Since a plurality of image data are stored in a single file, high-speed access
to image data and easy management of image data are allowed, and information that
pertains to each image data can be acquired from a source outside the image file.
As an arrangement for this purpose, an image data area (202) continuously
stores a plurality of compressed image data. An index area (204) stores
reference information to a source outside the file, which pertains to each of the
plurality of image data stored in the image data area (202), in the order
the plurality of image data are stored. A feature amount data area (203)
stores feature amount data obtained from the images stored in the image data area
(202). Furthermore, an image information area (201) stores header
information including information indicating the start position of each area.
