Method and device to embed watermark in uncompressed video data

A client device comprising:

• an interface configured to receive an encrypted message comprising a watermark instruction, a content key, and a signature;
• a descrambler having an input to receive an encrypted compressed content and an output to produce a decrypted compressed content based on the content key;
• a decoder configured to convert the decrypted compressed content into uncompressed content;
• a watermark inserter connected to the output of the decoder, the watermark inserter being configured to switch between enabling and disabling the insertion of a watermark into the uncompressed content based on the watermark instruction;
• a secure activation module connected to the watermark inserter;
• a secure element connected to the interface, the descrambler and the secure activation module;
• wherein the interface is configured to verify the signature of the encrypted message and, in response to the verification of the signature, to transfer the watermark instruction to the secure activation module via the secure element;
• wherein said secure element is configured to verify that the watermark instruction was successfully transferred to the watermark inserter and, in response to the verification of the successful transfer of the watermark instruction to the watermark inserter, to transfer the content key to the descrambler;
• and
• wherein the secure activation module comprises a random number generator configured to produce a random number, said secure activation module generating, storing and sending said random number to the secure element, the secure element being configured to prepare a message containing at least the watermark instruction, the random number, and a second signature on both the watermark instruction and the random number, said secure activation module being configured to verify that the signature is authentic and that the random number is the same as the stored random number and, in response to the verification that the signature is authentic and that the random number is the same as the stored random number, accept the watermark instruction and send a final acknowledgment message to the secure element in order to inform the secure element of the successful completion of the transfer.