期刊名称：ISPRS Annals of the Photogrammetry, Remote Sensing and Spatial Information Sciences
印刷版ISSN：2194-9042
电子版ISSN：2194-9050
出版年度：2003
卷号：XXXIV-3/W8
出版社：Copernicus Publications
摘要：A non-metric digital camera is required to be geometrically calibrated when it is used for photogrammetric applications. Many camera calibration methods for a non-metric digital camera have been proposed. However there is no standard procedure to evaluate an estimated image distortion model directly. Calibration results are usually evaluated indirectly by such indexes as residuals on image, three-dimensional measurement errors of control points, and error estimates of obtained camera parameters. Therefore, we conducted a numerical simulation in order to examine capabilities of these indexes. In the simulation nine images were supposed to be acquired vertically to shoot 1024 control points on four layers disposed at regular intervals of the depth. Seven sets of 1024 control points were prepared, and these sets varied in the depth of the distribution of control points from 2/3 to 1/96 of the average camera height. In the simulation 49 cases with different sets of control points and different precision of image coordinates were investigated. Numerical simulation results show the limits of capabilities of these indexes. A larger value of one of these indexes obtained in a camera calibration usually means that the image distortion model estimated by the calibration is not reasonable. On the other hand, smaller values of all of these indexes do not always mean that the estimated image distortion model is appropriate. Thus the authors propose that a set of the prior and posterior numerical simulations should be conducted in a camera calibration to evaluate calibration results in addition to conventional evaluation by using the abovementioned indexes
