VFH produces a histogram that encodes the geometry of the object and its viewpoint.
For every pair of a point and the center of mass, a reference frame is constructed and the three angular variations are computed (a, q, f) and also d which represents distance between (point, center of mass)
Another statistical feature is computed between the central viewpoint direction and the normal estimated at each point.
The quality of VFH description depends on the quality of the surface normal estimation at each point.