Docking aircraft extraction from the captured image sequence and its shadow detection are the key works in the Visual Docking Guidance System. The algorithm based on Mixture of Gaussians (MOGS) is widely used to subtract static background. However

the real time performance of the MOGS algorithm is reduced remarkably when high resolution image is processed

the “bad tail” phenomenon occurs when slowly moving and large object is extracted

and the shadow of moving object can not be detected. An improved MOGS algorithm based on hierarchical image is proposed

and the problems of bad real time and “bad tail” phenomenon are solved. On this condition

a new shadow detection algorithm based on color character and region character is presented

partially spatial constraints are used

and the shadow of moving object is detected exactly. The experimental results in Visual Docking Guidance System show the validity and the practicality of the algorithms.