基于能量分布的星点提取方法

为提高星图预处理中质心提取的精度和实时性,提出了一种基于星点能量分布的星点提取方法.该方法将星点的能量分布概括为如下三个特点：一是当σ＜0.671时,星点的能量主要集中在其中心3×3像元的区域内;二是星点中心灰度最大;三是星点中心周围8个像元的灰度值大于平均灰度值.依据后两个特点可以确定星点中心像元,然后根据第一个特点就可以用传统的质心算法对星点中心3×3区域进行质心提取.仿真结果表明,该方法能够实时有效地进行星点提取,且实时性优于连通域法,在星等小于5时质心提取精度也要优于连通域法.

A method of star extraction based on the energy distribution of the star point

To improve the real-time and the accuracy of centroid extraction in star image processing step, according to the energy distribution of the star point, a novel method of star extraction is presented. This method generalizes the characteristics of energy distribution of star point as follows： When σ 〈 0. 671, the energy of star point is mainly concentrated in the 3 × 3 region around the center pixel;The center of star point has the largest gray scale ; The gray scale of the 8 pixels which around the center pixel are larger than the average gray scale. The center of the star point can be determined based on the latter two features, then according to the first characteristic, the traditional centroid algorithm can be used to achieve the centroid extraction for the 3 × 3 region around the center pixel. The simulation results show that it is an effective method and the real-time of it is better than the connected domain method, when the star magnitude is less than 5, the accuracy of centroid extraction can also be better than the connected domain method.