Fast and Robust Motion Tracking for Time-Varying Mesh Featuring Reeb-Graph-Based Skeleton Fitting and its Application to Motion Retrieval

In this paper, an algorithm for motion extraction from time-varying mesh (TVM) is proposed. TVM is a sequence of 3D models made for real-world dynamic objects. In TVM, detailed information of 3D objects such as shape, color, and motion is stored. Therefore, TVM is an attractive technology for the next-generation multimedia. However, the management of TVM database for archiving and retrieving is a significant problem because it is difficult to locate and track feature points in TVM. For efficient and effective archive and retrieval systems, motion extraction and tracking is essential. In our approach, skeletons are extracted from TVM using Reeb graph, and motion tracking is achieved by fitting a reference skeleton to the others. We defined a geodesic function using principal component analysis (PCA) for fast and noiseless skeleton extraction. Robust fitting has been realized by an end node tracking strategy. In addition, we have developed an efficient motion retrieval system compatible to conventional motion capture (mocap) data using the extracted skeleton. As a result, low-cost query generation using mocap systems and cross search between TVM and mocap data have been achieved.