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Fast Algorithms for Matching CCD Images to a Stellar Catalogue

Published online by Cambridge University Press:  05 March 2013

V. Tabur
V. Tabur*
Affiliation:
School of Physics A28, University of Sydney, NSW 2006, Australia. Email: tabur@physics.usyd.edu.au
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Abstract

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Two new algorithms are described for matching two dimensional coordinate lists of point sources that are significantly faster than previous methods. By matching rarely occurring triangles (or more complex shapes) in the two lists, and by ordering searches by decreasing probability of success, it is demonstrated that very few candidates need be considered to find a successful match. Moreover, by immediately testing the suitability of a potential match using an efficient mechanism, the need to process the entire candidate set is avoided, yielding considerable performance improvements. Triangles are described by a cosine metric that reduces the density of triangle space, permitting efficient searches. An alternative shape characterization method that reduces computational overhead in the construction phase is discussed. The algorithms are tested on a set of 10 063 wide-field survey images, with fields-of-view up to 4.8° × 3.6°, successfully matching 100% of the images in a mean elapsed time of 6 ms (2.4 GHz Athlon CPU). The elapsed time of the searching phase is shown to vary by less than 1ms for list sizes between 10 and 200 points, demonstrating that fast, robust searches may be completed in nearly constant time, independent of list size.

Keywords

astrometrymethods: data analysissurveys
Type
Research Article
Information
Publications of the Astronomical Society of Australia , Volume 24 , Issue 4 , 2007 , pp. 189 - 198
Copyright
Copyright © Astronomical Society of Australia 2007

References

Arzoumanian, Z., Holmberg, J. & Norman, B., 2005, Journal of Applied Ecology, 42, 999 CrossRefGoogle Scholar
Edberg, S. J., 1983, International Halley Watch Amateur Observers' Manual for Scientific Comet Studies (Jet Propulsion Lab., California Inst. of Technology)Google Scholar
Everett, M. E. & Howell, S. B., 2001, PASP, 113, 1428 CrossRefGoogle Scholar
Fraser, B. J., 2003, SSRv, 107, 303 Google Scholar
Groth, E. J., 1986, AJ, 91, 1244 Google Scholar
Keller, S. C., et al., 2007, PASA, 24, 1 Google Scholar
Lasker, B. M., Sturch, C. R., McLean, B. J., Russell, J. L., Jenkner, H. & Shara, M. M., 1990, AJ, 99, 2019 CrossRefGoogle Scholar
Marsden, B. G., 1982, S&T, 64, 284 Google Scholar
Marszalek, M. & Rokita, P., 2004, Computer Vision and Graphics (Springer), 32, 1002 Google Scholar
Meeus, J., 1991, Astronomical Algorithms (Richmond, VA: Willmann-Bell)Google Scholar
Murtagh, F., 1992, PASP, 104, 301 CrossRefGoogle Scholar
Pál, A. & Bakos, G. Á., 2006, PASP, 118, 1474 Google Scholar
Rawat, S., Pujari, A. K., Gulati, V. P. & Vemuri, V. R., 2004, International Journal of Information Security (Springer–Verlag)Google Scholar
Stetson, P. B., 1990, The Techniques of Least Squares and Stellar Photometry with CCDs, http://nedwww.ipac.caltech.edu/level5/Stetson/Stetson5_2.html Google Scholar
Valdes, F. G., Campusano, L. E., Velásquez, J. D. & Stetson, P. B., 1995, PASP, 107, 1119 CrossRefGoogle Scholar