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Geometry-based Camera Calibration Using Closed-form Solution of Principal Line

Jen-Hui Chuang, Chih-Hui Ho, Ardian Umam, Hsin-Yi Chen, Jenq-Neng Hwang, Tai-An Chen
2021 IEEE Transactions on Image Processing  
in the computation and (ii) the assumption of fixed camera focal length.  ...  calibration pattern.  ...  focal length and (b) using different focal lengths in the image acquisition process.  ... 
doi:10.1109/tip.2020.3048684 pmid:33417556 fatcat:5zd4fxf37ncghntpcoxorh2rve

Calibration of Central Catadioptric Cameras Using a DLT-Like Approach

Luis Puig, Yalin Bastanlar, Peter Sturm, J. J. Guerrero, João Barreto
2010 International Journal of Computer Vision  
We show how to decompose it to obtain intrinsic and extrinsic parameters. Moreover, we use this parameter estimation followed by a non-linear optimization to calibrate various types of cameras.  ...  We are able to represent the projection of 3D points on a catadioptric image linearly with a 6×10 projection matrix, which uses lifted coordinates for image and 3D points.  ...  camera's focal length, the mirror parameters and the rotation between the camera and the mirror (R p ).  ... 
doi:10.1007/s11263-010-0411-1 fatcat:dchjaxhoxfc3bbdavfwwnca444

Geometry-based Camera Calibration Using Closed-form Solution of Principal Line

Jen-Hui Chuang, Chih-Hui Ho, Ardian Umam, Hsin-Yi Chen, Jenq-Neng Hwang, Tai-An Chen
2021 IEEE Transactions on Image Processing  
in the computation and (ii) the assumption of fixed camera focal length.  ...  calibration pattern.  ...  fixed focal length and (b) using different focal lengths in the image acquisition process.  ... 
doi:10.1109/tip.2020.3048684 fatcat:cz7snbmx7rgyxcjndvgs3n767m

Plane-based calibration of cameras with zoom variation

Chao Yu, Gaurav Sharma, John G. Apostolopoulos, Amir Said
2006 Visual Communications and Image Processing 2006  
These algorithms have the advantage of robustness compared to self-calibration and flexibility compared to traditional algorithms which require a 3D calibration pattern.  ...  The algorithm is tested using both synthetically generated images and actual images captured using a digital camera.  ...  We consider the case that extrinsic parameters such as rotation and translation are free to change.  ... 
doi:10.1117/12.650944 fatcat:gvgkrnwnlvc33ht772k5q4qiai

Determination of the Interior Orientation Parameters of a Non-metric Digital Camera for Terrestrial Photogrammetric Applications

Naa Dedei Tagoe, S. Mantey
2019 Ghana Mining Journal  
The camera parameters were obtained using the two software and the Root Mean Square Errors (RMSE) calculated.  ...  Photo Modeler and Australis) to calibrate a non-metric digital camera to determine its Interior Orientation Parameters.  ...  They are: focal length of the lens, principal point (centre), pixel size and distortion coefficients. The extrinsic parameters are: rotation and translation parameters (Fig. 3) .  ... 
doi:10.4314/gm.v19i2.1 fatcat:iuwvo55eqzbdtfltlthynzjxkq


A. Choinowski, D. Dahlke, I. Ernst, S. Pless, I. Rettig
2019 The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences  
Intrinsic parameters and spatial alignment are determined simultaneously. As calibration target a passive aluminium chessboard is used.  ...  </strong> This paper presents a system calibration method for a trifocal sensor, which is sensitive to different spectral bands.  ...  ACKNOWLEDGEMENTS The authors of this paper would like to thank Thomas Säuberlich and his team from the Department for Space Instruments at the German Aerospace Centre for providing the thermal imaging  ... 
doi:10.5194/isprs-archives-xlii-2-w13-1631-2019 fatcat:xq6gy5i6ovhkno7gkh77workcu

Camera calibration for miniature, low-cost, wide-angle imaging systems

O. Frank, R. Katz, C.-L. Tisse, H. Durrant-Whyte
2007 Procedings of the British Machine Vision Conference 2007  
This paper presents a new model and an extension to an existing algorithm for camera calibration.  ...  The main goal of the proposed approach is to calibrate miniature, low-cost, wide-angle fisheye lenses. The model has been verified with a calibration implementation and was tested on real data.  ...  Summary and Conclusion An extension to an existing calibration algorithm has been proposed in order to deal with miniature, low-cost, and wide-angle imaging systems.  ... 
doi:10.5244/c.21.31 dblp:conf/bmvc/FrankKTD07 fatcat:eun4dxs6hbe3lapsahyttu2cs4

Geometric calibration of Colour and Stereo Surface Imaging System of ESA's Trace Gas Orbiter

Stepan Tulyakov, Anton Ivanov, Nicolas Thomas, Victoria Roloff, Antoine Pommerol, Gabriele Cremonese, Thomas Weigel, Francois Fleuret
2018 Advances in Space Research  
There are many geometric calibration methods for "standard" cameras. These methods, however, cannot be used for the calibration of telescopes with large focal lengths and complex off-axis optics.  ...  We further encourage re-use of the proposed method by making our calibration code and data available on-line.  ...  Support from SGF (Budapest), the University of Arizona (Lunar and Planetary Lab.) and NASA are also gratefully acknowledged. We also acknowledge support from the NCCR PlanetS.  ... 
doi:10.1016/j.asr.2017.10.025 fatcat:up65olfvc5fvzj3jjktzinkmoe

