With the increasing of the imaging resolution of remote sensing satellites in the future, their coverage range will become wider and wider and their observation data will increase greatly. The existing manual monitoring is far from meeting the demand. Therefore, `intelligent'' monitoring becomes more and more urgent. At present, the space-based independent video surveillance technology is a hot spot in the field of computer vision, which involves in image processing, pattern recognition and artificial intelligence. This research is rich in content and has a wide application range. The key independent recognition technologies of abnormal moving targets are summarized from three aspects. The key algorithms are presented. The advantages and disadvantages of some typical algorithms are analyzed. The technical route with excellent robustness, high real-time performance and good detection effectiveness is given.