Patent ID: 8781967

Claim:
A method for embedding auxiliary information symbols in an encrypted host content, comprising: produce a first encrypted content by (a) obtaining a plurality of segments of an original host content, (b) embedding each of said plurality of segments with a first logical value and (c) using a first encryption key or first set of encryption keys for encrypting each of said plurality of segments after having been embedded with said first logical value; producing a second content that is not in encrypted format by (a) embedding a second logical value into said plurality of segments of said original host content and (b) modifying each particular segment that is embedded with said second logical value with a corresponding segment that is embedded with said first logical value, said corresponding segment being perceptually similar to said particular segment but for having said first logical value embedded therein instead of said second logical value; and combining a first set of segments from said first encrypted content with a second set of segments from said second content in a pre-defined manner, without decrypting said first encrypted content, to produce a composite encrypted host content with embedded auxiliary information, wherein said composite encrypted host content is decryptable using said first encryption key or said first set of encryption keys.