6. The method of claim 5 , wherein: said region is smaller than said field of view, and is substantially fully within said field of view.
6. The method of claim 5 , wherein: said region is smaller than said field of view, and is substantially fully within said field of view. 7. The method of claim 6 , further comprising: establishing first and second imaging fields of view; defining said region in said first imaging field of view; defining said region in said second imaging field of view; executing said actor input in said region; receiving at least one first image of said first imaging field of view, said first image comprising at least a portion of said actor input therein; receiving at least one second image of said second imaging field of view, said second image comprising at least a portion of said actor input therein; and identifying at least one structural geometric salient feature of said actor from said actor input in said region in said first and second images.