Patent ID: 7702101

Claim:
A method, comprising: importing, by a processor, a media stream having an encrypted portion; decrypting said encrypted portion; encoding said media stream into digital content, wherein said encoding comprises: encrypting a portion of that digital content, less than the entire digital content, the portion of the digital content that is encrypted being required for presentation of the media stream, said encrypting comprising: encrypting at least some audio or video data using a block-substitution cipher; not encrypting at least some audio or video data using that block-substitution cipher; identifying a first set of data and a second set of data in the digital content; and encrypting the first set of data and the second set of data, such that the first set of data can be made available to a first set of users and the second set of data can be made available to a second set of users, the first set of users being distinguishable from the second set of users; and not encrypting a portion of that digital content, less than the entire digital content, the portion of the digital content that is not encrypted being necessary for conducting navigation operations on, without decrypting, the media stream represented by the digital content.