These markers may include QR codes, images, serial numbers, or any other object that is isolated from its environment for the camera to see.
Ihe ngosi a nwere ike ịbụ QR codes , nọmba serial, ma ọ bụ ihe ọ bụla ọzọ nwere ike ịpụ iche na gburugburu ya maka igwefoto ịhụ.