Stray light nonuniform background correction for a wide-field surveillance system.

ABSTRACT

Wide field and a long exposure time can effectively improve the ability of a space surveillance telescope to detect faint space targets. However, such systems are very susceptible to stray light. A stray light nonuniform background will cause great interference to subsequent target recognition, resulting in a large number of false alarms. This study presents an accurate and robust correction algorithm, called the improved new top-hat transformation (INTHT), for a stray light nonuniform background. First, we analyzed the formation mechanism and influence of the stray light nonuniform background. Then, to retrieve the lost targets, the size relationship of the two different, but related, structural operators is changed so the sizes of two structural operators are not equal. Finally, before comparing to the original image to take the minimum value, we added an expansion operation to restore the background size transformation caused by the different sizes of the structural operators in the previous step. This will ensure that there is no residual stray light nonuniform background. We believe, to the best of our knowledge, that the experimental results for the real captured image datasets demonstrate that, compared to other algorithms, the proposed INTHT algorithm has a higher accuracy and effectiveness in correcting a stray light nonuniform background.