In the present invention, image data is edited in response to a demand transmitted from a data-processing apparatus through a network. A moving-picture server (3) acquires a scenario consisting of a plurality of scenes, each lasting for a given time, is acquired in response to a demand made by a personal computer (1-1). The server acquires from a temporary edition space (6) a given number of original data items that will be used in the scenario, also in response to a demand made by the data-processing apparatus. The moving-picture server (3) selects prescribed ones of the original data items acquired and allocate them to the scenes of the scenario acquired. The server corrects the original data items selected, in accordance with the prescribed image data items that have been allocated to the scenes of the scenario. The image data is thereby edited.