1. An image processing apparatus comprising: an input unit configured to input plural page images; an extraction unit configured to extract a foreground image from each of the plural page images input by said input unit; a page data generation unit configured to generate page data which includes the foreground image extracted by said extraction unit; an announcement page data generation unit configured to generate announcement page data corresponding to a page image from which the foreground image has not been extracted by said extraction unit, the announcement page data having a link to a reference image including a background image of a page image from which the foreground image has not been extracted by said extraction unit; and a file generation unit configured to generate a file which includes the page data generated by said page data generation unit and the announcement page data generated by said announcement page data generation unit, wherein said input unit, said extraction unit, said page data generation unit, said announcement page data generation unit and said file generation unit are implemented at least in part by at least one processor and at least one memory.