摘要
为了解决星敏感器星点质心定位中对过曝光星象的聚心问题,提出一种通用的星象聚心算法。采用先对局部星象区域进行初步计算,进而通过整体复合实现对所有星象的质心定位。首先,结合实拍星图介绍了想象的过曝光星象存在及区域分布;在分析其分布特性的基础上检测各行/列的过曝光区域尺度,根据与尺度相关的规则对相应点的灰度值进行空间缩放;然后利用质心平方加权法对缩放后的点值进行计算,得出局域的初步结果;进而结合过曝光区域的尺度对相应初步计算结果分配权值因子;最后,对全部结果进行复合得到最终结果。实验结果表明,采用提出的算法在全随机模拟情况下,当随机噪声强度达到30pixel时,对星象的聚心精度依然优于0.05pixel,能够满足实际应用中对聚心算法的精度和适应的要求。
In order to solve the centroiding problem of an over exposed star in star image processing,a universal centroiding algorithm was proposed with ＂first local calculation and then comprehensive integration＂.First,the existence of the over exposure stars was confirmed with real star images.Then,by analyzing the grey distribution of over exposed stars,the over-exposure scale of every row/column was detected according to the corresponding grey value and the square weighted mass centroiding was applied to calculation of primary local results.Finally,an over-exposure scale related to scaling scheme was used again to decide corresponding weights of local results and the final result was obtained after a last integration.The simulation results prove that in an all-random experiment mode the final centroiding accuracy has be better than 0.05 pixel even the random noise is 30 pixel.The proposed algorithm is validated to be competent and could satisfy the demand of the centroiding algorithm for the high-accuracy and good adaptability in real applications.
出处
《光学精密工程》
EI
CAS
CSCD
北大核心
2011年第10期2494-2499,共6页
Optics and Precision Engineering
基金
国家863高技术研究发展计划资助项目(No.2008AA7050411)
关键词
星敏感器
星点聚心
过曝光区域检测
点值缩放
变权重复合
star sensor
star centroiding
over-exposure detection
grey value scaling
variant weighted integration
