Joint estimation of shape and motion from silhouettes

This paper presents a fast algorithm for recovering shape and motion of dynamic scenes from sequences of silhouettes in calibrated multi-camera settings in wide-baseline configurations. The proposed method captures the static shape on the first frame by deforming an arbitrary set of points located on an initial surface enclosing the actual scene. Then, the initial 3D shape is propagated in subsequent frames by quickly deforming the initial static shape in order to fit the available silhouettes. The resulting points lie on the surface of the Visual Hull. Shape and motion descriptions are jointly obtained by the dynamic procedure that adapts existing surfaces to the set of silhouettes at each new time instant. Experimental results show how the proposed dynamic method obtains silhouette-consistent shape estimates -with the same accuracy than a static approach- and dense motion estimates with very low usage of computational resources, by exploiting both spatial and temporal redundancies.