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Journal of the Optical Society of America A

Journal of the Optical Society of America A

| OPTICS, IMAGE SCIENCE, AND VISION

  • Editor: Stephen A. Burns
  • Vol. 25, Iss. 1 — Jan. 1, 2008
  • pp: 29–39

Development of a sky imager for cloud cover assessment

A. Cazorla, F. J. Olmo, and L. Alados-Arboledas  »View Author Affiliations


JOSA A, Vol. 25, Issue 1, pp. 29-39 (2008)
http://dx.doi.org/10.1364/JOSAA.25.000029


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Abstract

Based on a CCD camera, we have developed an in-house sky imager system for the purpose of cloud cover estimation and characterization. The system captures a multispectral image every 5 min , and the analysis is done with a method based on an optimized neural network classification procedure and a genetic algorithm. The method discriminates between clear sky and two cloud classes: opaque and thin clouds. It also divides the image into sectors and finds the percentage of clouds in those different regions. We have validated the classification algorithm on two levels: image level, using the cloud observations included in the METAR register performed at the closest meteorological station, and pixel level, determining whether the final classification is correct.

© 2008 Optical Society of America

OCIS Codes
(010.1290) Atmospheric and oceanic optics : Atmospheric optics
(010.3920) Atmospheric and oceanic optics : Meteorology
(100.5010) Image processing : Pattern recognition
(120.0280) Instrumentation, measurement, and metrology : Remote sensing and sensors
(150.0150) Machine vision : Machine vision
(200.4260) Optics in computing : Neural networks

ToC Category:
Atmospheric and oceanic optics

History
Original Manuscript: June 22, 2007
Revised Manuscript: October 16, 2007
Manuscript Accepted: October 17, 2007
Published: December 5, 2007

Citation
A. Cazorla, F. J. Olmo, and L. Alados-Arboledas, "Development of a sky imager for cloud cover assessment," J. Opt. Soc. Am. A 25, 29-39 (2008)
http://www.opticsinfobase.org/josaa/abstract.cfm?URI=josaa-25-1-29


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