A digital broadcast station is configured to "turn around" and add interactive programming to a television signal conveyed by a remote network. Prior to conveying the television signal, the remote network inserts a trigger within the vertical blanking interval of the signal. The trigger contains command information to control the loading and/or playing of a designated interactive program. After the trigger is combined with the television signal, the combined signal is modulated and transmitted from the remote network via a satellite uplink. This combined signal is correspondingly received at the digital broadcast station where it is digitized and routed through a video network for channel assignment and other processing. From the video network, the digitized television signal is provided to a VBI decoder which extracts the trigger. The extracted trigger is provided to an interactive flow manager and server to control the loading or playing of an interactive program identified by the trigger. The remainder of the digitized television signal is provided to a video encoder where it is compressed. An AVI generation unit of the digital broadcast station then combines the compressed television signal and the interactive program to form an AVI signal to be broadcast to end users via a satellite uplink.

For possible use in an electronic content distribution system, automatic recognition of compact discs or other storage media containing particular content, and corresponding account crediting is described. In an electronic content distribution system, such as those providing music available by digital downloading or streaming technologies, a user may ordinarily pay a full price to receive the music. A user who possesses and apparently owns a compact disc containing particular content can be conveniently offered a discount or credit usable towards the purchase of the analogous particular content in a form provided by the electronic content distribution system. Preferably, compact discs are uniquely identified by determining whether their digital fingerprint matches a known reference fingerprint for a compact disc containing the particular content.

An apparatus and method for transferring from a broadcaster to a receiver a limited reproduction right in data. A signal indicating the limited reproduction right is transmitted by the broadcaster and stored by the receiver with the data. The receiver reproduces and processes the data as a function of this signal.

A multiplex broadcasting method and system which limits an object district for broadcasting of district information such as a commercial message relating closely to the district is disclosed. On the broadcasting station side, multiplex data such as animation are broadcast with a district code such as a postal code number added thereto. On the receiving set side, a district code of the location is registered as an identification number of the multiplex broadcast receiving set in a memory in advance, and the district code of received multiplex data separated by a data extraction circuit and the identification number stored in the memory are compared with each other. Only when they coincide with each other, an image corresponding to the received multiplex data is displayed on the receiving set.

A digital conditional access module for a subscriber terminal comprises a decryption device including at least one PID register and an associated countdown register. The decryption device is enabled for decrypting received product packets having a PID matching a PID stored in the PID register so long as the associated countdown register is characterized by a non-zero value. Decryption of a product packet results in the countdown register being decremented by a selected factor, the countdown register being prevented from assuming a zero value by setting its contents to a selected value in response to a received conditional access packet containing a PID matching the PID stored in the PID register. The selected value to which the countdown register is set may also be contained within the received conditional access packet.