一种内部参数可变的摄像机自定标新方法

在计算机视觉的研究中 ,定标、运动、结构与匹配是常用到的 4个方面的信息 ,而定标是进行运动和结构分析的必要条件 ,不需要参照物而利用图像系列进行摄像机自定标问题在 2 0世纪 90年代初就有所突破。然而 ,大多数自定标研究仍然集中于在视觉任务完成过程中摄像机内部参数固定不变的情况 ,在内部参数发生变化时 ,这些方法还不能适用。扩展以前利用Kruppa方程进行摄像机自定标的方法 ,通过对基础矩阵进行奇异值分解(SVD) ,将Kruppa方程简化 ,得出了一种可处理内部参数发生变化时的摄像机自定标方法。仿真实验证明了该方法的可行性。     

A novel method of systematic error compensation for a position and orientation system

A novel method is introduced for self-calibration and elimination of systematic errors for a position and orientation system （POS）. The method uses a combined bundle block adjustment with POS data （named the POS-supported bundle block adjustment） without a calibration field. On the basis of delivering strict observation equations for POS data, the specific scheme of compensating the translation and drift systematic errors in a POS is given, and a prototype system WuCAPS is developed. The effects of eliminating POS systematic errors using the POS-supported bundle block adjustment for different ground control conditions are tested using two sets of actual aerial photos. The first set was taken over a fiat region in the suburbs of the city of Yingkou in China and tested at a scale of 1：2500. The second set was taken over a high mountainous region in the desert region of Xinjiang in China and tested at a scale of 1：32,000. The empirical results verified that the POS systematic errors can be completely eliminated and the photo elements of exterior orientation obtained by the POS-supported bundle block adjustment can satisfy the requirements of aerial photogrammetric topographic mapping when four full ground control points （GCPs） are emplaced in the comers of the adjustment block for large-scale images of flat regions, but only one full GCP emplaced in the center of the adjustment block is needed for medium-small scale images of mountainous regions. This not only demonstrates the validity of the established mathematical model and the feasibility of the method proposed in this paper, but also avoids the use of a special calibration field. Therefore, it can simplify the existing POS operation rules and dramatically save on practical application costs, laying the theoretical foundation for widesoread use of POS.