Results 221 to 230 of about 12,897 (254)

The Geometry of Colorful, Lenticular Fiducial Markers

2015 International Conference on 3D Vision, 2015
Understanding the pose of an object is fundamental to a variety of visual tasks, from trajectory estimation of UAVs to object tracking for augmented reality. Fiducial markers are visual targets designed to simplify this process by being easy to detect, recognize, and track. They are often based on features that are partially invariant to lighting, pose
Ian Schillebeeckx, Joshua Little, Brendan Kelly, Robert Pless   +3 more
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High-accuracy fiducial markers for ground truth

2016 International Conference on Image and Vision Computing New Zealand (IVCNZ), 2016
This paper introduces a fiducial marker which favours accuracy over run-time performance. Its intended use is for creating ground truth for outdoor SLAM in GPS-denied environments. Rather than using only corners or edges for pose estimation, the marker has a radial sinusoid pattern which has a predictable appearance under perspective projection.
Matthew J. Edwards, Michael P. Hayes, Richard D. Green   +2 more
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Designing Highly Reliable Fiducial Markers

IEEE Transactions on Pattern Analysis and Machine Intelligence, 2010
Fiducial markers are artificial landmarks added to a scene to facilitate locating point correspondences between images, or between images and a known model. Reliable fiducials solve the interest point detection and matching problems when adding markers is convenient. The proper design of fiducials and the associated computer vision algorithms to detect
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Edible fiducial marker made of edible retroreflector

Computers & Graphics, 2018
Abstract In Augmented Reality (AR) and Mixed Reality (MR), it is important to measure the position and orientation of objects in the real world. However, there were many difficulties in recognizing objects from images along, especially considering real-time processing.
Hiromasa Oku, Takahiro Uji, Yiting Zhang, Kumi Shibahara   +3 more
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Robust identification of fiducial markers in challenging conditions

Expert Systems with Applications, 2018
This work tackles the marker identification process as a classification problem.Methodology proposed to train the classifiers with a synthetic dataset of markers.Our proposal can identify markers under very difficult image conditions.The proposed method performs significantly better than previous approaches.
Víctor Manuel Mondéjar-Guerra, Sergio Garrido-Jurado, Rafael Muñoz-Salinas, Manuel J. Marín-Jiménez, Rafael Medina Carnicer   +4 more
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Endoscopic Ultrasound-Guided Fiducial Markers and Brachytherapy

Gastrointestinal Endoscopy Clinics of North America, 2012
Endoscopic ultrasound (EUS)-guided needle placement of small radiopaque particles paves the way for EUS-guided fiducial markers and brachytherapy. Stereotactic body radiation therapy relies on image-guided radiation therapy (IGRT), permitting escalation of radiation dose to tumors while minimizing dose to normal tissues. Fiducial markers are radiopaque
Zhendong, Jin, Kenneth J, Chang
openaire   +2 more sources

Fiducial Marker Placement for Intraoperative Spine Localization

Journal of Vascular and Interventional Radiology, 2011
In recent years, there has been a great increase in the number of cases of image-guided fiducial marker placement for the purposes of stereotactic radiosurgery. At the authors' parent institution, a tertiary referral academic medical center, the placement of fiducial markers has also been used for the purposes of localization before spine surgery ...
Daniel A, Marichal, David W, Barnett, James D, Meler, Kennith F, Layton   +3 more
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Fiducial Markers for Image Guided Partial Breast Irradiation

International Journal of Radiation Oncology*Biology*Physics, 2012
This study was undertaken to study the role of fiducial markers for image-guided partial breast irradiation (IG-PBI), and to compare the shifts based on bony anatomy and fiducial markers.Fifteen patients underwent IGPBI. Three fiducial markers were placed in the tumour bed at the time of surgery.
Marco, Trovo, Jerry, Polesel, Cristina, Biasutti, Giovanna, Sartor, Mario, Roncadin, Gaetano Mauro, Trovo   +5 more
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Augmented reality without fiducial markers

2015 20th Symposium on Signal Processing, Images and Computer Vision (STSIVA), 2015
This work presents an implementation of an augmented reality system that does not use fiducial markers for neither estimating the camera pose nor inserting a virtual object but natural marks such as corners of objects that are present in the scene. The system uses a RGB-D dataset for positioning the camera which moves with 6 DOF, for defining a work ...
Andres Diaz, Sebastian Caicedo, Eduardo Caicedo   +2 more
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Optimization Model for the Distribution of Fiducial Markers in Liver Intervention

Journal of Medical Systems, 2020
The distribution of fiducial markers is one of the main factors affected the accuracy of optical navigation system. However, many studies have been focused on improving the fiducial registration accuracy or the target registration accuracy, but few solutions involve optimization model for the distribution of fiducial markers.
Qinyong Lin, Rongqian Yang, Lin Yang, Huazhou Chen, Bohan Li 0001, Ken Cai   +5 more
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