Augmented reality smart television (AR-STV) provides an AR-based TV broadcasting service to implement the mixed content of a broadcasting programme and augmented content at a targeted position (augmentation region) and time (augmentation time) in real-time on a receiving terminal such as a smart TV or set-top-box (STB). AR-STV overlays augmented contents provided by the broadcasting provider itself or by the content providers which are authorised by the broadcasting provider. When AR-STV is provided@ the broadcasting signal includes the metadata which contains the permissions about timing and the area for the overlay. Authorisation information for an AR content provider is also provided in the broadcasting signal. This mechanism does not permit any illegal overlay. The AR-STV is realized by the combination of a specific signal on the broadcasting programme@ metadata@ augmented content and terminal side synchronization. The terminal functionality can be implemented as the extension of the existing integrated broadcast-broadband (IBB) systems. The scope of this Recommendation comprises the following technologies to realize AR-STV: ?C Synchronization scheme for AR-STV ?CMetadata for AR-STV ?C Signalling protocol for AR-STV This Recommendation specifies three technologies for AR-STV@ (1) synchronized representation between a broadcasting programme and augmented content@ (2) metadata and (3) signalling protocol according to functional requirements defined in [ITU-T J.301].