| 摘要 |
Methods, apparatus and systems for embedding auxiliary information in encrypted host signals are provided. The present invention enables secure application of digital watermarks at any point in the transmission and/or distribution of digital content by enabling the insertion of a plurality of digital watermarks, without the knowledge of the encryption/decryption keys, into a digital host content that has been encrypted with an encryption key. The embedded watermarks persist throughout the content subsequent to the decryption of the content. The disclosed techniques are applicable to content that has been encrypted using a variety of different encryption techniques and algorithms, including stream ciphers, block ciphers, symmetric and asymmetric encryption algorithms. These methods are further adapted to enable the insertion of watermarks into a content that is compressed prior to encryption. |
