A method for tracking the pose of known 3-D objects based on an active contour model

A method for tracking the pose of known 3-D objects moving with 6 degrees of freedom in space is described. The main idea is to split the tracking into two quasi autonomous working processes, one to track the 2-D outline (i.e. silhouette) of the object in an image sequence and one to track the full 3-D object pose based on the estimated 2-D outline. An active contour model utilizing a Kalman filter is used to efficiently track the object outline. Geometric information used is limited to the space curve at the object´s surface projecting to the currently visible outline. The 3-D pose tracker uses the results of the contour tracker, i.e. the position and shape of the outline, and a 3-D object model to track the full object pose. The object pose is derived from an n-point correspondence between the outline and the object´s surface. Furthermore, the pose tracker predicts the object appearance and provides the contour tracker with new model information in case the object aspect changes. Tracking results for polyhedral objects are presented