1. An image processing device comprising: circuitry configured to: acquire a first image captured by a first imaging device in an optical head-mounted display (HMD), wherein the HMD presents a three-dimensional image, and wherein the first image captured by the first imaging device includes a part of an area including a field of view of a user wearing the HMD; acquire a second image captured by a second imaging device having an angle of view that at least partially overlaps an angle of view of the first imaging device; and detect a feature of the three-dimensional image based on the first image and the second image.