PURPOSE: To reduce the amount of data to be stored by storing contours of an image of a figure or character as a set of pieces of information and dividing and storing the contours of the image.

CONSTITUTION: Figures show a symbol '+', divisions of the '+', and respective coordinate points 401 - 412, 501- 504, and 601 - 604. Then information on the contours of the image is stored as a set of pieces of information on dots and the image is divided according to the stored set of the pieces of information on the dots and stores. The contour can be divided only when the intersection part of the image is linear and can be divided into ≥2 contours. Consequently, coordinate data on the intersection part are not necessary and the amount of the stored data can be reduced.