The images classified by photographic baseline are as follows

The connection between two photography stations of a stereo image pair. (1) During aerial photography, the aerial camera continuously exposes the connecting line of the spatial positions of the front nodes of the two objective lenses. This spatial baseline value is always unknown and can only be obtained by applying ground control points to reverse the direction elements of the photo. (2) In the ground stereo photogrammetry, the photographic baseline can be accurately determined by the measurement method, so its value is always known. However, the spatial position of the camera can also be obtained from the control point. [ 1]