Selectable output control
The term selectable output control (SOC) (in German as selectable output control ) is one of the Federal Communications Commission introduced (FCC) preamble about the possibility specifically targeted at the broadcast of media content via digital control signals from the transmitter signal outputs of a receiver to (de- )activate.
meaning
Such a technology is particularly important in connection with copy protection methods such as HDCP or DTCP, in that analog signal outputs can be switched off or the signal quality reduced and the copy protection available in parallel can be activated on digital image outputs. It is also conceivable that recording devices controlled via DTCP receive a control signal that prevents the recording of transmitted content.
transmission
SOC in and of itself is just an umbrella term. There is no general standard that defines the behavior of receiving devices (of any type) to control signals for copy protection. In general, most of the transmission paths currently in use (via DVB) do not have a standardized transmission of copy protection or SOC control signals. All technologies currently used are of a proprietary nature, such as the "Broadcast Flag" that Premiere uses in Germany to activate HDCP protection for the HDMI output on "Premiere HD" certified HDTV receivers when switching to "Premiere HD Film" and switch the component outputs down to SDTV picture quality.
Currently it is according to 18 FCC Rcd. 20885 in the USA it is forbidden to use SOC techniques to completely switch off signal outputs if this affects approved analog or digital interfaces.
A so-called 'broadcast flag' only has the effect that the HDCP copy protection is activated on digital video outputs and the signal quality of analog video outputs is scaled down to SDTV. Nevertheless, a broadcast flag also represents a subset of SOC techniques.