基于规范化线性滤波器的漂移扫描恒星抑制

Suppression of drift-scanning star based on standardized linear filter

针对漂移扫描星图中大量恒星星像对小目标检测产生干扰的问题,提出了一种自适应的线性滤波方法,通过抑制恒星星像实现对小目标的检测。首先,在分析恒星、感兴趣目标和噪声三者特征的基础上,构造规范化线性滤波器对星图进行滤波,扩大不同亮度恒星和小目标星像的灰度对比度,并构造梯度线性滤波器自适应地抑制恒星星像。其次,通过理论分析,给出了滤波器参数的选择策略。最后,比较不同方法对实际数据处理的实验结果,表明所提方法对不同长度和倾斜角度的恒星星像都具有较好的抑制效果,易于应用实现。

A large number of stars in the drift-scanning star image interfer with the detection of small targets.An adaptive linear filtering method is proposed to achieve the small target detection by suppressing the stars.Firstly,the characteristics of three different representative objects,i.e.,stars,interest targets and noise,in the star image are analyzed,then the standardized linear filter is constructed to filter the drift-scanning star image so as to achieve the gray value amplification of different stars with the reduction of small targets.Meantime,for the purpose of suppressing the stars adaptively,a gradient linear filter is constructed to modify the effect with the standardized linear filter.The residual processing between the original star image and final filtering result suppresses the drift-scanning stars.Secondly,theoretical analysis is done to give the filter parameter selection strategy.Finally,with the processing results of different methods on the real drift-scanning data,it is shown that the proposed method for suppressing stars with different lengths and lean angles has a better effect and easier application than the others.