thumbnail furthermore as described later with reference to fig4 as a display form of a pair of thumbnails a form is adopted in which a plurality of thumbnails here two thumbnails belonging to the pair are spatially arranged in a vertical or horizontal direction so as to be displayed on an overall screen therefore in order to allow for such a display the thumbnail generation unit 44 changes the aspect ratio of the replay target moving image to generate some sets of data of thumbnails with lower resolution in other words the thumbnail generation unit 44 generates data of each thumbnail in a manner such that a plurality here two of thumbnails can be displayed while maintaining a predetermined spatial or temporal positional relationship on a single screen of the display of the output unit 18 here the spatial positional relationship refers to a positional relationship in which two images are arranged spatially the spatial positional relationship includes for example a relationship in which the two images are arranged vertically horizontally or diagonally a relationship in which the two images are arranged so as to be spaced apart with a predetermined interval or a relationship in which the two images are arranged to be superimposed furthermore the temporal positional relationship refers to a positional relationship in which two images are arranged alongside on a temporal axis upon replay the temporal positional relationship includes for example a relationship of a replay time of two images that are replayed sequentially temporally to sum up the thumbnail generation unit 44 generates data of pairs of the thumbnails corresponding to pairs of the replay target moving images selected by the image selection unit 43 by the number equal to patterns of replay form of the pairs of replay.