Abstract:Aimed at strict mosaic of unmanned aerial vehicle (UAV) images with few control information, this paper introduces the principles of the free network bundle adjustment, calculation process and an error model is deduced. Four adjacent images in the west of Zengcheng, Guangdong province are chosen from two flight strips for a test. With the method, the accuracy inconsistency problem of control information in Google Earth is solved. By selecting the weights, strict mosaic of UAV images with coordinate and projection information are implemented. An analysis of the relationship between angular, linear elements and mosaic errors provides theoretical basis for images mosaic with non control points or only relative control conditions.