An operation device includes a rotational operation element, an angular velocity detection portion detecting an angular velocity of a rotational operation on the rotational operation element, and a playback speed information computation portion calculating, when the angular velocity detected by the angular velocity detection portion is in a first velocity range including an angular velocity of 0, playback speed information according to the detected angular velocity through a first functional computation and when the angular velocity detected by the angular velocity detection portion is in a second velocity range, which is a range higher than the first velocity range, playback speed information according to the detected angular velocity through a second functional computation, and outputting the calculated playback speed information.