A study on 3D model construction of Morioka Castle stone walls using photogrammetry to estimate camera parameters for old photograph of Morioka Castle

Morioka City is planning to restore the ruins of Morioka Castle in order to preserve its historical values. However, the only existing photograph is an old photograph of Morioka Castle. To calculate the actual size of the object from the photograph, information on the relative positions of the camera and the object, as well as the camera's focal length, is required. Those estimations require an object whose actual size is known and the center of the photograph. However, the center of the image is unknown because this photograph is trimmed by the original photograph. To construct a virtual space for simulation, a 3D model with actual size is required. Therefore, this paper describes the method to create 3D model with actual size in virtual space.