Restoration of motion-blurred star images with elliptical star streaks

The restoration of motion-blurred star images under high dynamic conditions is important for the high-precision attitude measurement of star sensors. Through motion modelling analysis, it is found that the streak of the imaged star point (star streak) is an elliptical arc. However, existing star image restoration methods are only suitable for the case where the star streak is a straight line. For this reason, a star image restoration algorithm for elliptical star streaks is proposed in this paper. First, the elliptical star streak is transformed into a circular star streak by projective transformation. Then, the circular star streak is transformed into a straight star streak by polar coordinate transformation. Finally, the restored original star image is obtained by restoration methods for straight star streaks and coordinate inverse transformation. At the same time, the algorithm is further optimized by subdividing the polar coordinates. The experiment shows that the proposed algorithm is effective and the restoration accuracy is at the same level as that of existing star image restoration methods for straight star streaks.