Towards automatic aerial triangulation

Digital photogrammetry has a great influence on aerial triangulation. Several digital aerial triangulation systems are now in various stages of development. Two distinct different approaches can he observed: interactive systems which require human operator guidance and softcopy workstations; and automatic systems. Automatic aerial triangulation systems attempt to reduce the aerial triangulation problem to a batch process, with little or no help of a human operator. Today's systems are close to meet this challenge, but the identification and measurement of control points remains an interactive task. The paper focuses on automatic aerial triangulation. Major effort is spent on identifying essential tasks that are independent of existing systems. The tasks, such as selecting suitable tie points, determining accurate approximations and matching multiple images, are derived from the objectives of digital aerial triangulation and by considering the potential of image processing and computer vision. The solution of these essential tasks brings a myriad of challenging problems. The concluding remarks comment on the differences between traditional and digital approaches and discuss the consequences.