To provide a technology of properly specifying a process target frame in a dynamic image in accordance with a user's instruction. A frame specifying device plays a dynamic image, receives, when a user performs an operation of instructing execution of a process about a partial scene in the dynamic image, an instruction signal based on the user's operation, and specifies, as triggered by receiving the instruction signal, a frame under the play or a frame distanced by a predetermined length of time from the frame under the play as the process target frame when receiving the instruction signal in the frames constructing the dynamic image.