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Point-less calibration: Camera parameters from gradient-based alignment to edge images

Peter Carr, Yaser Sheikh, Iain Matthews
2012 2012 IEEE Workshop on the Applications of Computer Vision (WACV)  
Overhead schematics of many environments resemble edge images. Edge images are difficult to align using image-based algorithms because both the image and its gradient are sparse.  ...  As a result, we are able to calibrate our camera models robustly using regular gradient-based image alignment, given an initial ground to image homography estimate.  ...  Previous Work Image-Based Calibration Image-based calibration estimates camera parameters directly from pixel intensities.  ... 
doi:10.1109/wacv.2012.6163012 dblp:conf/wacv/CarrSM12 fatcat:xn5pocy3j5e6bbdgywqis2w3ki

Deep Learning based Virtual Point Tracking for Real-Time Target-less Dynamic Displacement Measurement in Railway Applications [article]

Dachuan Shi, Eldar Sabanovic, Luca Rizzetto, Viktor Skrickij, Roberto Oliverio, Nadia Kaviani, Yunguang Ye, Gintautas Bureika, Stefano Ricci, Markus Hecht
2021 arXiv   pre-print
based rule engine for point tracking in adjacent frames.  ...  In the case that the optical target cannot be attached to the measuring objective, edge detection, feature matching and template matching are the most common approaches in target-less photogrammetry.  ...  Therefore, we combine a DL-based point detector with a domain-knowledge-based tracker to achieve real-time point tracking, which requires much less training data.  ... 
arXiv:2101.06702v3 fatcat:bjep4caf5rb4leeaqqkxcczgre

Multi-FEAT: Multi-Feature Edge AlignmenT for Targetless Camera-LiDAR Calibration [article]

Bichi Zhang, Raj Thilak Rajan
2022 arXiv   pre-print
This paper introduces a novel approach for targetless camera-LiDAR extrinsic calibration called Multi-FEAT (Multi-Feature Edge AlignmenT).  ...  Multi-FEAT uses the cylindrical projection model to transform the 2D(Camera)-3D(LiDAR) calibration problem into a 2D-2D calibration problem, and exploits various LiDAR feature information to supplement  ...  eliminating the low-quality edges influenced by the occlusion effect. • A cost function is designed to align the edge intensities of the camera images' edge probability acquired from the multi-feature  ... 
arXiv:2207.07228v1 fatcat:4ixut45uuje65cw5psg7wzd5eq

Calibrating Distributed Camera Networks

D. Devarajan, Zhaolin Cheng, R.J. Radke
2008 Proceedings of the IEEE  
We next describe a distributed algorithm in which each camera performs a local, robust nonlinear optimization over the camera parameters and scene points of its vision graph neighbors to obtain an initial  ...  In particular, we discuss a decentralized method for obtaining the vision graph for a distributed camera network, in which each edge of the graph represents two cameras that image a sufficiently large  ...  Once the vision graph is established, false edges can be removed based on further messages (e.g., moving from the circular to the square operating point).(Figure from [7] .)  ... 
doi:10.1109/jproc.2008.928759 fatcat:tig2sqoz6ngtnbwfgl3hnuu7q4

Motion Guided LIDAR-camera Self-calibration and Accelerated Depth Upsampling for Autonomous Vehicles [article]

Juan Castorena and Gint Puskorius and Gaurav Pandey
2020 arXiv   pre-print
This work proposes a novel motion guided method for target-less self-calibration of a LiDAR and camera and use the re-projection of LiDAR points onto the image reference frame for real-time depth upsampling  ...  The calibration parameters are estimated by optimizing an objective function that penalizes distances between 2D and re-projected 3D motion vectors obtained from time-synchronized image and point cloud  ...  uses the image in 7.a from the camera.  ... 
arXiv:1803.10681v3 fatcat:barn3grkjrgv7cg52zrkqknaau

Joint Camera Intrinsic and LiDAR-Camera Extrinsic Calibration [article]

Guohang Yan, Feiyu He, Chunlei Shi, Xinyu Cai, Yikang Li
2022 arXiv   pre-print
To this end, we propose a novel target-based joint calibration method of the camera intrinsic and LiDAR-camera extrinsic parameters.  ...  parameter calibration is often reduced due to the tiny error of the camera's intrinsic parameters.  ...  The calibration goal is to align the LiDAR point cloud with the camera image through intrinsic and extrinsic parameters.  ... 
arXiv:2202.13708v2 fatcat:oumnzfn5lrefrlrtpiafxdwcwm

Targetless Extrinsic Calibration of Stereo Cameras, Thermal Cameras, and Laser Sensors in the Wild [article]

Taimeng Fu, Huai Yu, Wen Yang, Yaoyu Hu, Sebastian Scherer
2022 arXiv   pre-print
alignment of the edge features.  ...  However, such calibration is difficult due to the variety of sensor modalities and the requirement of calibration targets and human labor.  ...  ACKNOWLEDGEMENT The authors acknowledge the sponsorship of this work from the Shimizu Institute of Technology (Tokyo).  ... 
arXiv:2109.13414v2 fatcat:woizglvawrcfdgwdd6qqswq2za

