Review Article

A Survey of Visual Sensor Networks

Figure 3

Finding the polygons that contain people based on a projection of the person' silhouettes on the planar scene [22].
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(a) Two cameras observe a person from different positions. The cameras’ cones are swept around the person’s silhouette
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(b) Polygons obtained as the intersection of planar projections of cones in the case of two objects. Visual hull presents the largest volume in which an object can reside. The dark-colored polygons do not contain any objects