Camera and light calibration from reflections on a sphere

Dirk Schnieders, Kwan-Yee K. Wong
2013 Computer Vision and Image Understanding  
Besides, given multiple views of the sphere, it will be shown that the focal length and the relative positions and orientations of the cameras can be determined using the recovered sphere and light directions  ...  This paper introduces a novel method for recovering light directions and camera parameters using a single sphere.  ...  The estimated focal lengths was again compared against estimates made using the planar calibration pattern. The experiment was repeated for different focal lengths.  ... 
doi:10.1016/j.cviu.2013.06.004 fatcat:tuduren6rjdhjnnb5s36nk2yyy

An LMI Approach for Reliable PTZ Camera Self-Calibration

Hongdong Li, Chunhua Shen
2006 2006 IEEE International Conference on Video and Signal Based Surveillance  
Traditional off-line camera calibration algorithms are often not satisfactory because some of the PTZ camera intrinsic parameters (e.g., focal length) may change during working.  ...  PTZ (Pan-Tilt-Zoom) cameras are widely used for large-area video surveillance. For many visual tracking and video analysis tasks, an accurate camera calibration is very important.  ...  Thank the second reviewer who suggested explaining more on the practical implication of the positive-definite condition, and removing confusing short-hands.  ... 
doi:10.1109/avss.2006.21 dblp:conf/avss/LiS06 fatcat:tm7kfbgj7bgljd5fd3zgvtx7lq

Towards Auto-calibration of Smart Phones Using Orientation Sensors

Philip Saponaro, Chandra Kambhamettu
2013 2013 IEEE Conference on Computer Vision and Pattern Recognition Workshops  
In this paper, we address the problem of auto calibration of cameras which can rotate freely and change focal length, and we present an algorithm for finding the intrinsic parameters using only two images  ...  Our results are comparable to other recent auto-calibration work while requiring only two images and being tolerant to some translation.  ...  Camera Calibration with Two Images -General Rotation and Changing Focal Length As in [13] , we need only two images to calibrate the camera.  ... 
doi:10.1109/cvprw.2013.8 dblp:conf/cvpr/SaponaroK13 fatcat:zfni7hobl5au7m22etvito6bzi

Simple calibration without metric information using an isoceles trapezoid

Xiaochun Cao, H. Foroosh
2004 Proceedings of the 17th International Conference on Pattern Recognition, 2004. ICPR 2004.  
By ultilizing the symmetry of such trapezoid, we show that one can obtain both the internal and the external camera parameters.  ...  Assuming a unit aspect ratio and zero skew, we introduce a novel and simple camera calibration approach.  ...  The estimated camera intrinsic and extrinsic parameters were then compared with the ground truth. For the rotation angles, we have shown the absolute errors of the 2 nd image in degrees.  ... 
doi:10.1109/icpr.2004.1334018 dblp:conf/icpr/CaoF04 fatcat:kjjzmefjsfcnzoj74n6v36nqze

Methods for geometrical video projector calibration

Jamil Draréni, Sébastien Roy, Peter Sturm
2011 Machine Vision and Applications  
Not using a printed pattern as most existing methods do is another gain in accuracy and ease of use.  ...  The first method assumes a partial knowledge on the camera parameters whereas the second method consists in an auto-calibration method with no assumption on the parameters of the camera.  ...  Reported parameters are focal length and principal point (u, v).  ... 
doi:10.1007/s00138-011-0322-3 fatcat:s24rfrvghvgtdgczodbt3w3bea

Behaviour of SFM algorithms with erroneous calibration

Loong-Fah Cheong, Xu Xiang
2011 Computer Vision and Image Understanding  
We demonstrate both analytically and in simulation how uncertainty in the calibration parameters gets propagated to motion estimates in a differential setting.  ...  In particular, we studied how erroneous focal length and principal point estimates affect the behavior of the bas-relief ambiguity and introduce additional biasing to the translation estimate in a non-simple  ...  variations even though the camera only changes its extrinsic pose relative to the calibration pattern.  ... 
doi:10.1016/j.cviu.2010.08.004 fatcat:d5dv2h4moncczlmdje3wuqdzom

Identification of stereo rig alignment error based on vertical disparity ma

Sandeep Katragadda
2019 Journal of WSCG  
In this work feature extraction techniques such as SIFT, SURF and Harris features are efficiently used to compute reliable and robust vertical disparity patterns.  ...  If the vertical disparity values are too small or ambiguous to be identified by pattern analysis, this paper uses graphical analysis that highlights the relationship between the total vertical disparity  ...  A stereo camera system is said to be calibrated if its intrinsic parameters and the extrinsic parameters are known.  ... 
doi:10.24132/jwscg.2019.27.2.8 fatcat:qfan7rftsffnfpakulnssmnbn4
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