An empirical comparison of methods for image-based motion estimation

This paper presents a comparison between methods that estimate motion of a camera from a sequence of video images. We implemented two methods: a homography based method that assumes planar environments; and shape-from-motion, a general method that can deal with a fully three dimensional world. Both methods were formulated in an iterative, online form to produce estimates of camera motion. We discuss a trade-off in accuracy and run time efficiency based on experimental results for these two general methods in relation to ground truth. We show how a variation of the homography method can produce accurate results in some cases when the environment is non-planar with low computational cost.