摘要
提出空间碎片观测中对拖长背景恒星的测光算法,介绍了该方法的基本原理。利用迭代法对目标图像进行局部阈值分割提取,得到的二值图像通常包含多个连通域。最后对各连通域块检测判断,计算出目标的星等,达到测光的目的。通过与天文图像和数据处理软件IRAF的测光结果对比,此算法的误差在0.02mag左右,可以达到测光的要求。
A photometric method is presented to derive the magnitudes of stretched images of background stars from observations of space debris. The basic principle of this method is described. An iterative approach is introduced to obtain segments of the observed image, with each iteration severing a segment of image from the previous iteration further into two segments, where the pixel values are above and below a threshold, respectively （ --threshold segmentation）. The set of segments usually contains a sufficient amount of connected areas corresponding to the stretched image regions of background stars, so that these areas can be selected out based on their pixel values to yield the detection of stars. Magnitudes of stars can be calculated from these connected areas. The error of this algorithm is approximately 0. 02 mag, according to the comparison to the photometry with the IRAF（ Image Reduction and Analysis Facility）.
出处
《天文研究与技术》
CSCD
2009年第1期20-23,共4页
Astronomical Research & Technology
关键词
天体测光学
星等
高斯滤波掩模
阈值分割
Astronomical photometry
magnitude
Gaussion filter mask
threshold segmentation
