一种基于图像的星体表面撞击坑自动提取方法

以星体表面的图像数据为基础，根据撞击坑的向阳面呈亮色调而背阳面呈暗色调的原理，提出了一种基于图像的星体表面撞击坑自动提取方法。该方法先用自适应双阈值分割法对星体表面的光学图像进行分割处理，获取图像中明暗区域的形状和位置信息；再用统计学原理分析明暗区域组成结构、像平面上光照方向，结合相关的约束条件来匹配同一撞击坑的明暗区域，同时拟合出撞击坑的外边缘并确定其半径、位置等信息。实验结果表明，该方法能够从常见的星体表面光学图像中快速、可靠地提取出撞击坑的中心位置和半径大小，具有较宽的普适应性和一定的应用价值。

A Planetary Image Based Automatic Impact Crater Extraction Method

In this paper, a methodology for automatically extracting impact craters from planet surface based on image data is presented according to that the sunny side of crater is bright and the back side is dark. In the instance, the optical image from the planet surface is segmented by using the adaptive double threshold segmentation method, and both shape and position information of light and shade area in the image are obtained. Then, the structures of light and shade areas are analyzed according to the principle of statistics, and the direction of illumination is estimated in image-plane coordinate system. Combined with correlated constraint conditions, light and shade areas from same crater are matched, the external edge of the impact crater is fitted, and at the same time, the information of radius and position are obtained. The experiment results show that the method can be used to quickly and reliably extract both center position and radius of impact craters from planetary optical image, and it has wide adaptability and some certain application value.