Estimation for CAD Model

We describe a system for semiautomatically extracting 3-D object models from raw, uncali-brated video. The system utilizes a recursive estimator to accurately recover camera motion, pointwise structure, and camera focal length. Recovered 3-D points are used to compute a piecewise-smooth surface model for the object. Recovered motion and camera geometry are then used along with the original video to texture map the surfaces. We describe extensions to our previously-reported geometry estimation formulation 2] that incorporate focal length estimation and other improvements, so that accurate estimates of structure and camera motion can be recovered from uncalibrated video cameras. We also discuss the buildup of texture maps from sequences of images, which is important in producing realistic-looking models. Since the computations parallel those used in computer graphics, eecient hardware already exists for doing this part of the mod-eling. Examples demonstrate generation of a realistic 3-D texture-mapped model from a video sequence, the post-production manipulation of video, and the combination of computer graphics models with video.