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Related papers: Auto-Calibration of Cone Beam Geometries from Arbi…

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This work is concerned with fan- and cone-beam computed tomography with circular source trajectory, where the reconstruction inverse problem requires an accurate knowledge of source, detector and rotational axis relative positions and…

Numerical Analysis · Mathematics 2024-05-09 Patricio Guerrero , Simon Bellens , Ricardo Santander , Wim Dewulf

For cone-beam three-dimensional computed tomography (3D-CT) scanning system, voxel size is an important indicator to guarantee the accuracy of data analysis and feature measurement based on 3D-CT images. Meanwhile, the voxel size changes…

Instrumentation and Detectors · Physics 2015-06-15 Min Yang , Xiaolong Wang , Yipeng Liu , Fanyong Men , Xingdong Li , Wenli Liu , Dongbo Wei

Computed tomography is a method for synthesizing volumetric or cross-sectional images of an object from a collection of projections. Popular reconstruction methods for computed tomography are based on idealized models and assumptions that…

Numerical Analysis · Mathematics 2022-03-03 Frederik H. Pedersen , Jakob S. Jørgensen , Martin S. Andersen

We propose a method to achieve the geometric calibration of cone-beam imaging and delivery systems in radiation therapy; our approach applies to devices where an X-ray source and a flat-panel detector, facing each other, move in circular…

Medical Physics · Physics 2007-05-23 Evangelos Matsinos , Wolfgang Kaissl

Planar markers are useful in robotics and computer vision for mapping and localisation. Given a detected marker in an image, a frequent task is to estimate the 6DOF pose of the marker relative to the camera, which is an instance of planar…

Computer Vision and Pattern Recognition · Computer Science 2019-09-27 Shin-Fang Ch'ng , Naoya Sogi , Pulak Purkait , Tat-Jun Chin , Kazuhiro Fukui

Industrial cone-beam X-ray computed tomography (CT) scans of additively manufactured components produce a 3D reconstruction from projection measurements acquired at multiple predetermined rotation angles of the component about a single…

Image and Video Processing · Electrical Eng. & Systems 2024-07-19 Jingsong Lin , Singanallur Venkatakrishnan , Gregery Buzzard , Amir Koushyar Ziabari , Charles Bouman

In computer graphics, the field of view of a camera is represented by a viewing frustum and a corresponding projection matrix, the properties of which, in the absence of restrictions on rectangular shape of the near plane and its…

Graphics · Computer Science 2021-05-21 Nikita Glushkov , Tyuleneva Emiliya

When a projection of a symmetric or Hermitian matrix to the positive semidefinite cone is computed approximately (or to working precision on a computer), a natural question is to quantify its accuracy. A straightforward bound invoking…

Numerical Analysis · Mathematics 2019-08-16 Paul J. Goulart , Yuji Nakatsukasa , Nikitas Rontsis

This paper addresses the problem of mirror surface reconstruction, and proposes a solution based on observing the reflections of a moving reference plane on the mirror surface. Unlike previous approaches which require tedious calibration,…

Computer Vision and Pattern Recognition · Computer Science 2021-01-26 Kai Han , Miaomiao Liu , Dirk Schnieders , Kwan-Yee K. Wong

Identification of model parameters in computer simulations is an important topic in computer experiments. We propose a new method, called the projected kernel calibration method, to estimate these model parameters. The proposed method is…

Methodology · Statistics 2017-05-10 Rui Tuo

We develop a Bayesian approach called Bayesian projected calibration to address the problem of calibrating an imperfect computer model using observational data from a complex physical system. The calibration parameter and the physical…

Methodology · Statistics 2019-02-08 Fangzheng Xie , Yanxun Xu

Iterative phase retrieval algorithms typically employ projections onto constraint subspaces to recover the unknown phases in the Fourier transform of an image, or, in the case of x-ray crystallography, the electron density of a molecule.…

Numerical Analysis · Mathematics 2025-10-20 Veit Elser

We are presenting a simple and numerical stable algorithm for the solution of the cone projection problem which is suitable for relative small data sets and for simulation purposes needed for convexity tests. Not even one pseudo-inverse…

Computation · Statistics 2012-07-12 Demetris T. Christopoulos

Geometric calibration of cameras and projectors is an essential step that must be performed before any imaging system can be used. There are many well-known geometric calibration methods for calibrating systems comprised of multiple…

Computer Vision and Pattern Recognition · Computer Science 2024-10-25 Tomislav Petkovic , Simone Gasparini , Tomislav Pribanic

Typical Structure-from-Motion (SfM) pipelines rely on finding correspondences across images, recovering the projective structure of the observed scene and upgrading it to a metric frame using camera self-calibration constraints. Solving…

Computer Vision and Pattern Recognition · Computer Science 2020-07-07 Rui Gong , Danda Pani Paudel , Ajad Chhatkuli , Luc Van Gool

The circumcentered-reflection method (CRM) has been applied for solving convex feasibility problems. CRM iterates by computing a circumcenter upon a composition of reflections with respect to convex sets. Since reflections are based on…

Optimization and Control · Mathematics 2022-01-05 Guilherme Araújo , Reza Arefidamghani , Roger Behling , Yunier Bello-Cruz , Alfredo Iusem , Luiz-Rafael Santos

We introduce a novel class of projectors for 3D cone beam tomographic reconstruction. Analytical formulas are derived to compute the relationship between the volume of a voxel projected onto a detector pixel and its contribution to the line…

Image and Video Processing · Electrical Eng. & Systems 2025-03-27 Vojtěch Kulvait , Julian Moosmann , Georg Rose

The structured light projection technique is a representative active method for 3-D reconstruction, but many researchers face challenges with the intricate projector calibration process. To address this complexity, we employs an additional…

Optics · Physics 2024-03-05 Seung-Jae Son , Yatong An , Jae-Sang Hyun

This paper develops a uniformly valid and asymptotically nonconservative test based on projection for a class of shape restrictions. The key insight we exploit is that these restrictions form convex cones, a simple and yet elegant structure…

Econometrics · Economics 2021-09-21 Zheng Fang , Juwon Seo

Most intelligent transportation systems use a combination of radar sensors and cameras for robust vehicle perception. The calibration of these heterogeneous sensor types in an automatic fashion during system operation is challenging due to…

Computer Vision and Pattern Recognition · Computer Science 2019-07-30 Christoph Schöller , Maximilian Schnettler , Annkathrin Krämmer , Gereon Hinz , Maida Bakovic , Müge Güzet , Alois Knoll
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