PURPOSE: To compress a data capacity and to shorten a processing time, by expressing line image data by the combination of the pseudo graphic character of the constituent of the line image data, and supplying the data by its character code.

CONSTITUTION: A line image is formed in a constituent unit by fractionizing it, and the pattern of the constituent of the line image is expressed in the pseudo graphic character, and also, correspondence by a specific character code is applied, and the patterns of those pseudo graphic characters are registered on the character pattern housing part 1a of a computer photo type setting machine 1, and the line image is formed as the set of the pseudo graphic characters. Thereby, it is possible to perform the correspondence by the code of the pseudo graphic character of the line image by dividing the image to the constituents, and to handle it at the same level as a character code. In such a way, it is possible to reduce the data capacity in the data of the line image compared with the image data of a bit pattern, etc., and to shorten a time required for the print processing of the line image.