IMPLICIT RECONSTRUCTION BY ZOOMING

This paper presents a new method for inferring 3D information using a static camera equipped with a zoom lens. The modeling algorithm does n ot require any explicit calibration model and the calculations involve d are straightforward. This approach uses several images of accurate r egular grids placed on a micrometric table, as the calibration process . The basic idea is to compute a local transformation that allows the establishment of a relationship between a distorted grid detected on t he CCD matrix and the real one located in front of the camera. This re lationship takes automatically into account all distortion phenomena a nd allows one to obtain reconstruction results much more accurate than those of previous works in the same field. A complete experiment on r eal data is provided and shows that it is possible to compute 3D infor mation from a zooming image set even if data are close to the optical axis. (C) 1997 Academic Press.