Imagine a surveillance camera in a typical convenience store in the 1980s. That camera was big and expensive, and connected by a wire running through the wall to a VCR sitting in a back room. There have been significant advances in camera technology in the ensuing decades — in resolution, digitization, storage, and wireless transmission — and cameras have become cheaper and far more prevalent. Still, for all those advances, the social implications of being recorded have not changed: when we walk into a store, we generally expect that the presence of cameras won’t affect us. We expect that our movements will be recorded, and we might feel self-conscious if we notice a camera, especially if we’re doing anything that we feel might attract attention. But unless something dramatic occurs, we generally understand that the videos in which we appear are unlikely to be scrutinized or monitored. All that is about to change.

Today’s capture-and-store video systems are starting to be augmented with active monitoring technology known variously as “video analytics,” “intelligent video analytics,” or “video content analysis.” The goal of this technology is to allow computers not just to record but also to understand the objects and actions that a camera is capturing. This can be used to alert the authorities when something or someone deemed “suspicious” is detected, or to collect detailed information about video subjects for security or marketing purposes. Behind all the dumb video camera “eyes” that record us will increasingly lie ever-smarter “brains” that will be monitoring us. As we will see, technologists are working on teaching computers to do that monitoring in remarkable ways across a broad variety of dimensions.