# NEW CLOSED FORM SOLUTIONS FOR SKELETAL EXTRACTION FROM MOTION CAPTURE

### Sudhanshhu Semwal, Jonathan Kip Knight

#### Abstract

We present a fast closed form solution for estimating the exact joint locations inside the human body from motion capture data. The new closed-form solution is more robust and faster. For example, the formulae are as much as about 100 times faster than the traditional non-linear Maximum Likelihood Estimator and about 9 times faster than linear least squares methods. The methods are proven to be statistically efficient when measurement error is smaller than the joint-marker distance. Unbiased Generalized Delogne-Kása (UGDK), multiple radii solution, and incremental GDK are important contributions of our research providing closed form fast solutions for skeleton extraction from motion capture data. Skeletal animation sequences are generated using the CMU and Eric Camper’s motion capture database.

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#### Paper Citation

#### in Harvard Style

Semwal S. and Knight J. (2009). **NEW CLOSED FORM SOLUTIONS FOR SKELETAL EXTRACTION FROM MOTION CAPTURE** . In *Proceedings of the Fourth International Conference on Computer Graphics Theory and Applications - Volume 1: GRAPP, (VISIGRAPP 2009)* ISBN 978-989-8111-67-8, pages 249-256. DOI: 10.5220/0001799702490256

#### in Bibtex Style

@conference{grapp09,

author={Sudhanshhu Semwal and Jonathan Kip Knight},

title={NEW CLOSED FORM SOLUTIONS FOR SKELETAL EXTRACTION FROM MOTION CAPTURE},

booktitle={Proceedings of the Fourth International Conference on Computer Graphics Theory and Applications - Volume 1: GRAPP, (VISIGRAPP 2009)},

year={2009},

pages={249-256},

publisher={SciTePress},

organization={INSTICC},

doi={10.5220/0001799702490256},

isbn={978-989-8111-67-8},

}

#### in EndNote Style

TY - CONF

JO - Proceedings of the Fourth International Conference on Computer Graphics Theory and Applications - Volume 1: GRAPP, (VISIGRAPP 2009)

TI - NEW CLOSED FORM SOLUTIONS FOR SKELETAL EXTRACTION FROM MOTION CAPTURE

SN - 978-989-8111-67-8

AU - Semwal S.

AU - Knight J.

PY - 2009

SP - 249

EP - 256

DO - 10.5220/0001799702490256