PURPOSE: To exactly and easily encode a font letter style by dividing the contour of a character into horizontal sections having the boundary corresponding to a horizontal line across a vertical preceding point, and dividing the correspondent conical curve fragments of vertically adjacent subsections to keep the continuity of inclination at their intersections.

CONSTITUTION: The boundary is adopted so as to divide the character into the partial horizontal sections of maximum and minimum values in the longitudinal direction of character contour form. Sections 1, 3, 5, 7 and 9 respectively include only one member and the remaining sections respectively include two members on the other hand. A section member 2b is further decomposed into curved trapezoidal subsections 12. The best number of subsections is determined by a curved trapezoid generation computer program according to the complexty of character contour form corresponding to the section members, and the continuity of inclination at the point connecting the adjacent curved trapezoidal subsections is maintained. Thus, when the character is reproduced, unwanted wavy appearance is prevented.