Title
Calibration-Free Augmented Reality
Abstract
Camera calibration and the acquisition of Euclidean 3D measurements have so far been considered necessary requirements for overlaying three-dimensional graphical objects with live video. In this article, we describe a new approach to video-based augmented reality that avoids both requirements: It does not use any metric information about the calibration parameters of the camera or the 3D locations and dimensions of the environment's objects. The only requirement is the ability to track across frames at least four fiducial points that are specified by the user during system initialization and whose world coordinates are unknown.Our approach is based on the following observation: Given a set of four or more noncoplanar 3D points, the projection of all points in the set can be computed as a linear combination of the projections of just four of the points. We exploit this observation by 1) tracking regions and color fiducial points at frame rate, and 2) representing virtual objects in a non-Euclidean, affine frame of reference that allows their projection to be computed as a linear combination of the projection of the fiducial points. Experimental results on two augmented reality systems, one monitor-based and one head-mounted, demonstrate that the approach is readily implementable, imposes minimal computational and hardware requirements, and generates real-time and accurate video overlays even when the camera parameters vary dynamically.
Year
DOI
Venue
1998
10.1109/2945.675647
Visualization and Computer Graphics, IEEE Transactions
Keywords
Field
DocType
linear combination,color fiducial point,calibration,new approach,registration,calibration parameter,real-time computer vision,fiducial point,affine frame,camera parameter,augmented reality system,feature tracking,camera calibration,accurate video,3d interaction techniques,calibration-free augmented reality,index terms: augmented reality,affine representations,augmented reality,computer vision,indexing terms,frame of reference,real time systems,user interfaces,virtual reality
Affine transformation,Linear combination,Computer vision,Virtual reality,Computer graphics (images),Computer science,Image processing,Augmented reality,Camera resectioning,Frame rate,Artificial intelligence,Initialization
Journal
Volume
Issue
ISSN
4
1
1077-2626
Citations 
PageRank 
References 
67
5.64
51
Authors
2
Name
Order
Citations
PageRank
Kiriakos N. Kutulakos11801124.82
James R. Vallino2767.70