Department of Computer Science & Information Engineering, National Cheng Kung University, No. 1, University Road, Tainan City 701, Taiwan.
IEEE Trans Vis Comput Graph. 2012 May;18(5):729-40. doi: 10.1109/TVCG.2011.53.
The rapid growth of motion capture data increases the importance of motion retrieval. The majority of the existing motion retrieval approaches are based on a labor-intensive step in which the user browses and selects a desired query motion clip from the large motion clip database. In this work, a novel sketching interface for defining the query is presented. This simple approach allows users to define the required motion by sketching several motion strokes over a drawn character, which requires less effort and extends the users’ expressiveness. To support the real-time interface, a specialized encoding of the motions and the hand-drawn query is required. Here, we introduce a novel hierarchical encoding scheme based on a set of orthonormal spherical harmonic (SH) basis functions, which provides a compact representation, and avoids the CPU/processing intensive stage of temporal alignment used by previous solutions. Experimental results show that the proposed approach can well retrieve the motions, and is capable of retrieve logically and numerically similar motions, which is superior to previous approaches. The user study shows that the proposed system can be a useful tool to input motion query if the users are familiar with it. Finally, an application of generating a 3D animation from a hand-drawn comics strip is demonstrated.
运动捕捉数据的快速增长增加了运动检索的重要性。现有的大多数运动检索方法都基于一个劳动密集型的步骤，即用户从大型运动片段数据库中浏览和选择所需的查询运动片段。在这项工作中，提出了一种用于定义查询的新颖的绘图界面。这种简单的方法允许用户通过在绘制的角色上绘制几个运动笔画来定义所需的运动，这需要更少的努力并扩展了用户的表现力。为了支持实时界面，需要对运动和手绘查询进行专门的编码。在这里，我们引入了一种新的基于一组正交球谐（SH）基函数的分层编码方案，该方案提供了紧凑的表示形式，并避免了之前解决方案中使用的 CPU/处理密集的时间对齐阶段。实验结果表明，所提出的方法可以很好地检索运动，并且能够检索逻辑和数值上相似的运动，优于以前的方法。用户研究表明，如果用户熟悉它，那么该系统可以成为输入运动查询的有用工具。最后，演示了从手绘漫画生成 3D 动画的应用。
