1. One or more computer storage memory having stored thereon multiple instructions that, when executed by one or more processors, cause the one or more processors to: receive a global tag for an image, the global tag identifying one or more objects in the image; receive a region-specific tag for the image, the region-specific tag identifying one or more objects in a region of the image and having an association with the region of the image, the region-specific tag including a first label of a person in the region that is used by a first user to identify the person in the region; store the global tag and the region-specific tag with the image; determine a second label of the person in the region that is used by a second user to identify the person in the region; display, along with the image, an identifier for each of the one or more objects identified in the global tag, and an identifier for each of the one or more objects identified in the region-specific tag; display, when displaying the image for the first user, the first label for the person in the region; display, when displaying the image for the second user, the second label for the person in the region; and enable conversion of the global tag to an additional region-specific tag, and enable conversion of the region-specific tag to an additional global tag that is associated with the image as a whole, the conversion of the region-specific tag to the additional global tab comprising removal of the association with the region of the image from the region-specific tag to cause the region-specific tag to become the additional global tag that is associated with the image as a whole.