People get cameras stolen all the time. Today’s invention is a security feature which attempts to make them useless to thieves.
Each digital camera would require that the first picture taken after switch-on was of the owner’s face. It’s relatively easy to make existing on-board face recognition work well when required to know one face reliably. (It might be possible to require snapping something else known only to the owner, such as a particular watch face or a page in a passport).
If the first picture is something else, then the camera would automatically shut down -making the theft of cameras pointless.