twist+1
Hierarchical spring systems
Spring systems describe spatial relationships between features of object parts in a tolerant and deformable way. Instead of tracking multiple features (e.g. interest points) of object parts independently, our representation integrates the underlying structure into the tracking process. The spring system is represented by an attributed graph (attributes are features of object parts and represented by vertices). During tracking the spring system produces offset vectors for each feature to correct the estimated positions of the tracking algorithm. With the help of spring systems one is able to successfully associate the features of objects in ambiguous cases (e.g. features of background are similar to target object, occlusions …). We extended our first concepts of this representation [26] (see publications) to articulated objects consisting of multiple object parts [40,43] (see publications) and then to a hierarchical spring system (attributed graph pyramid), where the information is transferred over articulation points from one spring system to the other [41] (see publications). The resulting representation describes objects of arbitrary complexity (e.g. rigid object, articulated objects consisting of several parts and joints). Video 1 to 5 show results.
Video 1: Tracking selected checkerboard fields without spring system.
Video 2: Tracking seleted checkerboard fields with spring system.
Video 3: Tracking selected color regions on scissors without spring system (structure).
Video 4: Tracking selected color regions on scissors with spring system (structure).
Video 5: Tracking rigid parts of articulated object, each with a hierarchical spring system connected via articulation points.
Last modified: May 07, 2010 by Nicole M. Artner