Download or read book 3D Reconstruction of Deformable Surfaces Using Isometry written by Ajad Chhatkuli and published by . This book was released on 2017 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Local Analytic and Global Convex Methods for the 3D Reconstruction of Isometric Deformable Surfaces written by Ajad Chhatkuli and published by . This book was released on 2016 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis contributes to the problem of 3D reconstruction for deformable surfaces using a single camera. In order to model surface deformation, we use the isometric prior because many real object deformations are near-isometric. Isometry implies that the surface cannot stretch or compress. We tackle two different problems. The first is called Shape-from-Template where the object's deformed shape is computed from a single image and a texture-mapped 3D template of the object surface. Previous methods propose a differential model of the problem and compute the local analytic solutions. In the methods the solution related to the depth-gradient is discarded and only the depth solution is used. We demonstrate that the depth solution lacks stability as the projection geometry tends to affine. We provide alternative methods based on the local analytic solutions of first-order quantities, such as the depth-gradient or surface normals. Our methods are stable in all projection geometries. The second type of problem, called Non-Rigid Shape-from-Motion is the more general templatefree reconstruction scenario. In this case one obtains the object's shapes from a set of images where it appears deformed. We contribute to this problem for both local and global solutions using the perspective camera. In the local or point-wise method, we solve for the surface normal at each point assuming infinitesimal planarity of the surface. We then compute the surface by integration. In the global method we find a convex relaxation of the problem. This is based on relaxing isometry to inextensibility and maximizing the surface's average depth. This solution combines all constraints into a single convex optimization program to compute depth and works for a sparse point representation of the surface. We detail the extensive experiments that were used to demonstrate the effectiveness of each of the proposed methods. The experiments show that our local template-free solution performs better than most of the previous methods. Our local template-based method and our global template-free method performs better than the state-of-the-art methods with robustness to correspondence noise. In particular, we are able to reconstruct difficult, non-smooth and articulating deformations with the latter; while with the former we can accurately reconstruct large deformations with images taken at very long focal lengths.
Download or read book Image based Deformable 3D Reconstruction Using Differential Geometry and Cartan s Connections written by Shaifali Parashar and published by . This book was released on 2017 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Reconstructing the 3D shape of objects from multiple images is an important goal in computer vision and has been extensively studied for both rigid and non-rigid (or deformable) objects. Structure-from-Motion (SfM) is an algorithm that performs the 3D reconstruction of rigid objects using the inter-image visual motion from multiple images obtained from a moving camera. SfM is a very accurate and stable solution. Deformable 3D reconstruction, however, has been widely studied for monocular images (obtained from a single camera) and still remains an open research problem. The current methods exploit visual cues such as the inter-image visual motion and shading in order to formalise a reconstruction algorithm. This thesis focuses on the use of the inter-image visual motion for solving this problem. Two types of scenarios exist in the literature: 1) Non-Rigid Structure-from-Motion (NRSfM) and 2) Shape-from-Template (SfT). The goal of NRSfM is to reconstruct multiple shapes of a deformable object as viewed in multiple images while SfT (also referred to as template-based reconstruction) uses a single image of a deformed object and its 3D template (a textured 3D shape of the object in one configuration) to recover the deformed shape of the object. We propose an NRSfM method to reconstruct the deformable surfaces undergoing isometric deformations (the objects do not stretch or shrink under an isometric deformation) using Riemannian geometry. This allows NRSfM to be expressed in terms of Partial Differential Equations (PDE) and to be solved algebraically. We show that the problem has linear complexity and the reconstruction algorithm has a very low computational cost compared to existing NRSfM methods. This work motivated us to use differential geometry and Cartan's theory of connections to model NRSfM, which led to the possibility of extending the solution to deformations other than isometry. In fact, this led to a unified theoretical framework for modelling and solving both NRSfM and SfT for various types of deformations. In addition, it also makes it possible to have a solution to SfT which does not require an explicit modelling of deformation. An important point is that most of the NRSfM and SfT methods reconstruct the thin-shell surface of the object. The reconstruction of the entire volume (the thin-shell surface and the interior) has not been explored yet. We propose the first SfT method that reconstructs the entire volume of a deformable object.
Download or read book Deformable Surface 3D Reconstruction from Monocular Images written by Mathieu Salzmann and published by Morgan & Claypool Publishers. This book was released on 2011 with total page 114 pages. Available in PDF, EPUB and Kindle. Book excerpt: 7. Future directions -- Bibliography -- Authors' biographies.
