@ARTICLE{, author = {}, title = {A novel algorithm in thresholding, clustering and precise centroiding of night sky stars images }, volume = {11}, number = {1}, abstract ={In this paper a novel night sky star pattern recognition and precise centroiding approaches are proposed. Precision and computation time of image processing algorithm paly a great role in spacecraft in which the night sky star images are utilized for attitude determination. Star pattern recognition and centroiding are the most important steps of image processing algorithm in such attitude determination techniques. Here, in order to improve the computation time and precision of the image processing algorithm, a novel star pattern recognition approach including thresholding and clustering steps and precise centroiding method are proposed. Implementation results indicate that the proposed thresholding approach performs better than traditional approaches in dealing with images with uneven illumination. Lower computational burden and average centroiding error of less than 0.045 pixel obtained from experimenting 100 test simulated images, show the great capability of proposed image processing algorithm. }, URL = {http://jsdp.rcisp.ac.ir/article-1-131-en.html}, eprint = {http://jsdp.rcisp.ac.ir/article-1-131-en.pdf}, journal = {Signal and Data Processing}, doi = {}, year = {2014} }