Image display device, image display method, image display system, image data transmitting device, program, and storage medium

A control section of a slideshow display device includes a display control section. The display control section causes a list of thumbnails to be displayed when a display timing at which a target image other than a currently displayed image is to be displayed comes before a predetermined point in time. As such, when display delay occurs, a list of thumbnails can be displayed, instead of the target image. This realizes an image display device which prevents a user from being subject to stress when display delay occurs in slideshow display.