The present disclosure provides methods and systems for processing data. One claim recites a method practiced using used a user's camera-equipped portable computer system. The method includes the acts of: capturing image data corresponding to a region using the camera of the portable computer system; applying a filter to the captured image data, in which the filter prioritizes image data at a center of the region and averages images data at a relative distance from the center region; and searching the filtered image data for hidden keys. Of course, other combinations and claims are provided as well.