Hi, after doing test over several weeks I'm at the point where I really start wondering how much difference acutally is between iPi (markerless in general?) and professional Systems like Vicons. Are there really numbers or tests that show how much better those systems are compared to markerless MoCap? I mean except the frames rates... just 60fps ipi vs 60 fps Vicon?

Hello, this question is worth full-scale scientific research. Answer is not straightforward and depends on how you measure the difference.
Overall accuracy of iPi is comparable with accuracy of expensive systems. The main drawback is that solution is not real-time, and more time needed for processing.

The most relevant can be this article comparing iPi Dual-Kinect system with XSens system:

Streit P., Monat A., Guimarães C., Zamberlan M., Ribeiro F., Oliveira J.
Comparison and Evaluation of Kinematic Parameters of MOCAP Systems
Proceedings of Digital Human Modeling Symposium 2013.

http://ipisoft.com/pr/papers/Priscilla_ ... hm2013.pdf

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