Active surface reconstruction by integrating focus, vergence, stereo, and camera calibration

A method is described for estimating surfaces from stereo images. A single pair of stereo images can yield surface reconstruction for only a small volume of space. Since the scene may be large, images are obtained dynamically using different camera configurations through the control of focus and camera vergence. For smooth objects, this results in the reconstruction of surface patches that are contiguous and overlapping. These sequentially acquired surface maps are merged into a central, composite representation. During camera reconfiguration, unpredictable calibration errors may arise. Therefore, this method permits small changes in calibration parameter values to achieve agreement between adjacent reconstructed patches in the areas of overlap. To integrate the different sources of depth information, and to balance the effects they have on the resulting surface estimate, the surface reconstruction problem is formulated as one of optimization.