为避免近景影像信息投影变换的立体摄影测量工作方式,本文探讨地面摄影的单像投影变换方法及其实际应用.研究表明,无需转换数字高程模型(DEM)的投影面,顾及近景影像和DEM的关系,将投影光线投影至不同坐标平面处理,地面摄影单像投影变换对各种目标形态的计算均能够正确收敛;基于普通数码影像的单像投影变换物方坐标的相对误差小于摄影纵距的1/600,能够满足对工程信息的大比例尺投影变换的精度要求.结合普通数码相机量测化技术,地面摄影单像投影变换能为基于影像的工程监测带来新的技术支持.
The paper studied the algorithm and application of digital projective generation from a single ground image for the sake of avoiding the stereo way of it. Researches proved that in engineering, without the conversion of DEM perspective plane, digital projective generation a single ground image could be correctly calculated to various target form when taking into account the relation between the digital terrain modal and it' s ground image, and by projecting the projective light onto different coordinate plane. The object space coordinates' relative error of the digital projective generation from a single ground image captured by a common digital camera is less than 1/600, and it can meet the accuracy needs of large-scale projective generation of engineering information. The experiment has satisfied the requirements of engineering geologic mapping of 1:100 scale. Consequently, when combined with the metrilizing technology of common digital camera, digital projective generation from a single ground image would bring a new technology support for engineering monitor based on imagery.