HONG KONG BAPTIST UNIVERSITY
FACULTY OF SCIENCE

Department of Computer Science Seminar
2011 Series

Representing Character Motion by Spatial Relationships

Mr. Edmond Shu-lim Ho
University of Edinburgh

Date: February 14, 2011 (Monday)
Time: 3:30 - 4:30 pm
Venue: SCT716, Cha Chi Ming Science Tower, Ho Sin Hang Campus

Abstract
Close interactions, not necessarily with any contacts, between different body parts of single or multiple characters or with the environment are common in computer animation and 3D computer games. Yoga, wrestling, dancing and moving through a constrained environment are some examples. Existing scene representations have a fundamental limitation in handling such close interactions. Currently, a motion is typically described in terms of joint angles and kinematic constraints such as contacts. With this representation, automatically computing a valid motion requires randomized exploration and significant computation for collision detection. The animator also needs to shoulder the burden of specifying all the kinematic constraints in advance. From the animator's perspective, this is impractical and not conductive to manual editing. Competitive automatic solutions require an effective representation that allows the extraction of spatial relationships from existing motion data and synthesis of new animations that preserve these relationships. Such a representation will not only allow quantitative evaluation of the way different body parts are interacting, but also facilitate qualitative characterization of scene semantics.

I have been exploring new representations that consider the spatial relationships for describing the interactions of multiple characters or characters in a constraint environment. In this talk, I introduce two of the proposed methods. The first representation is called the topology coordinates that describes body parts twisted around each other. The second representation is called the interaction mesh, which describes which body parts are in close proximity to others. Using these representations, we can easily edit or retarget human motions while preserving the context of the scene. The methodologies have a wide range of applications in fields of computer animation, pattern recognition and robotics. I will first briefly cover the overview of each method, and then show some demonstrations of applying them to character motion synthesis.

Biography
Edmond Shu-lim Ho received the BSc degree in Computer Science from the Hong Kong Baptist University in 2003 and the MPhil degree from the City University of Hong Kong in 2006. He is currently working toward the PhD degree in the School of Informatics, University of Edinburgh. His research interests include physically based animation, and human motions analysis and synthesis.

********* ALL INTERESTED ARE WELCOME ***********
(For enquiry, please contact Computer Science Department at 3411 2385)

http://www.comp.hkbu.edu.hk/v1/?page=seminars&id=167&lang=sc
Photos  Slides 1  Slides 2