| 摘要 |
PURPOSE:To emphasize a second picture image superposed on a first picture image to distinctly confirm the drawing position of a vector image by removing image elements of the first picture image at intervals of a prescribed number of elements to make the picture image apparently thin. CONSTITUTION:When image data of a road map is stored in an image storage device 21 and vector data based on the present position corresponding to the map data storage position in the image storage device and the going direction is stored in a vector storage device 24, image data stored in the image storage device 21 has image dots removed at intervals of a prescribed number of dots by a thinning device 22 and is written in a frame memory 26 by an image drawing device 23. Image data is printed or displayed with the image dot density which is preliminarily reduced in accordance with the thinning processing, and simultaneous print or vector data is emphasized. Thus, the drawing position of the vector image is distinctly confirmed. |
