Dense 3-D Structure from Image Sequences Using Probabilistic Depth Carving

We describe an algorithm to determine dense 3-D structure in a static scene from an image sequence captured by a moving camera. Metric camera motions are first determined using a recursive structure from motion algorithm based on tracked feature points. Dense depth information for a subset of key frames is then obtained using a novel probabilistic depth carving algorithm - analogous to space carving - in which depth probabilities obtained locally about the key frames are combined in 3-D space. An important component in this process is that opacity and occlusion relationships are modelled explicitly, enabling consistent combination of the depth probabilities. Results of experiments on a real sequence illustrate the effectiveness of the approach.