Rights Creative Commons: Attribution 3.0 Hong Kong License FAST ROTATION CENTER IDENTIFICATION METHODS FOR VIDEO SEQUENCES

Rotational motion can often be seen in video. How-ever, comparatively little research has been done to inves-tigate rotational motions in video, whose analysis could be useful. For example, if we can efficiently identify the ro-tation center of a spinning object, extraction and tracking of it can be made easier by grouping points moving at the same radial speed. It could also improve compression by synthesizing analyzed spin transitions, and help tracking of rotating objects. In this paper, we introduce a set of ro-tation center location methods using only the motion field constructed during video encoding, along with a few meth-ods for improving their performances. These methods can be implemented using integer operations only. They are up to 1.81 times faster than the traditional circulation analysis method with little sacrifice in accuracy, and are not affected by asymmetric fields caused by translational motions. 1