Removal of Translation Bias when using Subspace Methods
نویسنده
چکیده
Given estimates of the motion eld (optic ow) from an image sequence, it is possible to recover translational direction, ~ T , using a variety of techniques. One such technique, known as \subspace methods," generates constraints which are perpendicular to ~ T , so that two distinct constraints allow a solution for ~ T . In practice many constraints are used in a least-squares solution, but it has been observed that the recovered estimates for ~ T are biased towards the optical axis. While the cause of the bias is well known, previous attempts to remove it have been awed. This paper outlines a new method which removes the bias. The technique is simple to apply and computationally e cient.
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