Download or read book Deformable Surface 3D Reconstruction from Monocular Images written by Amit Roy-Chowdhury and published by Springer Nature. This book was released on 2022-05-31 with total page 99 pages. Available in PDF, EPUB and Kindle. Book excerpt: Being able to recover the shape of 3D deformable surfaces from a single video stream would make it possible to field reconstruction systems that run on widely available hardware without requiring specialized devices. However, because many different 3D shapes can have virtually the same projection, such monocular shape recovery is inherently ambiguous. In this survey, we will review the two main classes of techniques that have proved most effective so far: The template-based methods that rely on establishing correspondences with a reference image in which the shape is already known, and non-rigid structure-from-motion techniques that exploit points tracked across the sequences to reconstruct a completely unknown shape. In both cases, we will formalize the approach, discuss its inherent ambiguities, and present the practical solutions that have been proposed to resolve them. To conclude, we will suggest directions for future research. Table of Contents: Introduction / Early Approaches to Non-Rigid Reconstruction / Formalizing Template-Based Reconstruction / Performing Template-Based Reconstruction / Formalizing Non-Rigid Structure from Motion / Performing Non-Rigid Structure from Motion / Future Directions
Download or read book Mathematical Methods for Objects Reconstruction written by Emiliano Cristiani and published by Springer Nature. This book was released on 2023-07-31 with total page 185 pages. Available in PDF, EPUB and Kindle. Book excerpt: The volume collects several contributions to the INDAM workshop Mathematical Methods for Objects Reconstruction: from 3D Vision to 3D Printing held in Rome, February, 2021. The goal of the workshop was to discuss new methods and conceptual structures for managing these challenging problems. The chapters reflect this goal and the authors are academic researchers and some experts from industry working in the areas of 3D modeling, computer vision, 3D printing and/or developing new mathematical methods for these problems. The contributions present methodologies and challenges raised by the emergence of large-scale 3D reconstruction applications and low-cost 3D printers. The volume collects complementary knowledges from different areas of mathematics, computer science and engineering on research topics related to 3D printing, which are, so far, widely unexplored. Young researchers and future scientific leaders in the field of 3D data acquisition, 3D scene reconstruction, and 3D printing software development will find an excellent introduction to these problems and to the mathematical techniques necessary to solve them.
Download or read book Computer Vision ECCV 2016 written by Bastian Leibe and published by Springer. This book was released on 2016-09-15 with total page 893 pages. Available in PDF, EPUB and Kindle. Book excerpt: The eight-volume set comprising LNCS volumes 9905-9912 constitutes the refereed proceedings of the 14th European Conference on Computer Vision, ECCV 2016, held in Amsterdam, The Netherlands, in October 2016. The 415 revised papers presented were carefully reviewed and selected from 1480 submissions. The papers cover all aspects of computer vision and pattern recognition such as 3D computer vision; computational photography, sensing and display; face and gesture; low-level vision and image processing; motion and tracking; optimization methods; physics-based vision, photometry and shape-from-X; recognition: detection, categorization, indexing, matching; segmentation, grouping and shape representation; statistical methods and learning; video: events, activities and surveillance; applications. They are organized in topical sections on detection, recognition and retrieval; scene understanding; optimization; image and video processing; learning; action, activity and tracking; 3D; and 9 poster sessions.
Download or read book Computer Vision ECCV 2014 written by David Fleet and published by Springer. This book was released on 2014-08-14 with total page 871 pages. Available in PDF, EPUB and Kindle. Book excerpt: The seven-volume set comprising LNCS volumes 8689-8695 constitutes the refereed proceedings of the 13th European Conference on Computer Vision, ECCV 2014, held in Zurich, Switzerland, in September 2014. The 363 revised papers presented were carefully reviewed and selected from 1444 submissions. The papers are organized in topical sections on tracking and activity recognition; recognition; learning and inference; structure from motion and feature matching; computational photography and low-level vision; vision; segmentation and saliency; context and 3D scenes; motion and 3D scene analysis; and poster sessions.
