某型航侦CCD相机图像重叠率波动分析

Fluctuation Analysis of One Aerial Reconnaissance CCD Camera Image Overlap Rate

根据某型航侦CCD相机的工作原理,选择合适的笛卡尔坐标系,并用坐标变换描述两幅图像在不同时刻和扫描倾角下的关系。利用成像共线原理,推导出扰动下的图像仿射变换模型。仿真分析表明,图像在航向和航侧上的重叠率波动幅度分别由俯仰角和滚动角扰动量决定,通过补偿两个姿态的扰动量可以将图像重叠率波动范围缩小在一定的范围内,满足图像拼接的要求。最终的飞行测试效果也验证了这一点。这不仅可以为同类相机的重叠率及其补偿装置设计提供理论依据,也可以简化后续图像拼接处理的配准过程。

According to the work principle of one aerial reconnaissance CCD camera,Descartes coordinate systems are properly build.Transformation of the coordinates is used to describe the relationship with two images which were taken in different times and scanning angles.Image affine transformation model with disturbance is derived by co-line principle.Then,a simulation analysis is given.Results of simulation indicate that volatility of image overlap rate in the direction of heading and side is determined by pitching and roll angle disturbance separately,and it can be reduced into a certain range by compensating the two attitude disturbance.Finally,it＇ll meet the demand of image mosaicing.Flying test result has proved this conclusion effectively.It can supply a theory basis for the overlap rate and compensation mechanism design of the same species camera,and it also can simplify the registration process of the image mosaicing.