In a system for displaying, in a text to which only one font can be designated, a character that cannot be output in the font designated in the text in an alternative font, the whole text is changed to the alternative font, so that a rendering result on the display side and a rendering result on the output side differ from each other. The text rendered during the display is acquired, and is divided into texts for each font if it is displayed in an alternative font, and output data are respectively generated as the individual texts.