附加恒星视运动修正的白昼星图星点提取方法  

A method for star extraction from daytime star maps with additional correction of eastern elongation

作　　者：勾万祥 李崇辉[1] 佟帅 郑勇[1] 杨原 陈智兴 詹银虎[1] GOU Wanxiang;LI Chonghui;TONG Shuai;ZHENG Yong;YANG Yuan;CHEN Zhixing;ZHAN Yinhu(Information Engineering University,Zhengzhou 450000,China)

机构地区：[1]信息工程大学,河南郑州450000

出　　处：《测绘学报》2024年第11期2166-2177,共12页Acta Geodaetica et Cartographica Sinica

基　　金：国家自然科学基金(42374011,42074013);河南省优秀青年基金(242300421150,242300421151)。

摘　　要：白昼星图具有高背景噪声、低信噪比等特征,传统方法很难高效提取星点,且由于星点为弱小目标,对噪声极为敏感,成像随机不规则,单帧提取星点质心稳健性较差。为此,本文提出一种附加恒星视运动修正的星点提取方法,该方法首先根据测站、星历、观测时间预测恒星概略位置,通过相机参数转换模型得出星点在像平面坐标系中的概略位置;然后,利用各帧星图拍摄时刻精确计算出星点相对运动量,将各帧星图星点预测区域进行配准叠加;最后,在星点预测位置区域对星点进行精确提取。试验表明:该方法星点提取成功率可达100%,较传统算法提升163%以上,且算法执行效率高,耗时缩短至传统方法的23%;除此之外,多帧叠加增强了星图信噪比,克服了星点成像随机误差,星点质心提取精度较单帧星图提取方法提升72%以上。The daytime star map is characterized by high background noise and low signal-to-noise ratio,which lowers the efficiency of traditional star extraction methods.Moreover,robustness of single frame extraction methods is poor due to the negative factors of daytime star map,including star energy weakness,noise sensitivity and star contour irregularity.Therefore,a star extraction method with modification of apparent motion is proposed for daytime infrared star map processing.With application of camera parameter conversion model,image coordinates of the target star were predicted using the data of station position,observation time and ephemeris.Further,relative displacements of the star in image sequence were precisely calculated using the exposure intervals,which led to precise register of the image superposition on star area,and finally resulted to accurate star extraction.Experimental results show that the success rate of star extraction with the proposed method can reach 100%,which is 163%higher than that of traditional algorithms.Meanwhile,the time consumption was reduced to 23%.Signal-to-noise ratio was also enhanced since the influence of random error was greatly reduced,and the centroid extraction accuracy was improved by 72%compared to single frame methods.

关 键 词：白昼星图 视运动 星点提取 质心精度 天文大地测量 多帧叠加 

分 类 号：P222[天文地球—大地测量学与测量工程]