Despite such qualms, computer vision is moving into the mainstream. With this technological evolution, scientists predict, people will increasingly be surrounded by machines that can not only see but also reason about what they are seeing, in their own limited way…

The future of law enforcement, national security and military operations will most likely rely on observant machines. A few months ago, the Defense Advanced Research Projects Agency, the Pentagon’s research arm, awarded the first round of grants in a five-year research program called the Mind’s Eye. Its goal is to develop machines that can recognize, analyze and communicate what they see. Mounted on small robots or drones, these smart machines could replace human scouts. “These things, in a sense, could be team members,” said James Donlon, the program’s manager.

Millions of people now use products that show the progress that has been made in computer vision. In the last two years, the major online photo-sharing services — Picasa by Google, Windows Live Photo Gallery by Microsoft, Flickr by Yahoo and iPhoto by Apple — have all started using face recognition. A user puts a name to a face, and the service finds matches in other photographs. It is a popular tool for finding and organizing pictures.