3. Feature Extraction of Motion Data
BVH rotation channels are used as features of motion for both the retrieval
instance and the motion data in this work. The BVH file format for motion
capture is originally developed by Biovision [20], a motion capture services
company, as a way to provide motion capture data to their customers. A BVH
file has two parts, a header section which describes the hierarchy and initial
pose of the skeleton; and a data section which contains the motion data [21].
In BVH format, all joints’ position can be calculated by their all parents’ local
rotation channels and root’s translation. The BVH format doesn't account for
scales so it isn't necessary to worry about including a scale factor calculation.