A moving object comprising: an imaging device placed in an installation height, H, from a road surface and which captures an image of the road surface; an image processing unit which calculates a movement amount of the moving object based on images captured by the imaging device; and the image processing unit is configured to: extract a plurality of first feature points from a first image captured at a first timing, extract a plurality of second feature points from a second image captured at a second timing after the first timing, perform tracking on each of the plurality of first feature points to each of the plurality of second feature points, calculate a movement amount and a relative speed, v mn, of each of the plurality of second feature points, wherein the movement amount is a difference, Δd mn, between a relative Position, d (m-1)n, of a feature point extracted in a previous frame and a relative position, d mn, of the feature point extracted in a current frame, and calculate a movement amount, ΔD m, of the moving object based on the movement amounts of the plurality of second feature points; the image processing unit being characterized in that it is configured to: calculate a movement amount, Δ Dm, of the moving object based on the movement amounts of feature points having a relative speed, v mn, within a predetermined range among the plurality of second feature points, wherein the predetermined range depends at least on a threshold, V threshold, which varies based on a time series information of the speed, V m-1; V m-2; V m-3, of the moving object calculated in the past, and wherein the speed, V m, of the moving object is calculated based on the movement amount and a time when an image is acquired by the imaging device. an imaging device placed in an installation height, H, from a road surface and which captures an image of the road surface; an image processing unit which calculates a movement amount of the moving object based on images captured by the imaging device; and the image processing unit is configured to: extract a plurality of first feature points from a first image captured at a first timing, extract a plurality of second feature points from a second image captured at a second timing after the first timing, perform tracking on each of the plurality of first feature points to each of the plurality of second feature points, calculate a movement amount and a relative speed, v mn, of each of the plurality of second feature points, wherein the movement amount is a difference, Δd mn, between a relative Position, d (m-1)n, of a feature point extracted in a previous frame and a relative position, d mn, of the feature point extracted in a current frame, and calculate a movement amount, ΔD m, of the moving object based on the movement amounts of the plurality of second feature points; extract a plurality of first feature points from a first image captured at a first timing, extract a plurality of second feature points from a second image captured at a second timing after the first timing, perform tracking on each of the plurality of first feature points to each of the plurality of second feature points, calculate a movement amount and a relative speed, v mn, of each of the plurality of second feature points, wherein the movement amount is a difference, Δd mn, between a relative Position, d (m-1)n, of a feature point extracted in a previous frame and a relative position, d mn, of the feature point extracted in a current frame, and calculate a movement amount, ΔD m, of the moving object based on the movement amounts of the plurality of second feature points; the image processing unit being characterized in that it is configured to: calculate a movement amount, Δ Dm, of the moving object based on the movement amounts of feature points having a relative speed, v mn, within a predetermined range among the plurality of second feature points, wherein the predetermined range depends at least on a threshold, V threshold, which varies based on a time series information of the speed, V m-1; V m-2; V m-3, of the moving object calculated in the past, and wherein the speed, V m, of the moving object is calculated based on the movement amount and a time when an image is acquired by the imaging device.