To estimate a road model having relatively high reliability.
A CCD camera 1 is mounted on one's own vehicle; the front scene of the vehicle is imaged by the CCD camera 1; and the obtained image is introduced into an ECU 3 comprising a microcomputer through a video capture board 2, and processed by the ECU 3. Density value of all the pixels of the image introduced by the ECU 3 are subjected to a differential process to form an edge image; a plurality of lane marker candidate points corresponding to lane markers (white lines) formed on the road are extracted from the formed edge image; the coordinates of a plurality of the extracted lane marker candidate points are found; and an H∞ filter is applied to them to derive a road parameter for defining the road model.
YAMADA KENICHI
ITO TOSHIO
Kakusho Shoichi