VideoTrack 3D

Motion capture by fitting a kinematic body model

VideoTrack 3D is a new optical motion capture approach that is suitable for a wide range of studies in neuroethology and motor control. Based on the stochastic search algorithm of Simulated Annealing, it utilizes a kinematic body model that includes joint angle constraints to reconstruct posture from an arbitrary number of views.

Rather than tracking marker trajectories in time, the algorithm minimizes an error function that compares predicted model projections to the recorded views. Thus, each video-frame is analysed independently from other frames, enabling the system to recover from incorrectly analysed postures. The system works with standard computer and video equipment.
Schematic view of 2 views of one scene and model fitting
3D-movement reconstruction is possible even from a single view. This is reached in spite of marker fusions and occlusions, simply by exploiting the natural contraints imposed by a kinematic chain and a known experimental setup.

Screenshot of 3D Videotrack

Full publication:
Zakotnik J, Matheson T, Dürr V (2004)
A posture optimization algorithm for model-based motion capture of movement sequences
Journal of Neuroscience Methods, Vol 135/1-2, pp 43-54 (.pdf)