Title
Geo-Referencing And Stereo Calibration Of Ground-Based Whole Sky Imagers Using The Sun Trajectory
Abstract
Ground-based Whole Sky Imagers (WSIs) are now commonly used for cloud observations. Upon deployment, they may not be exactly level or precisely face north. This significantly affects subsequent processing of the images, especially for applications where two or more imagers are required, e.g. 3D volumetric cloud reconstruction.We present a method to remove this mis-alignment using the sun position in images captured over a whole day. Coupled with precise coordinates of the device locations, this method also improves the geo-referencing accuracy of the captured images. We detect the sun in the images and compute the corresponding 3D vectors using the lens calibration function. These vectors are compared to the actual sun direction. The mismatch between the two sets of vectors is then corrected using a 3D rotation matrix. The method can also be applied to other celestial bodies, such as stars or the moon.
Year
DOI
Venue
2016
10.1109/IGARSS.2016.7730949
2016 IEEE INTERNATIONAL GEOSCIENCE AND REMOTE SENSING SYMPOSIUM (IGARSS)
Keywords
Field
DocType
WAHRSIS, ground-based sky camera, Whole Sky Imager (WSI), stereo calibration, geo-referencing
Computer vision,Rotation matrix,Stars,Computer science,Remote sensing,Sky,Artificial intelligence,Geo referencing,Image resolution,Trajectory,Calibration,Cloud computing
Conference
ISSN
Citations 
PageRank 
2153-6996
2
0.52
References 
Authors
4
4
Name
Order
Citations
PageRank
Florian M. Savoy1224.62
Soumyabrata Dev26213.94
Yee Hui Lee310724.09
Stefan Winkler421621.60