Methods, devices and system for generating a watermarked stream

A server (60) for providing conditional access streams (30) and encrypted control messages (20), subsequently usable as input data for generating a watermarked stream (39) embedding a watermarking information (38), comprising:

• a watermarking information generator (64) configured to provide said watermarking information (38);
• a stream generator (63) configured to provide said conditional access streams (30) including a main stream (33) and watermarking data streams (35);
• a scrambler (65) configured to apply a protection on at least some of said conditional access streams (30);
• a message generator (62) configured to provide said control messages (20) with access data (AC, AR) suitable to enforce a selective processing of said watermarking data streams (35);
• a control unit (68) configured to correlate, through said control messages (20), said selective processing with said watermarking information (38), in order to allow subsequent embedding of said watermarking information (38) in the watermarked stream (39);
• and
• an output interface (69) configured to output, from the server (60), said control messages (20) and said conditional access streams (30).

A method for generating a watermarked stream (39) in a device (40) suitable to receive encrypted control messages (20) and conditional access streams (30), said conditional access streams (30) including a main stream (33) and watermarking data streams (35) from which a watermarking information (38) can be embedded in the watermarked stream (39);

• said method comprising:
• processing, in a security module (43) of the device (40), at least some of said control messages (20) for retrieving access data (AC, AR) therefrom,
• removing protection applied on at least some of said conditional access streams (30);
• selectively processing said watermarking data streams (35) depending on said access data (AC, AR), in order to generate the watermarked stream (39) from said conditional access streams (30).

A method for providing conditional access streams (30) and encrypted control messages (20), subsequently usable as input data for generating a watermarked stream (39) embedding a watermarking information (38), comprising:

• providing said watermarking information (38);
• providing said main stream (33) and said watermarking data streams (35);
• protecting at least some of said conditional access streams (30);
• providing said control messages (20) with access data (AC, AR) suitable to enforce a selective processing of said watermarking data streams (35);
• correlating, through said control messages (20), said selective processing with said watermarking information (38), in order to allow subsequent embedding of said watermarking information (38) in the watermarked stream (39);
• and
• outputting said control messages (20) and said conditional access streams (30), so as to allow subsequent generation of said watermarked stream (39) therefrom.