Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A Framework for Real-Time Face and Facial Feature Tracking using Optical
  Flow Pre-estimation and Template Tracking   This work presents a framework for tracking head movements and capturing the
movements of the mouth and both the eyebrows in real-time. We present a head
tracker which is a combination of a optical flow and a template based tracker.
The estimation of the optical flow head tracker is used as starting point for
the template tracker which fine-tunes the head estimation. This approach
together with re-updating the optical flow points prevents the head tracker
from drifting. This combination together with our switching scheme, makes our
tracker very robust against fast movement and motion-blur. We also propose a
way to reduce the influence of partial occlusion of the head. In both the
optical flow and the template based tracker we identify and exclude occluded
points.

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The categories of this paper are: math
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The categories of this paper are: physics
14
The categories of this paper are: math-ph
24
The categories of this paper are: dg-ga
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The categories of this paper are: hep-lat
13
The categories of this paper are: quant-ph
25
The categories of this paper are: patt-sol
37
The categories of this paper are: supr-con
36
The categories of this paper are: cmp-lg
23
The categories of this paper are: solv-int
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The categories of this paper are: cond-mat
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The categories of this paper are: astro-ph
8
The categories of this paper are: hep-ex
20
The categories of this paper are: acc-phys
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The categories of this paper are: econ
5
The categories of this paper are: gr-qc