1. A system comprising: means for constructing a results key at a first processing station; an image capture and processing device, means for making the results key available to the image capture and processing device at a location remote from the first processing station, the image capture and processing device being operable to capture an image presented to a field of view of the image capture and processing device; the image capture and processing device including self-contained means for analyzing the field of view image in cooperation with the results key, and for providing an output signal based on the results of said analysis.