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arXiv · 1904.11592

Optical Flow Techniques for Facial Expression Analysis -- a Practical Evaluation Study

Benjamin Allaert·Isaac Ronald Ward·Ioan Marius Bilasco·Chaabane Djeraba·Mohammed Bennamoun
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Abstract

Optical flow techniques are becoming increasingly performant and robust when estimating motion in a scene, but their performance has yet to be proven in the area of facial expression recognition. In this work, a variety of optical flow approaches are evaluated across multiple facial expression datasets, so as to provide a consistent performance evaluation. The aim of this work is not to propose a new expression recognition technique, but to understand better the adequacy of existing state-of-the art optical flow for encoding facial motion in the context of facial expression recognition. Our evaluations highlight the fact that motion approximation methods used to overcome motion discontinuities have a significant impact when optical flows are used to characterize facial expressions.

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Benjamin Allaert, Isaac Ronald Ward, Ioan Marius Bilasco, Chaabane Djeraba, Mohammed Bennamoun. 2019-04-25. Optical Flow Techniques for Facial Expression Analysis -- a Practical Evaluation Study. https://doi.org/10.1016/j.neucom.2022.05.077

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