| 摘要 |
PURPOSE:To easily know when there is an error in a display of a position of a vehicle and estimate a true position of the vehicle. CONSTITUTION:A map-matching part 12 reads out map data of the periphery of a position of a vehicle from a CD-ROM 1 to a buffer memory 11 based on the position of the vehicle detected by a GPS receiver 2, and carries out map-matching based on the read-out map data. The position of the vehicle is corrected on a road. A map image-drawing part 13 draws to a video RAM 15 a map image including the corrected position of the vehicle with the use of the read-out map data in the buffer memory 11, and moreover, the drawing part 13 draws a post-correction mark at a point corresponding to the corrected position of the vehicle on the drawn map image and a pre-correction mark at a point corresponding to the position of the vehicle before corrected in a distinguishable manner. The image of the video RAM 15 is read out by an image-converting part 16 and converted to a predetermined video signal which is then output to a display device 4 to be displayed on a screen. |
