CAD (Computer Aided Design) data and orthoimage matching and overlapping method

The invention discloses a CAD (Computer Aided Design) data and orthoimage matching and superposing method, which comprises the following steps of: acquiring image file height and width information of an orthoimage through a PIL (Precision Image Library) library by using a Python programming language, and acquiring the resolution ratio and the left upper corner pixel coordinate of the orthoimage file in the X/Y direction from a coordinate file; according to the method, the image file of the orthoimage is obtained through a program, then parameters required for inserting the orthoimage into the CAD are calculated through a formula in Python, and the parameters comprise insertion point coordinates and scaling, so that CAD data and the orthoimage are matched and superposed, the attributes of the image file of the orthoimage are obtained through the program, and the parameters required for inserting the image file into the CAD are automatically calculated. The data are matched and superposed with corresponding vec