Hao-Kai Wen's Website


RASP: A Comprehensive System for Complicated Actions in Halfpipe Sports


An action sequence panorama (ASP) extracts moving objects from different temporal steps, then stitches and aligns them onto a single panorama. Graceful actions performed by an athlete can be used to make an action sequence panorama (ASP). And, it is considered as an artistic presentation used to appreciate or to entertain. Whereas, ASP is hard to be applied to some sports in which moving objects in the panorama are overlapped together; therefore, ASP is seldom to be used to understand actions in sports.

We chose inline (inline-skate) vert (halfpipe) as the target sport of our case study to see if ASP can assist users to understand complicated sports actions.

In order to overcome "object-overlapping" issue, in this paper, ASPs recomposition method (RASP) is proposed and analyzed. It is designed based on the way that athletes developing their tricks:

  1. Almost every trick has a slight variation in making a different curve on the halfpipe.
  2. Most of the tricks can be performed at a higher position.

In this way, we get extra space to place objects in different temporal instants into different and non-overlap positions. The usage of RASP is natural and even be unaware to users. Besides, the halfpipe model and the action figure we used in user study can also be seen as an assisting learning tool for users, they provide an effective way for both professionals and amateurs to comprehend complicated actions in halfpipe sports.


Yi-Ling Ke, Hao-Kai Wen, Wei-Tai Chen, Hsiao-Ju Chang, Jia-Ling Wu.





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