In order to form an image without losing a moving image included in a structured document, an MFP, when forming an image, receives print data and a moving image from a PC, stores the moving image in association with second moving image identification information, embeds, in a still image included in the print data, the second moving image identification information for the stored moving image and positional information included in the print data, and forms the still image on a sheet of paper. When reading an image, the MFP 100 reads a still image formed on a sheet of paper (S71), extracts second moving image identification information and positional information from the read still image (S73, S75), acquires a moving image identified by the extracted second moving image identification information (S74), and generates a structured document in which the moving image is associated with the still image in such a manner that the moving image is displayed at a position specified by the positional information in the still image (S89).