Targetless Camera-LiDAR Calibration in Unstructured Environments

Miguel A. MunoznBanon, Francisco A. Candelas, Fernando Torres
2020 IEEE Access  
This method consists of a novel co-registration approach that uses local edge features in arbitrary environments to get 3D-to-2D errors between the data of both, camera and LiDAR.  ...  In this article, we present a novel calibration method that achieves an accurate six-degree-offreedom (6-DOF) rigid-body transformation estimation (aka extrinsic parameters) between the camera and LiDAR  ...  CO-REGISTRATION OF CAMERA-LIDAR POINTS To perform edge alignment at the object level, we do a clustering at D points, first in the depth dimension, and then, in two dimensions of the image plane.  ... 
doi:10.1109/access.2020.3014121 fatcat:gm6bjp7odra7pmd3ynziloawqq

Sports Camera Calibration via Synthetic Data [article]

Jianhui Chen, James J. Little
2018 arXiv   pre-print
The camera pose engine has only three significant free parameters so that it can effectively generate a lot of camera poses and corresponding edge (i.e, field marking) images.  ...  Here we propose a highly automatic method for calibrating sports cameras from a single image using synthetic data. First, we develop a novel camera pose engine.  ...  Our method is significantly different from this method in two points. First, we propose a novel camera pose engine to generate edge images.  ... 
arXiv:1810.10658v1 fatcat:o7i7fv3fgnb3fi4ux6u54h2ksa

A Novel Calibration Board and Experiments for 3D LiDAR and Camera Calibration

Huaiyu Cai, Weisong Pang, Xiaodong Chen, Yi Wang, Haolin Liang
2020 Sensors  
In addition, the "three-step fitting interpolation method" was proposed to select feature points and obtain the corresponding coordinates of feature points in the LiDAR coordinate system and camera pixel  ...  Aiming at the problems of feature point calibration method of 3D light detection and ranging (LiDAR) and camera calibration that are calibration boards in various forms, incomplete information extraction  ...  [9] used the natural alignment of depth and intensity edges in combination with a Gaussian mixture model to solve the calibration result.  ... 
doi:10.3390/s20041130 pmid:32092995 pmcid:PMC7070607 fatcat:sav6zkxbpzg2havcy6hesnxqwm

Radiometric Calibration [chapter]

Yasuyuki Matsushita
2014 Computer Vision  
We present a robust radiometric calibration framework that capitalizes on the transform invariant low-rank structure in the various types of observations, such as sensor irradiances recorded from a static  ...  scene with different exposure times, or linear structure of irradiance color mixtures around edges.  ...  Fig. 9 . 9 Results of our calibration method with a dataset captured from a Point Grey Flea3 camera. Fig. 10 . 10 Radiometric alignment of real-world images.  ... 
doi:10.1007/978-0-387-31439-6_522 fatcat:utlwuopngvbgncudydsfox26sy

Sports Camera Calibration via Synthetic Data

Jianhui Chen, James J. Little
2019 2019 IEEE/CVF Conference on Computer Vision and Pattern Recognition Workshops (CVPRW)  
Here we propose a highly automatic method for calibrating sports cameras from a single image using synthetic data.  ...  The camera pose engine has only three significant free parameters so that it can effectively generate diverse camera poses and corresponding edge (i.e. field marking) images.  ...  Our method extends the two-point method [6] which requires prior knowledge of camera base location and orientation to calibrate pan-tilt-zoom (PTZ) cameras.  ... 
doi:10.1109/cvprw.2019.00305 dblp:conf/cvpr/ChenL19 fatcat:sh54ura6g5gsdcghnnepseehia

Automatic detection of calibration grids in time-of-flight images

Miles Hansard, Radu Horaud, Michel Amat, Georgios Evangelidis
2014 Computer Vision and Image Understanding  
It is convenient to calibrate time-of-flight cameras by established methods, using images of a chequerboard pattern.  ...  The proposed Hough-based method is compared to the standard OpenCV detection routine, by application to several hundred time-of-flight images.  ...  It makes use of the gradient orientation as well as magnitude at each point, in order to establish an axis-aligned coordinate system for each image of the pattern.  ... 
doi:10.1016/j.cviu.2014.01.007 fatcat:7sbjq3l2hrge3bu5ck7tsigcze

Auto-calibration Method Using Stop Signs for Urban Autonomous Driving Applications [article]

Yunhai Han, Yuhan Liu, David Paz, Henrik Christensen
2021 arXiv   pre-print
The approach is based on detection, geometry estimation, calibration, and recursive updating. Results from natural environments are presented that clearly show convergence and improved performance.  ...  An approach based on recognition of traffic signs, such as stop signs, and use of them for recalibration of cameras is presented.  ...  RELATED WORK Camera Calibration: Camera parameters can be estimated from enough pairs of 3D object points and corresponding 2D image points [11] .  ... 
arXiv:2010.07441v2 fatcat:k7bjs2soavekbmhp5dtylmeuge

Automatic calibration of multi-modal sensor systems using a gradient orientation measure

Zachary Taylor, Juan Nieto, David Johnson
2013 2013 IEEE/RSJ International Conference on Intelligent Robots and Systems  
A novel technique for calibrating a multi-modal sensor system has been developed. Our calibration method is based on the comparative alignment of output gradients from two candidate sensors.  ...  The algorithm is applied to the calibration of the extrinsic parameters of several camera-lidar systems. In this calibration the lidar scan is projected onto the camera's image using a camera model.  ...  Camera model To convert the lidar data from a list of 3-D points to a 2-D image that can be compared to the camera's images, the points are first passed into a transformation matrix that aligns the camera's  ... 
doi:10.1109/iros.2013.6696516 dblp:conf/iros/TaylorNJ13 fatcat:o2ugsfobnrdi5gf465ummkb7j4
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