Viewpoint estimation in three-dimensional images taken with perspective range sensors

We present a method for estimating the viewpoint from which a 3D image has been taken using a central-projection range sensor. We assume we have the 3 D coordinates of the points, organized with a known topology, but considera ble noise is present in the data. At points in the scene where there are su rface discontinuities, we estimate step rays through a linear interpolation . The viewpoint is found as the point of minimum distance to the set of ste p rays. To cope with noise, we define an unbiased distance measure. The min imization of the sum of distances provides the viewpoint. We present result s of several experiments carried out with 3D images of an old church.