1. An image editing device, comprising: image data acquisition section for acquiring a plurality of pieces of image data; page assignment section for determining, based on respective photographed times of the plurality of pieces of image data and a reference time interval, details of an assignment of the plurality of pieces of image data to each of a plurality of pages constituting a compilation so that an interval between photographed times of pieces of image data to be assigned to the each of the plurality of pages is the reference time interval or smaller; and page image output section for outputting image output data on the each of the plurality of pages based on the determined details of the assignment, wherein the page assignment section changes the reference time interval, to thereby determine the assignment that satisfies at least one of a condition for a maximum number of pieces of image data to be assigned to the each of the plurality of pages and a condition for a number of pages of the plurality of pages.