The application provides a three-dimensional model construction method and
system for topographic survey, and belongs to the technical field of model construction. The method comprises the following steps: segmenting
satellite images of a target survey area based on the complexity of the
terrain to obtain complex
terrain areas and open
terrain areas; obtaining
laser scanning data of the complex terrain areas and low-altitude image data of the open terrain areas; fusing the
laser scanning data and the low-altitude image data to obtain a target
data set corresponding to the target survey area; constructing a
regular grid model corresponding to the target survey area based on the target
data set; constructing an irregular
triangular grid model corresponding to the target survey area based on the
laser scanning data; and fusing the
regular grid model and the irregular
triangular grid model to obtain a three-dimensional model of the target survey area. The three-dimensional model construction method and
system for topographic survey can improve the modeling accuracy.