Patent ID: 9729941
Date: 2017-08-08
CPC Classifications: G06F,H04N

Claim:
1. A method to watermark a content received by a client device, the method comprising: receiving an encrypted compressed content at the client device, the encrypted compressed content being encrypted by at least one content key; receiving the encrypted compressed content at an input of a descrambler of the client device, and producing a decrypted compressed content at an output of the descrambler; receiving an entitlement control message (ECM) and pre-marking data at the client device, the ECM including the at least one content key, the ECM being encrypted by a first transmission key, the pre-marking data being encrypted; decrypting the ECM with the first transmission key and extracting the content key; decrypting the pre-marking data; verifying a signature of the pre-marking data by a conditioner of the client device, and in response to the verification of the signature, transferring the pre-marking data and an identifier contained in the conditioner to a watermark (WM) inserter of the client device; validating the content key for the descrambler; and watermarking, by the WM inserter, the decrypted compressed content received directly from the descrambler using the pre-marking data and the identifier.