Download or read book Advances in Visual Computing written by George Bebis and published by Springer. This book was released on 2014-12-02 with total page 989 pages. Available in PDF, EPUB and Kindle. Book excerpt: The two volume set LNCS 8887 and 8888 constitutes the refereed proceedings of the 10th International Symposium on Visual Computing, ISVC 2014, held in Las Vegas, NV, USA. The 74 revised full papers and 55 poster papers presented together with 39 special track papers were carefully reviewed and selected from more than 280 submissions. The papers are organized in topical sections: Part I (LNCS 8887) comprises computational bioimaging, computer graphics; motion, tracking, feature extraction and matching, segmentation, visualization, mapping, modeling and surface reconstruction, unmanned autonomous systems, medical imaging, tracking for human activity monitoring, intelligent transportation systems, visual perception and robotic systems. Part II (LNCS 8888) comprises topics such as computational bioimaging , recognition, computer vision, applications, face processing and recognition, virtual reality, and the poster sessions.
Download or read book Advances in Photometric 3D Reconstruction written by Jean-Denis Durou and published by Springer Nature. This book was released on 2020-09-16 with total page 239 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents the latest advances in photometric 3D reconstruction. It provides the reader with an overview of the state of the art in the field, and of the latest research into both the theoretical foundations of photometric 3D reconstruction and its practical application in several fields (including security, medicine, cultural heritage and archiving, and engineering). These techniques play a crucial role within such emerging technologies as 3D printing, since they permit the direct conversion of an image into a solid object. The book covers both theoretical analysis and real-world applications, highlighting the importance of deepening interdisciplinary skills, and as such will be of interest to both academic researchers and practitioners from the computer vision and mathematical 3D modeling communities, as well as engineers involved in 3D printing. No prior background is required beyond a general knowledge of classical computer vision models, numerical methods for optimization, and partial differential equations.
Download or read book Computer Vision ECCV 2018 written by Vittorio Ferrari and published by Springer. This book was released on 2018-10-08 with total page 851 pages. Available in PDF, EPUB and Kindle. Book excerpt: The sixteen-volume set comprising the LNCS volumes 11205-11220 constitutes the refereed proceedings of the 15th European Conference on Computer Vision, ECCV 2018, held in Munich, Germany, in September 2018.The 776 revised papers presented were carefully reviewed and selected from 2439 submissions. The papers are organized in topical sections on learning for vision; computational photography; human analysis; human sensing; stereo and reconstruction; optimization; matching and recognition; video attention; and poster sessions.
Download or read book Computer Vision ECCV 2004 written by Tomas Pajdla and published by Springer Science & Business Media. This book was released on 2004-04-28 with total page 648 pages. Available in PDF, EPUB and Kindle. Book excerpt: The four-volume set comprising LNCS volumes 3021/3022/3023/3024 constitutes the refereed proceedings of the 8th European Conference on Computer Vision, ECCV 2004, held in Prague, Czech Republic, in May 2004. The 190 revised papers presented were carefully reviewed and selected from a total of 555 papers submitted. The four books span the entire range of current issues in computer vision. The papers are organized in topical sections on tracking; feature-based object detection and recognition; geometry; texture; learning and recognition; information-based image processing; scale space, flow, and restoration; 2D shape detection and recognition; and 3D shape representation and reconstruction.
Download or read book Resolving Ambiguities in Monocular 3D Reconstruction of Deformable Surfaces written by Aydin Varol and published by . This book was released on 2012 with total page 115 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book State of the Art Sensors Technology in Spain 2017 Volume 1 written by Gonzalo Pajares Martinsanz and published by MDPI. This book was released on 2018-05-22 with total page 403 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is a printed edition of the Special Issue "State-of-the-Art Sensors Technology in Spain 2017" that was published in Sensors
Download or read book Stereo Based Three Dimensional Model Acquisition and Motion Detection written by Ting Yu and published by . This book was released on 2010 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Deformable models have a long tradition in computer graphics and computer vision. This thesis looks at the capture of surface deformation based on stereo vision. In recent years, 3D reconstruction and motion detection has attracted great attention. In this thesis a framework for 3D reconstruction from mutli-view images followed by isometry-based motion detection is proposed. For 3D reconstruction, the thesis proposes a multi-view stereo algorithm based on well-known window-based matching combined with fusion of multiple matching results. To improve the matching result, some low-level image processing algorithms, camera calibration and background detection are utilized. For window-based matching, a new hybrid matching method is introduced by combining both, a measure of intensity difference and intensity distribution difference. Multiple MVS pointclouds from different reference views are fused with two new fusion strategies to generate a better final reconstruction. To characterize the performance of our matching method and fusion strategies, an evaluation based on the quality of reconstruction is given in the thesis. Based on 3D pointclouds of object surface obtained with stereo, the deformation of the surface is captured. To generate dense motion vectors over a deformed surface, a simple window-based 3D flow method is applied by using isometry of the observed surface as its primary matching constraint. The method uses feature points as anchoring references of the surface deformation. Given a set of matched features no other intensity information is used and hence the method can tolerate intensity changes over time. The approach is shown to work well on two example scenes which capture non-rigid isometric and general deformations. The thesis also presents experiments demonstrating the stability of the geodesic approximation employed in the isometry-based matching when the 3D pointclouds are sparse.
