Direct Estimation of the Backward Flow

Javier Sánchez, Agustin Salgado, Nelson Monzón

Abstract

The aim of this work is to propose a new method for estimating the backward flow directly from the optical flow. We assume that the optical flow has already been computed and we need to estimate the inverse mapping. This mapping is not bijective due to the presence of occlusions and disocclusions, therefore it is not possible to estimate the inverse function in the whole domain. Values in these regions has to be guessed from the available information. We propose an accurate algorithm to calculate the backward flow uniquely from the optical flow, using a simple relation. Occlusions are filled by selecting the maximum motion and disocclusions are filled with two different strategies: a min-fill strategy, which fills each disoccluded region with the minimum value around the region; and a restricted min-fill approach that selects the minimum value in a close neighborhood. In the experimental results, we show the accuracy of the method and compare the results using these two strategies.

References

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Paper Citation


in Harvard Style

Sánchez J., Salgado A. and Monzón N. (2013). Direct Estimation of the Backward Flow . In Proceedings of the International Conference on Computer Vision Theory and Applications - Volume 2: VISAPP, (VISIGRAPP 2013) ISBN 978-989-8565-48-8, pages 268-273. DOI: 10.5220/0004284902680273


in Bibtex Style

@conference{visapp13,
author={Javier Sánchez and Agustin Salgado and Nelson Monzón},
title={Direct Estimation of the Backward Flow},
booktitle={Proceedings of the International Conference on Computer Vision Theory and Applications - Volume 2: VISAPP, (VISIGRAPP 2013)},
year={2013},
pages={268-273},
publisher={SciTePress},
organization={INSTICC},
doi={10.5220/0004284902680273},
isbn={978-989-8565-48-8},
}


in EndNote Style

TY - CONF
JO - Proceedings of the International Conference on Computer Vision Theory and Applications - Volume 2: VISAPP, (VISIGRAPP 2013)
TI - Direct Estimation of the Backward Flow
SN - 978-989-8565-48-8
AU - Sánchez J.
AU - Salgado A.
AU - Monzón N.
PY - 2013
SP - 268
EP - 273
DO - 10.5220/0004284902680273