Patent ID: 6721422
Filing Date: 2004-04-13
Classification: H04N

Abstract:
Conditional access system for controlling the access of receivers (7) of end-users to a data content source (2) in an uplink system (1), said uplink system comprising a scrambler (4) for scrambling data content supplied from the data content source (2), an entitlement control message generator (6) for generating entitlement control messages (ecm) containing a control word (cw) and an entitlement identification and a transmitter for transmitting the scrambled data content and the entitlement control messages, in which a descrambler (8), and an entitlement control message decoder (9) are associated to the receiver (7), and in which if a match between the entitlement in the entitlement control message (ecm) and the entitlement of the end-user exists, the entitlement control message decoder (9) supplies a control word (cw) to the descrambler (8) for descrambling a part of the received scrambled content for which the receiver is entitled, characterized in that a separator (3) is provided, coupled to the data content source (2) for separating a part of the data content from said source into at least one object data stream (os1) representing a preselected video object of the data content part and a remaining data stream (rs) representing the data content part without the preselected video object, that the at least one object data stream is supplied to the input of the scrambler (4) and that a combiner (10) is connected to the output of the descrambler (8) for combining the descrambled object data (dos1, dos2) with the remaining data content (rs), in which an individual entitlement is allocated to said object.