两种快速星像匹配算法的比较

Comparison of Two Fast Object Matching Algorithms

星像的位置和亮度等信息对天文研究和空间导航具有基础意义。人们常常需要快速匹配从密集星场CCD图像中提取的信息来获取与星表中对应的信息(如位置、光度等),因此开发出了多种星像匹配算法。重点比较了两种最新的星像匹配算法:i)基于向量的方法;ii)基于径向和环向特征的方法。通过对云南天文台1m望远镜观测的CCD图像进行实际匹配,结果表明基于向量的方法更优,它是一种快速的、接近常数时间的匹配算法。

Positions and magnitudes of stars are important to astronomical researches and space navigations. The data （ such as those for position and brightness） extracted from CCD images of a dense star field usually need to be fast matched to a stellar catalog. A variety of object matching algorithms have been developed. In this paper, we compare two most recent matching algorithms： i） a method based on （positional） vectors; ii a method based on quantitative characteristics of relative stellar positions as described by the radii and circumferential directions from a chosen center. Through matching the CCD images taken with the 1 m telescope of the Yunnan Observatory , we find that the method based on vectors is faster and is thus practically more effective.