5. The method of claim 1 , further comprising: establishing an imaging field of view; and defining a said region in said field of view; wherein: detecting said actor input comprises receiving at least one image of said field of view, with said actor input therein and in said region.
5. The method of claim 1 , further comprising: establishing an imaging field of view; and defining a said region in said field of view; wherein: detecting said actor input comprises receiving at least one image of said field of view, with said actor input therein and in said region. 10. The method of claim 5 , further comprising: identifying a plurality of structural geometric salient features of said actor from said region in said image.