October 17, 2006

1
Motion Segmentation and RetrievalJackie Assa,
Y. Caspi and Daniel Cohen-OrAction Synopsis
Pose Selection and IllustrationACM Transaction
on Graphics(SIGGRAPH 2005) 24(3), 667-676

• October 17, 2006
• Sung Yong Shin
• Computer Science Dept.

2

• Action Synopsis Pose Selection and
  Illustration

short motion
joint configuration (at a frame)
motion curve dimension reduction a sequence of
extreme points
composing the selected poses into a small number
of images
Summary (or abstraction) How? pose selection
and illustration, i.e., choosing a sequence
of key poses and properly drawing them
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• Why Action Synopsis?
• short sports events (news papers)
• dynamic experiments (scientific journals)
• thumbnails of video clips or animations (digital
  libraries)

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• Pose Selection
• motion aspect extraction
• to define inter-pose distance
• joint positions and angles linear and angular
  velocities
• dimensionality reduction
• RMDS (Replicated Multi-Dimensional Scaling)
• embedding a motion curve into a low-dimensional
  space while preserving inter-pose dissimilarity
• choosing poses
• local extreme points
• temporally far apart

5

• Pose Illustration
• scene background (reflecting action context)
• image layout
• self-occlusion

6

• Conclusions
• non-skeletal representations of motions
• more sophisticated selection rules
• multiple characters