1. An image processing apparatus comprising: an obtaining unit adapted to obtain a plurality of reduction images from a storage medium storing storage images, each of the reduction images corresponding to a respective one of the storage images; a first display control unit adapted to cause a display device to display the plurality of reduction images obtained by said obtaining unit; a reduction image selection unit adapted to select reduction images from among the plurality of reduction images displayed by said first display control unit; a second display control unit adapted to effect, in a size larger than that of the reduction images, automatic sequential display of images corresponding to the stored images which correspond respectively to the reduction images selected by said reduction image selection unit; a designating unit adapted to designate a plurality of images among the images displayed by said second display control unit in the size larger than that of the reduction images, as an image to be subjected later to a specific image process; a storing unit adapted to continue, at least up to completion of the automatic and sequential display with the larger size by said second display control unit, to store information indicating the plurality of images designated by said designating unit as the images to be subjected later to the specific image process; and a specifying unit adapted to specify the storage images corresponding to the plurality of images indicated by the information stored by said storing unit as an image group to be subjected to the specific image process, when the automatic sequential display by said second display control unit is completed.