Download or read book Contributions to Monocular Deformable 3D Reconstruction written by Mathias Gallardo and published by . This book was released on 2018 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Monocular deformable 3D reconstruction is the general problem of recovering the 3D shape of a deformable object from monocular 2D images. Several scenarios have emerged: the Shape-from-Template (SfT) and the Non-Rigid Structure-from-Motion (NRSfM) are two approaches intensively studied for their practicability. The former uses a single image depicting the deforming object and a template (a textured 3D shape of this object in a reference pose). The latter does not use a template, but uses several images and recovers the 3D shape in each image. Both approaches rely on the motion of correspondences between the images and deformation priors, which restrict their use to well-textured surfaces which deform smoothly. This thesis advances the state-of-the-art in SfT and NRSfM in two main directions. The first direction is to study SfT for the case of 1D templates (i.e. curved, thin structures such as ropes and cables). The second direction is to develop algorithms in SfT and NRSfM that exploit multiple visual cues and can solve complex, real-world cases which were previously unsolved. We focus on isometric deformations and reconstruct the outer part of the object. The technical and scientific contributions of this thesis are divided into four parts. The first part of this thesis studies the case of a curvilinear template embedded in 2D or 3D space, referred to Curve SfT. We propose a thorough theoretical analysis and practical solutions for Curve SfT. Despite its apparent simplicity, Curve SfT appears to be a complex problem: it cannot be solved locally using exact non-holonomic partial differential equation and is only solvable up to a finite number of ambiguous solutions. A major technical contribution is a computational solution based on our theory, which generates all the ambiguous solutions.The second part of this thesis deals with a limitation of SfT methods: reconstructing creases. This is due to the sparsity of the motion constraint and regularization. We propose two contributions which rely on a non-convex energy minimization framework. First, we complement the motion constraint with a robust boundary contour constraint. Second, we implicitly model creases with a dense mesh-based surface representation and an associated robust smoothing constraint, which deactivates curvature smoothing automatically where needed, without knowing a priori the crease location. The third part of this thesis is dedicated to another limitation of SfT: reconstructing poorly-textured surfaces. This is due to correspondences which cannot be obtained so easily on poorly-textured surfaces (either sparse or dense). As shading reveals details on poorly-textured surfaces, we propose to combine shading and SfT. We have two contributions. The first is a cascaded initialization which estimates sequentially the surface's deformation, the scene illumination, the camera response and then the surface albedos from deformed monocular images. The second is to integrate shading to our previous energy minimization framework for simultaneously refining deformation and photometric parameters.The last part of this thesis relaxes the knowledge of the template and addresses two limitations of NRSfM: reconstructing poorly-textured surfaces with creases. Our major contribution is an extension of the second framework to recover jointly the 3D shapes of all input images and the surface albedos without any template.
Download or read book 3D Reconstruction of Deformable Surface Based on Binocular Vision written by Bo Yang and published by . This book was released on 2020-11-30 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The 3D reconstruction of deformable surfaces is a classical problem in the field of computer vision, which has many important applications in virtual reality, surgical navigation, and training. For example, accurate 3D reconstruction for intracavitary soft-tissue scenes based on a stereo-endoscope can effectively promote surgeons and surgical robots' perception in a Minimally Invasive Surgery (MIS), and thus improve the precision and safety of surgical operations. However, the dynamic deformable soft-tissues bring great challenges for accurate reconstruction. This book provides an in-depth discussion about the binocular reconstruction techniques for dynamic deformable surfaces such as beating heart surfaces. The camera models and calibration methods used for stereo vision are introduced first. The classical stereo matching methods are then presented. The deformable-model-based reconstruction methods are discussed emphatically, from the common-used deformable models, such as the triangular affine transformation, the B-spline model, and the Thin Plate Spline (TPS), to some improved models proposed recently, such as the Quasi-Spherical Triangle (QST) model, the overlapping TPS model, and the Triangular Radial Cubic Spline (TRCS) model. This book includes Reconstruction techniques based on machine learning, statistical deformable modeling using principal component analysis, and Deep-learning methods for deformable surface reconstruction with selected experimental results.
