstruction written by Sven Painer and published by Springer. This book was released on 2016-03-08 with total page 87 pages. Available in PDF, EPUB and Kindle. Book excerpt: In his master thesis, Sven Painer develops, implements, and evaluates a method to reconstruct the liver surface from monocular mini-laparoscopic sequences. The principal focus of his research is to create a basis for helping clinicians to write reports with quantitative descriptions of the liver surface. A Structure from Motion approach is performed to do a sparse reconstruction of the liver surface and subsequently this information is used in a variation based dense 3D reconstruction. The algorithms are formulated in a causal way, enabling the implementation to be run in real-time on an adequate hardware platform. The results show a significant performance increase and pave the way to give clinicians a feedback during video capturing to improve the quality of the reconstruction in the near future.

Download or read book Metric 3D reconstruction from Unordered and Uncalibrated Image Collections written by and published by . This book was released on 2013 with total page 68 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Image Analysis written by Josef Bigün and published by Springer Science & Business Media. This book was released on 2003-06-25 with total page 1196 pages. Available in PDF, EPUB and Kindle. Book excerpt: The excellently received call for papers of the 13th Scandinavian Conference on Image Analysis, June 29-July 2 (SCIA 2003) resulted in the selected articles of this proceedings. Additionally the volume also contains invited contributions from - Ivar Austvoll, Stavanger University College (NO), - Lars B? a? ath, Halmstad University (SE), - Ewert Bengtsson, Uppsala University (SE), - Rasmus Larsen, Technical University of Denmark (DK), - Jussi Parkkinen, University of Joensuu (FI), - Pietro Perona, California Institute of Technology (US) which brings the total number of articles to 152. The theme of the papers are dominated by the categories - Feature extraction - Depth and surface - Medical image processing - Shape analysis - Segmentation and spatial grouping - Coding and representation - Motion analysis - Texture analysis - Color analysis - Indexing and categorization which also represent the topical groupings of this book. The particularly strong response to the feature extraction, depth and surface, and medical image processing themes makes us believe that these areas are c- rently expansive, partly because of the rich set of problems which remain to be addressed.

Download or read book Computer Vision ECCV 2022 Workshops written by Leonid Karlinsky and published by Springer Nature. This book was released on 2023-02-17 with total page 797 pages. Available in PDF, EPUB and Kindle. Book excerpt: The 8-volume set, comprising the LNCS books 13801 until 13809, constitutes the refereed proceedings of 38 out of the 60 workshops held at the 17th European Conference on Computer Vision, ECCV 2022. The conference took place in Tel Aviv, Israel, during October 23-27, 2022; the workshops were held hybrid or online. The 367 full papers included in this volume set were carefully reviewed and selected for inclusion in the ECCV 2022 workshop proceedings. They were organized in individual parts as follows: Part I: W01 - AI for Space; W02 - Vision for Art; W03 - Adversarial Robustness in the Real World; W04 - Autonomous Vehicle Vision Part II: W05 - Learning With Limited and Imperfect Data; W06 - Advances in Image Manipulation; Part III: W07 - Medical Computer Vision; W08 - Computer Vision for Metaverse; W09 - Self-Supervised Learning: What Is Next?; Part IV: W10 - Self-Supervised Learning for Next-Generation Industry-Level Autonomous Driving; W11 - ISIC Skin Image Analysis; W12 - Cross-Modal Human-Robot Interaction; W13 - Text in Everything; W14 - BioImage Computing; W15 - Visual Object-Oriented Learning Meets Interaction: Discovery, Representations, and Applications; W16 - AI for Creative Video Editing and Understanding; W17 - Visual Inductive Priors for Data-Efficient Deep Learning; W18 - Mobile Intelligent Photography and Imaging; Part V: W19 - People Analysis: From Face, Body and Fashion to 3D Virtual Avatars; W20 - Safe Artificial Intelligence for Automated Driving; W21 - Real-World Surveillance: Applications and Challenges; W22 - Affective Behavior Analysis In-the-Wild; Part VI: W23 - Visual Perception for Navigation in Human Environments: The JackRabbot Human Body Pose Dataset and Benchmark; W24 - Distributed Smart Cameras; W25 - Causality in Vision; W26 - In-Vehicle Sensing and Monitorization; W27 - Assistive Computer Vision and Robotics; W28 - Computational Aspects of Deep Learning; Part VII: W29 - Computer Vision for Civil and Infrastructure Engineering; W30 - AI-Enabled Medical Image Analysis: Digital Pathology and Radiology/COVID19; W31 - Compositional and Multimodal Perception; Part VIII: W32 - Uncertainty Quantification for Computer Vision; W33 - Recovering 6D Object Pose; W34 - Drawings and Abstract Imagery: Representation and Analysis; W35 - Sign Language Understanding; W36 - A Challenge for Out-of-Distribution Generalization in Computer Vision; W37 - Vision With Biased or Scarce Data; W38 - Visual Object Tracking Challenge.

Download or read book Automatic Calibration and Reconstruction for Active Vision Systems written by Beiwei Zhang and published by Springer Science & Business Media. This book was released on 2012-01-02 with total page 169 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this book, the design of two new planar patterns for camera calibration of intrinsic parameters is addressed and a line-based method for distortion correction is suggested. The dynamic calibration of structured light systems, which consist of a camera and a projector is also treated. Also, the 3D Euclidean reconstruction by using the image-to-world transformation is investigated. Lastly, linear calibration algorithms for the catadioptric camera are considered, and the homographic matrix and fundamental matrix are extensively studied. In these methods, analytic solutions are provided for the computational efficiency and redundancy in the data can be easily incorporated to improve reliability of the estimations. This volume will therefore prove valuable and practical tool for researchers and practioners working in image processing and computer vision and related subjects.

Download or read book Projective Reconstruction and Metric Models from Uncalibrated Video Sequences written by Daniel Thomas Oram and published by . This book was released on 2001 with total page 274 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book 3D Reconstruction from Uncalibrated Images written by and published by . This book was released on 2000 with total page 101 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Structure from Motion from Uncalibrated Digital Image Sequences written by David N. R. McKinnon and published by . This book was released on 2002 with total page 133 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Feature Based 3D Reconstruction of Man Made Scenes from Image Sequences written by Xiaofeng Zhang and published by . This book was released on 2002 with total page 161 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Computer Vision ECCV 2002 written by Anders Heyden and published by Springer. This book was released on 2003-08-01 with total page 837 pages. Available in PDF, EPUB and Kindle. Book excerpt: Premiering in 1990 in Antibes, France, the European Conference on Computer Vision, ECCV, has been held biennially at venues all around Europe. These conferences have been very successful, making ECCV a major event to the computer vision community. ECCV 2002 was the seventh in the series. The privilege of organizing it was shared by three universities: The IT University of Copenhagen, the University of Copenhagen, and Lund University, with the conference venue in Copenhagen. These universities lie ̈ geographically close in the vivid Oresund region, which lies partly in Denmark and partly in Sweden, with the newly built bridge (opened summer 2000) crossing the sound that formerly divided the countries. We are very happy to report that this year’s conference attracted more papers than ever before, with around 600 submissions. Still, together with the conference board, we decided to keep the tradition of holding ECCV as a single track conference. Each paper was anonymously refereed by three different reviewers. For the ?nal selection, for the ?rst time for ECCV, a system with area chairs was used. These met with the program chairsinLundfortwodaysinFebruary2002toselectwhatbecame45oralpresentations and 181 posters.Also at this meeting the selection was made without knowledge of the authors’identity.