"n of a position computation section. [0019]FIG. 4 is a conceptual view showing the relationship between camera coordinate systems. [0020]FIG. 5 is a conceptual view demonstrating image synthesis using the plane of road surface as the reference. [0021]FIGS. 6A and 6B are examples of a first synthesized image produced by an image variable-synthesis section in Embodiment 1. [0022]FIG. 7 is an example" . . . .