Error Estimation for Known Marker Position Retrieval by Ideal Pinhole Camera Direct Observation


Article Preview

For Motion Capture in Gait Analysis using Known Spherical Markers one simple direct approach is to compute the projection of the Marker Center using its projection in the Pixel Plane and based on it to find the location of the Marker on the line that connects the Marker Center Projection and the camera Focal Point. For various positions of the Marker in the workspace the exact image of the marker is computed using a genuine approach and compute back the approximation of the position based on the generated image. Various algorithms are taken in consideration and finally the results are assessed from the point of view of Gait Analysis and two directions for calculus improvement are identified.



Edited by:

Prof.univ. Adrian Olaru




C. R. Mirescu and G. Roșca, "Error Estimation for Known Marker Position Retrieval by Ideal Pinhole Camera Direct Observation", Applied Mechanics and Materials, Vol. 841, pp. 192-197, 2016

Online since:

June 2016




* - Corresponding Author

[1] S. Shaid, T. Tumer, and C. Guler, Marker detection and trajectory generation algorithms for a multicamera based gait analysis system, Mechatronics (11) 2001, pp.409-437.


[2] C. R. Mirescu, G. Roșca, Estimate of Color Depth Discretization Impact on the Accuracy of an Ideal Pinhole Camera, Applied Mechanics and Materials, Vol. 811, pp.217-221, Nov. 2015; doi: 10. 4028/www. scientific. net/AMM. 811. 217.


[3] F. J. Yu, X. Luan, D. L. Song, X. F. Li, H. H. Zhou, A Novel High Accuracy Sub-Pixel Corner Detection Algorithm for Camera Calibration, Applied Mechanics and Materials, Vols. 239-240, pp.713-716, (2013).


[4] Reinhard Klette, Concise Computer Vision. An Introduction into Theory and Algorithms, Springer-Verlag, London, (2014).

[5] Information on https: /en. wikipedia. org/wiki/35mm_format.

[6] Information on http: /www. bobatkins. com/photography/technical/digitaldof. html.

[7] R. Baker, Measuring Walking; A handbook of Clinical Gait Analysis, Mac Keith Press, (2013).

[8] Andrea Castelli, Gabriele Paolini, Andrea Cereatti, Ugo Della Croce, A 2D Markerless Gait Analysis Methodology: Validation on Healthy Subjects; Computational and Mathematical Methods in Medicine, Volume 2015 (2015).


Fetching data from Crossref.
This may take some time to load.