Shape representation and nonrigid motion tracking using deformable sup erquadrics

Dimitri Metaxas, Demetri Terzopoulos

Research output: Contribution to journalConference article

3 Scopus citations


This paper presents a physically-based approach to the recovery of shape and nonrigid 3D motion and the tracking of nonrigid objects. The approach makes use of deformable superquadrics (with additional parameterized tapering and bending deformations), dynamic models that offer global deformation parameters which capture large scale features and local deformation parameters which capture the details of complex shapes. We further present a generalization of the formulation to handle physically-based point-to-point constraints between models and to formally account for noise in the data using a recursive estimation technique based on Kalman filtering. Such constraints enable us to automatically assemble object models from interconnected deformable superquadric parts. The equations of motion governing the behavior of the models make them responsive to externally applied forces. These composite models can be used to track the motions of, articulated, flexible objects. We fit models to visual data by transforming the data into forces and simulating the equations of motion through time to adjust the translational, rotational, global and local deformational degrees of freedom of the models. We present model fitting and motion tracking experiments involving 2D and 3D data.

Original languageEnglish (US)
Pages (from-to)12-20
Number of pages9
JournalProceedings of SPIE - The International Society for Optical Engineering
Publication statusPublished - Sep 1 1991
Externally publishedYes
EventGeometric Methods in Computer Vision 1991 - San Diego, United States
Duration: Jul 21 1991 → …


All Science Journal Classification (ASJC) codes

  • Electronic, Optical and Magnetic Materials
  • Condensed Matter Physics
  • Computer Science Applications
  • Applied Mathematics
  • Electrical and Electronic Engineering

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