According to one embodiment, an image processing device that processes a first image and a second image captured by a camera includes a first circuit, a second circuit and a third circuit. The first circuit determines a first position of a first reference line and a second position of a second reference line in at least one of the first image and the second image. The second circuit determines a image deformation reduction parameter based on a line width from a first reference point on the first reference line at the first position to a second reference point on the second reference line at the second position. The third circuit reduces image deformation in the first image or the second image based on the image deformation reduction parameter.